Java tutorial
/* * Author: alessandro crugnola * alessandro.crugnola@gmail.com * * Fork based on the google opensource framework * * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.zhongsou.souyue.ui; import android.annotation.TargetApi; import android.content.Context; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.PixelFormat; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.support.v4.util.SparseArrayCompat; import android.util.AttributeSet; import android.util.Log; import android.view.FocusFinder; import android.view.KeyEvent; import android.view.SoundEffectConstants; import android.view.View; import android.view.ViewDebug; import android.view.ViewGroup; import android.view.ViewParent; import android.view.accessibility.AccessibilityEvent; import android.view.accessibility.AccessibilityNodeInfo; import android.widget.ArrayAdapter; import android.widget.Checkable; import android.widget.ListAdapter; import android.widget.ListView; import android.widget.RemoteViews.RemoteView; import android.widget.WrapperListAdapter; import com.zhongsou.souyue.R; import java.util.ArrayList; /* * Implementation Notes: * * Some terminology: * * index - index of the items that are currently visible * position - index of the items in the cursor */ /** * A view that shows items in a vertically scrolling list. The items come from the {@link ListAdapter} associated with this view. * <p/> * <p> * See the <a href="{@docRoot}guide/topics/ui/layout/listview.html">List View</a> guide. * </p> * * @attr ref android.R.styleable#ListView_entries * @attr ref android.R.styleable#ListView_divider * @attr ref android.R.styleable#ListView_dividerHeight * @attr ref android.R.styleable#ListView_headerDividersEnabled * @attr ref android.R.styleable#ListView_footerDividersEnabled */ @RemoteView public class HListView extends AbsHListView { /** * Used to indicate a no preference for a position type. */ static final int NO_POSITION = -1; /** * When arrow scrolling, ListView will never scroll more than this factor times the height of the list. */ private static final float MAX_SCROLL_FACTOR = 0.33f; /** * When arrow scrolling, need a certain amount of pixels to preview next items. This is usually the fading edge, but if that is * small enough, we want to make sure we preview at least this many pixels. */ private static final int MIN_SCROLL_PREVIEW_PIXELS = 2; private static final String LOG_TAG = "HListView"; /** * A class that represents a fixed view in a list, for example a header at the top or a footer at the bottom. */ public static class FixedViewInfo { /** * The view to add to the list */ public View view; /** * The data backing the view. This is returned from {@link ListAdapter#getItem(int)}. */ public Object data; /** * <code>true</code> if the fixed view should be selectable in the list */ public boolean isSelectable; } private ArrayList<FixedViewInfo> mHeaderViewInfos = new ArrayList<HListView.FixedViewInfo>(); private ArrayList<FixedViewInfo> mFooterViewInfos = new ArrayList<HListView.FixedViewInfo>(); Drawable mDivider; int mDividerWidth; int mMeasureWithChild; Drawable mOverScrollHeader; Drawable mOverScrollFooter; private boolean mIsCacheColorOpaque; private boolean mDividerIsOpaque; private boolean mHeaderDividersEnabled; private boolean mFooterDividersEnabled; private boolean mAreAllItemsSelectable = true; private boolean mItemsCanFocus = false; // used for temporary calculations. private final Rect mTempRect = new Rect(); private Paint mDividerPaint; // the single allocated result per list view; kinda cheesey but avoids // allocating these thingies too often. private final ArrowScrollFocusResult mArrowScrollFocusResult = new ArrowScrollFocusResult(); // Keeps focused children visible through resizes private FocusSelector mFocusSelector; public HListView(Context context) { this(context, null); } public HListView(Context context, AttributeSet attrs) { this(context, attrs, R.attr.hlv_listViewStyle); } public HListView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); if (LOG_ENABLED) { Log.i(LOG_TAG, "defStyle: " + defStyle); } final Resources.Theme theme = context.getTheme(); TypedArray array = theme.obtainStyledAttributes(attrs, R.styleable.HListView, defStyle, 0); CharSequence[] entries = null; Drawable dividerDrawable = null; Drawable overscrollHeader = null; Drawable overscrollFooter = null; int dividerWidth = 0; boolean headerDividersEnabled = true; boolean footerDividersEnabled = true; int measureWithChild = -1; if (null != array) { entries = array.getTextArray(R.styleable.HListView_android_entries); dividerDrawable = array.getDrawable(R.styleable.HListView_android_divider); overscrollHeader = array.getDrawable(R.styleable.HListView_hlv_overScrollHeader); overscrollFooter = array.getDrawable(R.styleable.HListView_hlv_overScrollFooter); dividerWidth = array.getDimensionPixelSize(R.styleable.HListView_hlv_dividerWidth, 0); headerDividersEnabled = array.getBoolean(R.styleable.HListView_hlv_headerDividersEnabled, true); footerDividersEnabled = array.getBoolean(R.styleable.HListView_hlv_footerDividersEnabled, true); measureWithChild = array.getInteger(R.styleable.HListView_hlv_measureWithChild, -1); array.recycle(); if (LOG_ENABLED) { Log.d(LOG_TAG, "divider: " + dividerDrawable); Log.d(LOG_TAG, "overscrollHeader: " + overscrollHeader); Log.d(LOG_TAG, "overscrollFooter: " + overscrollFooter); Log.d(LOG_TAG, "dividerWith: " + dividerWidth); Log.d(LOG_TAG, "headerDividersEnabled: " + headerDividersEnabled); Log.d(LOG_TAG, "footerDividersEnabled: " + footerDividersEnabled); Log.d(LOG_TAG, "measureWithChild: " + measureWithChild); } } if (entries != null) { setAdapter(new ArrayAdapter<CharSequence>(context, android.R.layout.simple_list_item_1, entries)); } if (dividerDrawable != null) { // If a divider is specified use its intrinsic height for divider height setDivider(dividerDrawable); } if (overscrollHeader != null) { setOverscrollHeader(overscrollHeader); } if (overscrollFooter != null) { setOverscrollFooter(overscrollFooter); } // Use the height specified, zero being the default if (dividerWidth != 0) { setDividerWidth(dividerWidth); } mHeaderDividersEnabled = headerDividersEnabled; mFooterDividersEnabled = footerDividersEnabled; mMeasureWithChild = measureWithChild; } /** * @return The maximum amount a list view will scroll in response to an arrow event. */ public int getMaxScrollAmount() { return (int) (MAX_SCROLL_FACTOR * (getRight() - getLeft())); } /** * Make sure views are touching the top or bottom edge, as appropriate for our gravity */ private void adjustViewsLeftOrRight() { final int childCount = getChildCount(); int delta; if (childCount > 0) { View child; if (!mStackFromRight) { // Uh-oh -- we came up short. Slide all views up to make them // align with the top child = getChildAt(0); delta = child.getLeft() - mListPadding.left; if (mFirstPosition != 0) { // It's OK to have some space above the first item if it is // part of the vertical spacing delta -= mDividerWidth; } if (delta < 0) { // We only are looking to see if we are too low, not too high delta = 0; } } else { // we are too high, slide all views down to align with bottom child = getChildAt(childCount - 1); delta = child.getRight() - (getWidth() - mListPadding.right); if (mFirstPosition + childCount < mItemCount) { // It's OK to have some space below the last item if it is // part of the vertical spacing delta += mDividerWidth; } if (delta > 0) { delta = 0; } } if (delta != 0) { offsetChildrenLeftAndRight(-delta); } } } /** * Add a fixed view to appear at the top of the list. If addHeaderView is called more than once, the views will appear in the * order they were added. Views added using this call can take focus if they want. * <p/> * NOTE: Call this before calling setAdapter. This is so ListView can wrap the supplied cursor with one that will also account * for header and footer views. * * @param v The view to add. * @param data Data to associate with this view * @param isSelectable whether the item is selectable */ public void addHeaderView(View v, Object data, boolean isSelectable) { if (mAdapter != null && !(mAdapter instanceof HeaderViewListAdapter)) { throw new IllegalStateException( "Cannot add header view to list -- setAdapter has already been called."); } FixedViewInfo info = new FixedViewInfo(); info.view = v; info.data = data; info.isSelectable = isSelectable; mHeaderViewInfos.add(info); // in the case of re-adding a header view, or adding one later on, // we need to notify the observer if (mAdapter != null && mDataSetObserver != null) { mDataSetObserver.onChanged(); } } /** * Add a fixed view to appear at the top of the list. If addHeaderView is called more than once, the views will appear in the * order they were added. Views added using this call can take focus if they want. * <p/> * NOTE: Call this before calling setAdapter. This is so ListView can wrap the supplied cursor with one that will also account * for header and footer views. * * @param v The view to add. */ public void addHeaderView(View v) { addHeaderView(v, null, true); } @Override public int getHeaderViewsCount() { return mHeaderViewInfos.size(); } /** * Removes a previously-added header view. * * @param v The view to remove * @return true if the view was removed, false if the view was not a header view */ public boolean removeHeaderView(View v) { if (mHeaderViewInfos.size() > 0) { boolean result = false; if (mAdapter != null && ((HeaderViewListAdapter) mAdapter).removeHeader(v)) { if (mDataSetObserver != null) { mDataSetObserver.onChanged(); } result = true; } removeFixedViewInfo(v, mHeaderViewInfos); return result; } return false; } private void removeFixedViewInfo(View v, ArrayList<FixedViewInfo> where) { int len = where.size(); for (int i = 0; i < len; ++i) { FixedViewInfo info = where.get(i); if (info.view == v) { where.remove(i); break; } } } /** * Add a fixed view to appear at the bottom of the list. If addFooterView is called more than once, the views will appear in the * order they were added. Views added using this call can take focus if they want. * <p/> * NOTE: Call this before calling setAdapter. This is so ListView can wrap the supplied cursor with one that will also account * for header and footer views. * * @param v The view to add. * @param data Data to associate with this view * @param isSelectable true if the footer view can be selected */ public void addFooterView(View v, Object data, boolean isSelectable) { // NOTE: do not enforce the adapter being null here, since unlike in // addHeaderView, it was never enforced here, and so existing apps are // relying on being able to add a footer and then calling setAdapter to // force creation of the HeaderViewListAdapter wrapper FixedViewInfo info = new FixedViewInfo(); info.view = v; info.data = data; info.isSelectable = isSelectable; mFooterViewInfos.add(info); // in the case of re-adding a footer view, or adding one later on, // we need to notify the observer if (mAdapter != null && mDataSetObserver != null) { mDataSetObserver.onChanged(); } } /** * Add a fixed view to appear at the bottom of the list. If addFooterView is called more than once, the views will appear in the * order they were added. Views added using this call can take focus if they want. * <p/> * NOTE: Call this before calling setAdapter. This is so ListView can wrap the supplied cursor with one that will also account * for header and footer views. * * @param v The view to add. */ public void addFooterView(View v) { addFooterView(v, null, true); } @Override public int getFooterViewsCount() { return mFooterViewInfos.size(); } /** * Removes a previously-added footer view. * * @param v The view to remove * @return true if the view was removed, false if the view was not a footer view */ public boolean removeFooterView(View v) { if (mFooterViewInfos.size() > 0) { boolean result = false; if (mAdapter != null && ((HeaderViewListAdapter) mAdapter).removeFooter(v)) { if (mDataSetObserver != null) { mDataSetObserver.onChanged(); } result = true; } removeFixedViewInfo(v, mFooterViewInfos); return result; } return false; } /** * Returns the adapter currently in use in this ListView. The returned adapter might not be the same adapter passed to * {@link #setAdapter(ListAdapter)} but might be a {@link WrapperListAdapter}. * * @return The adapter currently used to display data in this ListView. * @see #setAdapter(ListAdapter) */ @Override public ListAdapter getAdapter() { return mAdapter; } /** * Sets the data behind this ListView. * <p/> * The adapter passed to this method may be wrapped by a {@link WrapperListAdapter}, depending on the ListView features currently * in use. For instance, adding headers and/or footers will cause the adapter to be wrapped. * * @param adapter The ListAdapter which is responsible for maintaining the data backing this list and for producing a view to * represent an item in that data set. * @see #getAdapter() */ @Override public void setAdapter(ListAdapter adapter) { if (mAdapter != null && mDataSetObserver != null) { mAdapter.unregisterDataSetObserver(mDataSetObserver); } resetList(); mRecycler.clear(); if (mHeaderViewInfos.size() > 0 || mFooterViewInfos.size() > 0) { mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, adapter); } else { mAdapter = adapter; } mOldSelectedPosition = INVALID_POSITION; mOldSelectedColId = INVALID_COL_ID; // AbsListView#setAdapter will update choice mode states. super.setAdapter(adapter); if (mAdapter != null) { mAreAllItemsSelectable = mAdapter.areAllItemsEnabled(); mOldItemCount = mItemCount; mItemCount = mAdapter.getCount(); checkFocus(); mDataSetObserver = new AdapterDataSetObserver(); mAdapter.registerDataSetObserver(mDataSetObserver); mRecycler.setViewTypeCount(mAdapter.getViewTypeCount()); int position; if (mStackFromRight) { position = lookForSelectablePosition(mItemCount - 1, false); } else { position = lookForSelectablePosition(0, true); } setSelectedPositionInt(position); setNextSelectedPositionInt(position); if (mItemCount == 0) { // Nothing selected checkSelectionChanged(); } } else { mAreAllItemsSelectable = true; checkFocus(); // Nothing selected checkSelectionChanged(); } requestLayout(); } /** * The list is empty. Clear everything out. */ @Override protected void resetList() { // The parent's resetList() will remove all views from the layout so we need to // cleanup the state of our footers and headers clearRecycledState(mHeaderViewInfos); clearRecycledState(mFooterViewInfos); super.resetList(); mLayoutMode = LAYOUT_NORMAL; } private void clearRecycledState(ArrayList<FixedViewInfo> infos) { if (infos != null) { final int count = infos.size(); for (int i = 0; i < count; i++) { final View child = infos.get(i).view; final LayoutParams p = (LayoutParams) child.getLayoutParams(); if (p != null) { p.recycledHeaderFooter = false; } } } } /** * @return Whether the list needs to show the top fading edge */ private boolean showingLeftFadingEdge() { final int listLeft = getScrollX() + mListPadding.left; return (mFirstPosition > 0) || (getChildAt(0).getLeft() > listLeft); } /** * @return Whether the list needs to show the bottom fading edge */ private boolean showingRightFadingEdge() { final int childCount = getChildCount(); final int rightOfRightChild = getChildAt(childCount - 1).getRight(); final int lastVisiblePosition = mFirstPosition + childCount - 1; final int listRight = getScrollX() + getWidth() - mListPadding.right; return (lastVisiblePosition < mItemCount - 1) || (rightOfRightChild < listRight); } @Override public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate) { int rectLeftWithinChild = rect.left; // offset so rect is in coordinates of the this view rect.offset(child.getLeft(), child.getTop()); rect.offset(-child.getScrollX(), -child.getScrollY()); final int width = getWidth(); int listUnfadedLeft = getScrollX(); int listUnfadedRight = listUnfadedLeft + width; final int fadingEdge = getHorizontalFadingEdgeLength(); if (showingLeftFadingEdge()) { // leave room for top fading edge as long as rect isn't at very top if ((mSelectedPosition > 0) || (rectLeftWithinChild > fadingEdge)) { listUnfadedLeft += fadingEdge; } } int childCount = getChildCount(); int rightOfRightChild = getChildAt(childCount - 1).getRight(); if (showingRightFadingEdge()) { // leave room for bottom fading edge as long as rect isn't at very bottom if ((mSelectedPosition < mItemCount - 1) || (rect.right < (rightOfRightChild - fadingEdge))) { listUnfadedRight -= fadingEdge; } } int scrollXDelta = 0; if (rect.right > listUnfadedRight && rect.left > listUnfadedLeft) { // need to MOVE DOWN to get it in view: move down just enough so // that the entire rectangle is in view (or at least the first // screen size chunk). if (rect.width() > width) { // just enough to get screen size chunk on scrollXDelta += (rect.left - listUnfadedLeft); } else { // get entire rect at bottom of screen scrollXDelta += (rect.right - listUnfadedRight); } // make sure we aren't scrolling beyond the end of our children int distanceToRight = rightOfRightChild - listUnfadedRight; scrollXDelta = Math.min(scrollXDelta, distanceToRight); } else if (rect.left < listUnfadedLeft && rect.right < listUnfadedRight) { // need to MOVE UP to get it in view: move up just enough so that // entire rectangle is in view (or at least the first screen // size chunk of it). if (rect.width() > width) { // screen size chunk scrollXDelta -= (listUnfadedRight - rect.right); } else { // entire rect at top scrollXDelta -= (listUnfadedLeft - rect.left); } // make sure we aren't scrolling any further than the top our children int left = getChildAt(0).getLeft(); int deltaToLeft = left - listUnfadedLeft; scrollXDelta = Math.max(scrollXDelta, deltaToLeft); } final boolean scroll = scrollXDelta != 0; if (scroll) { scrollListItemsBy(-scrollXDelta); positionSelector(INVALID_POSITION, child); mSelectedLeft = child.getTop(); invalidate(); } return scroll; } /** * {@inheritDoc} */ @Override protected void fillGap(boolean down) { final int count = getChildCount(); if (down) { int paddingLeft = 0; // if ( ( mGroupFlags & CLIP_TO_PADDING_MASK ) == CLIP_TO_PADDING_MASK ) { // paddingTop = getListPaddingTop(); // } final int startOffset = count > 0 ? getChildAt(count - 1).getRight() + mDividerWidth : paddingLeft; fillRight(mFirstPosition + count, startOffset); correctTooWide(getChildCount()); } else { int paddingRight = 0; // if ( ( mGroupFlags & CLIP_TO_PADDING_MASK ) == CLIP_TO_PADDING_MASK ) { // paddingBottom = getListPaddingBottom(); // } final int startOffset = count > 0 ? getChildAt(0).getLeft() - mDividerWidth : getWidth() - paddingRight; fillLeft(mFirstPosition - 1, startOffset); correctTooSmall(getChildCount()); } } /** * Fills the list from pos down to the end of the list view. * * @param pos The first position to put in the list * @param nextLeft The location where the left of the item associated with pos should be drawn * @return The view that is currently selected, if it happens to be in the range that we draw. */ private View fillRight(int pos, int nextLeft) { View selectedView = null; int end = (getRight() - getLeft()); // if ( ( mGroupFlags & CLIP_TO_PADDING_MASK ) == CLIP_TO_PADDING_MASK ) { // end -= mListPadding.bottom; // } while (nextLeft < end && pos < mItemCount) { // is this the selected item? boolean selected = pos == mSelectedPosition; View child = makeAndAddView(pos, nextLeft, true, mListPadding.top, selected); nextLeft = child.getRight() + mDividerWidth; if (selected) { selectedView = child; } pos++; } setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1); return selectedView; } /** * Fills the list from pos up to the top of the list view. * * @param pos The first position to put in the list * @param nextRight The location where the right of the item associated with pos should be drawn * @return The view that is currently selected */ private View fillLeft(int pos, int nextRight) { View selectedView = null; int end = 0; // if ( ( mGroupFlags & CLIP_TO_PADDING_MASK ) == CLIP_TO_PADDING_MASK ) { // end = mListPadding.top; // } while (nextRight > end && pos >= 0) { // is this the selected item? boolean selected = pos == mSelectedPosition; View child = makeAndAddView(pos, nextRight, false, mListPadding.top, selected); nextRight = child.getLeft() - mDividerWidth; if (selected) { selectedView = child; } pos--; } mFirstPosition = pos + 1; setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1); return selectedView; } /** * Fills the list from top to bottom, starting with mFirstPosition * * @param nextLeft The location where the left of the first item should be drawn * @return The view that is currently selected */ private View fillFromLeft(int nextLeft) { mFirstPosition = Math.min(mFirstPosition, mSelectedPosition); mFirstPosition = Math.min(mFirstPosition, mItemCount - 1); if (mFirstPosition < 0) { mFirstPosition = 0; } return fillRight(mFirstPosition, nextLeft); } /** * Put mSelectedPosition in the middle of the screen and then build up and down from there. This method forces mSelectedPosition * to the center. * * @param childrenLeft Left of the area in which children can be drawn, as measured in pixels * @param childrenRight Right of the area in which children can be drawn, as measured in pixels * @return Currently selected view */ private View fillFromMiddle(int childrenLeft, int childrenRight) { int width = childrenRight - childrenLeft; int position = reconcileSelectedPosition(); View sel = makeAndAddView(position, childrenLeft, true, mListPadding.top, true); mFirstPosition = position; int selWidth = sel.getMeasuredWidth(); if (selWidth <= width) { sel.offsetLeftAndRight((width - selWidth) / 2); } fillBeforeAndAfter(sel, position); if (!mStackFromRight) { correctTooWide(getChildCount()); } else { correctTooSmall(getChildCount()); } return sel; } /** * Once the selected view as been placed, fill up the visible area above and below it. * * @param sel The selected view * @param position The position corresponding to sel */ private void fillBeforeAndAfter(View sel, int position) { final int dividerWidth = mDividerWidth; if (!mStackFromRight) { fillLeft(position - 1, sel.getLeft() - dividerWidth); adjustViewsLeftOrRight(); fillRight(position + 1, sel.getRight() + dividerWidth); } else { fillRight(position + 1, sel.getRight() + dividerWidth); adjustViewsLeftOrRight(); fillLeft(position - 1, sel.getLeft() - dividerWidth); } } /** * Fills the grid based on positioning the new selection at a specific location. The selection may be moved so that it does not * intersect the faded edges. The grid is then filled upwards and downwards from there. * * @param selectedLeft Where the selected item should be * @param childrenLeft Where to start drawing children * @param childrenRight Last pixel where children can be drawn * @return The view that currently has selection */ private View fillFromSelection(int selectedLeft, int childrenLeft, int childrenRight) { int fadingEdgeLength = getHorizontalFadingEdgeLength(); final int selectedPosition = mSelectedPosition; View sel; final int leftSelectionPixel = getLeftSelectionPixel(childrenLeft, fadingEdgeLength, selectedPosition); final int rightSelectionPixel = getRightSelectionPixel(childrenRight, fadingEdgeLength, selectedPosition); sel = makeAndAddView(selectedPosition, selectedLeft, true, mListPadding.top, true); // Some of the newly selected item extends below the bottom of the list if (sel.getRight() > rightSelectionPixel) { // Find space available above the selection into which we can scroll // upwards final int spaceBefore = sel.getLeft() - leftSelectionPixel; // Find space required to bring the bottom of the selected item // fully into view final int spaceAfter = sel.getRight() - rightSelectionPixel; final int offset = Math.min(spaceBefore, spaceAfter); // Now offset the selected item to get it into view sel.offsetLeftAndRight(-offset); } else if (sel.getLeft() < leftSelectionPixel) { // Find space required to bring the top of the selected item fully // into view final int spaceBefore = leftSelectionPixel - sel.getLeft(); // Find space available below the selection into which we can scroll // downwards final int spaceAfter = rightSelectionPixel - sel.getRight(); final int offset = Math.min(spaceBefore, spaceAfter); // Offset the selected item to get it into view sel.offsetLeftAndRight(offset); } // Fill in views above and below fillBeforeAndAfter(sel, selectedPosition); if (!mStackFromRight) { correctTooWide(getChildCount()); } else { correctTooSmall(getChildCount()); } return sel; } /** * Calculate the bottom-most pixel we can draw the selection into * * @param childrenRight Right pixel were children can be drawn * @param fadingEdgeLength Length of the fading edge in pixels, if present * @param selectedPosition The position that will be selected * @return The bottom-most pixel we can draw the selection into */ private int getRightSelectionPixel(int childrenRight, int fadingEdgeLength, int selectedPosition) { int rightSelectionPixel = childrenRight; if (selectedPosition != mItemCount - 1) { rightSelectionPixel -= fadingEdgeLength; } return rightSelectionPixel; } /** * Calculate the left-most pixel we can draw the selection into * * @param childrenLeft Left pixel were children can be drawn * @param fadingEdgeLength Length of the fading edge in pixels, if present * @param selectedPosition The position that will be selected * @return The left-most pixel we can draw the selection into */ private int getLeftSelectionPixel(int childrenLeft, int fadingEdgeLength, int selectedPosition) { // first pixel we can draw the selection into int leftSelectionPixel = childrenLeft; if (selectedPosition > 0) { leftSelectionPixel += fadingEdgeLength; } return leftSelectionPixel; } /** * Smoothly scroll to the specified adapter position. The view will scroll such that the indicated position is displayed. * * @param position Scroll to this adapter position. */ @Override public void smoothScrollToPosition(int position) { super.smoothScrollToPosition(position); } /** * Smoothly scroll to the specified adapter position offset. The view will scroll such that the indicated position is displayed. * * @param offset The amount to offset from the adapter position to scroll to. */ @Override public void smoothScrollByOffset(int offset) { super.smoothScrollByOffset(offset); } /** * Fills the list based on positioning the new selection relative to the old selection. The new selection will be placed at, * above, or below the location of the new selection depending on how the selection is moving. The selection will then be pinned * to the visible part of the screen, excluding the edges that are faded. The list is then filled upwards and downwards from * there. * * @param oldSel The old selected view. Useful for trying to put the new selection in the same place * @param newSel The view that is to become selected. Useful for trying to put the new selection in the same place * @param delta Which way we are moving * @param childrenLeft Where to start drawing children * @param childrenRight Last pixel where children can be drawn * @return The view that currently has selection */ private View moveSelection(View oldSel, View newSel, int delta, int childrenLeft, int childrenRight) { int fadingEdgeLength = getHorizontalFadingEdgeLength(); final int selectedPosition = mSelectedPosition; View sel; final int leftSelectionPixel = getLeftSelectionPixel(childrenLeft, fadingEdgeLength, selectedPosition); final int rightSelectionPixel = getRightSelectionPixel(childrenLeft, fadingEdgeLength, selectedPosition); if (delta > 0) { /* * Case 1: Scrolling down. */ /* * Before After | | | | +-------+ +-------+ | A | | A | | 1 | => +-------+ +-------+ | B | | B | | 2 | +-------+ +-------+ * | | | | * * Try to keep the top of the previously selected item where it was. oldSel = A sel = B */ // Put oldSel (A) where it belongs oldSel = makeAndAddView(selectedPosition - 1, oldSel.getLeft(), true, mListPadding.top, false); final int dividerWidth = mDividerWidth; // Now put the new selection (B) below that sel = makeAndAddView(selectedPosition, oldSel.getRight() + dividerWidth, true, mListPadding.top, true); // Some of the newly selected item extends below the bottom of the list if (sel.getRight() > rightSelectionPixel) { // Find space available above the selection into which we can scroll upwards int spaceBefore = sel.getLeft() - leftSelectionPixel; // Find space required to bring the bottom of the selected item fully into view int spaceAfter = sel.getRight() - rightSelectionPixel; // Don't scroll more than half the height of the list int halfHorizontalSpace = (childrenRight - childrenLeft) / 2; int offset = Math.min(spaceBefore, spaceAfter); offset = Math.min(offset, halfHorizontalSpace); // We placed oldSel, so offset that item oldSel.offsetLeftAndRight(-offset); // Now offset the selected item to get it into view sel.offsetLeftAndRight(-offset); } // Fill in views above and below if (!mStackFromRight) { fillLeft(mSelectedPosition - 2, sel.getLeft() - dividerWidth); adjustViewsLeftOrRight(); fillRight(mSelectedPosition + 1, sel.getRight() + dividerWidth); } else { fillRight(mSelectedPosition + 1, sel.getRight() + dividerWidth); adjustViewsLeftOrRight(); fillLeft(mSelectedPosition - 2, sel.getLeft() - dividerWidth); } } else if (delta < 0) { /* * Case 2: Scrolling up. */ /* * Before After | | | | +-------+ +-------+ | A | | A | +-------+ => | 1 | | B | +-------+ | 2 | | B | +-------+ +-------+ * | | | | * * Try to keep the top of the item about to become selected where it was. newSel = A olSel = B */ if (newSel != null) { // Try to position the top of newSel (A) where it was before it was selected sel = makeAndAddView(selectedPosition, newSel.getLeft(), true, mListPadding.top, true); } else { // If (A) was not on screen and so did not have a view, position // it above the oldSel (B) sel = makeAndAddView(selectedPosition, oldSel.getLeft(), false, mListPadding.top, true); } // Some of the newly selected item extends above the top of the list if (sel.getLeft() < leftSelectionPixel) { // Find space required to bring the top of the selected item fully into view int spaceBefore = leftSelectionPixel - sel.getLeft(); // Find space available below the selection into which we can scroll downwards int spaceAfter = rightSelectionPixel - sel.getRight(); // Don't scroll more than half the height of the list int halfHorizontalSpace = (childrenRight - childrenLeft) / 2; int offset = Math.min(spaceBefore, spaceAfter); offset = Math.min(offset, halfHorizontalSpace); // Offset the selected item to get it into view sel.offsetLeftAndRight(offset); } // Fill in views above and below fillBeforeAndAfter(sel, selectedPosition); } else { int oldLeft = oldSel.getLeft(); /* * Case 3: Staying still */ sel = makeAndAddView(selectedPosition, oldLeft, true, mListPadding.top, true); // We're staying still... if (oldLeft < childrenLeft) { // ... but the top of the old selection was off screen. // (This can happen if the data changes size out from under us) int newRight = sel.getRight(); if (newRight < childrenLeft + 20) { // Not enough visible -- bring it onscreen sel.offsetLeftAndRight(childrenLeft - sel.getLeft()); } } // Fill in views above and below fillBeforeAndAfter(sel, selectedPosition); } return sel; } private class FocusSelector implements Runnable { private int mPosition; private int mPositionLeft; public FocusSelector setup(int position, int left) { mPosition = position; mPositionLeft = left; return this; } @Override public void run() { setSelectionFromLeft(mPosition, mPositionLeft); } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { if (getChildCount() > 0) { View focusedChild = getFocusedChild(); if (focusedChild != null) { final int childPosition = mFirstPosition + indexOfChild(focusedChild); final int childRight = focusedChild.getRight(); final int offset = Math.max(0, childRight - (w - getPaddingLeft())); final int left = focusedChild.getLeft() - offset; if (mFocusSelector == null) { mFocusSelector = new FocusSelector(); } post(mFocusSelector.setup(childPosition, left)); } } super.onSizeChanged(w, h, oldw, oldh); } @TargetApi(11) @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // Sets up mListPadding super.onMeasure(widthMeasureSpec, heightMeasureSpec); int widthMode = MeasureSpec.getMode(widthMeasureSpec); int heightMode = MeasureSpec.getMode(heightMeasureSpec); int widthSize = MeasureSpec.getSize(widthMeasureSpec); int heightSize = MeasureSpec.getSize(heightMeasureSpec); int childWidth = 0; int childHeight = 0; int childState = 0; mItemCount = mAdapter == null ? 0 : mAdapter.getCount(); if (mItemCount > 0 && (widthMode == MeasureSpec.UNSPECIFIED || heightMode == MeasureSpec.UNSPECIFIED)) { if (LOG_ENABLED) { Log.d(LOG_TAG, "let's measure a scrap child"); } final View child = obtainView(0, mIsScrap); measureScrapChildWidth(child, 0, heightMeasureSpec); childWidth = child.getMeasuredWidth(); childHeight = child.getMeasuredHeight(); if (android.os.Build.VERSION.SDK_INT >= 11) { childState = combineMeasuredStates(childState, child.getMeasuredState()); } if (recycleOnMeasure() && mRecycler.shouldRecycleViewType(((LayoutParams) child.getLayoutParams()).viewType)) { mRecycler.addScrapView(child, -1); } } if (heightMode == MeasureSpec.UNSPECIFIED) { heightSize = mListPadding.top + mListPadding.bottom + childHeight + getHorizontalScrollbarHeight(); } else if (heightMode == MeasureSpec.AT_MOST && mItemCount > 0 && mMeasureWithChild > -1) { // TODO: need a better way in case of "wrap_content" int[] result = measureWithLargeChildren(heightMeasureSpec, mMeasureWithChild, mMeasureWithChild, widthSize, heightSize, -1); heightSize = result[1]; } else { // match_parent, dimension if (android.os.Build.VERSION.SDK_INT >= 11) { heightSize |= (childState & MEASURED_STATE_MASK); } } if (widthMode == MeasureSpec.UNSPECIFIED) { widthSize = mListPadding.left + mListPadding.right + childWidth + getHorizontalFadingEdgeLength() * 2; } if (widthMode == MeasureSpec.AT_MOST) { widthSize = measureWidthOfChildren(heightMeasureSpec, 0, NO_POSITION, widthSize, -1); } if (LOG_ENABLED) { Log.d(LOG_TAG, "final size: " + widthSize + "x" + heightSize); } setMeasuredDimension(widthSize, heightSize); mHeightMeasureSpec = heightMeasureSpec; } private void measureScrapChildWidth(View child, int position, int heightMeasureSpec) { LayoutParams p = (LayoutParams) child.getLayoutParams(); if (p == null) { p = (AbsHListView.LayoutParams) generateDefaultLayoutParams(); child.setLayoutParams(p); } p.viewType = mAdapter.getItemViewType(position); p.forceAdd = true; int childHeightSpec = ViewGroup.getChildMeasureSpec(heightMeasureSpec, mListPadding.top + mListPadding.bottom, p.height); int lpWidth = p.width; int childWidthSpec; if (lpWidth > 0) { childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY); } else { childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); } child.measure(childWidthSpec, childHeightSpec); } public int[] measureChild(View child) { measureItem(child); int w = child.getMeasuredWidth(); int h = child.getMeasuredHeight(); return new int[] { w, h }; } /** * @return True to recycle the views used to measure this ListView in UNSPECIFIED/AT_MOST modes, false otherwise. * @hide */ @ViewDebug.ExportedProperty(category = "list") protected boolean recycleOnMeasure() { return true; } /** * Measures the height of the given range of children (inclusive) and returns the height with this ListView's padding and divider * heights included. If maxHeight is provided, the measuring will stop when the current height reaches maxHeight. * * @param heightMeasureSpec The height measure spec to be given to a child's {@link View#measure(int, int)}. * @param startPosition The position of the first child to be shown. * @param endPosition The (inclusive) position of the last child to be shown. Specify {@link #NO_POSITION} if the last child should be the * last available child from the adapter. * @param maxWidth The maximum height that will be returned (if all the children don't fit in this value, this value will be returned). * @param disallowPartialChildPosition In general, whether the returned height should only contain entire children. This is more powerful--it is the first * inclusive position at which partial children will not be allowed. Example: it looks nice to have at least 3 * completely visible children, and in portrait this will most likely fit; but in landscape there could be times when * even 2 children can not be completely shown, so a value of 2 (remember, inclusive) would be good (assuming * startPosition is 0). * @return The height of this ListView with the given children. */ final int measureWidthOfChildren(int heightMeasureSpec, int startPosition, int endPosition, final int maxWidth, int disallowPartialChildPosition) { if (LOG_ENABLED) { Log.i(LOG_TAG, "measureWidthOfChildren, from " + startPosition + " to " + endPosition); } final ListAdapter adapter = mAdapter; if (adapter == null) { return mListPadding.left + mListPadding.right; } // Include the padding of the list int returnedWidth = mListPadding.left + mListPadding.right; final int dividerWidth = ((mDividerWidth > 0) && mDivider != null) ? mDividerWidth : 0; // The previous height value that was less than maxHeight and contained // no partial children int prevWidthWithoutPartialChild = 0; int i; View child; // mItemCount - 1 since endPosition parameter is inclusive endPosition = (endPosition == NO_POSITION) ? adapter.getCount() - 1 : endPosition; final AbsHListView.RecycleBin recycleBin = mRecycler; final boolean recyle = recycleOnMeasure(); final boolean[] isScrap = mIsScrap; for (i = startPosition; i <= endPosition; ++i) { child = obtainView(i, isScrap); measureScrapChildWidth(child, i, heightMeasureSpec); if (i > 0) { // Count the divider for all but one child returnedWidth += dividerWidth; } // Recycle the view before we possibly return from the method if (recyle && recycleBin.shouldRecycleViewType(((LayoutParams) child.getLayoutParams()).viewType)) { recycleBin.addScrapView(child, -1); } returnedWidth += child.getMeasuredWidth(); if (returnedWidth >= maxWidth) { // We went over, figure out which height to return. If returnedHeight > maxHeight, // then the i'th position did not fit completely. return (disallowPartialChildPosition >= 0) // Disallowing is enabled (> -1) && (i > disallowPartialChildPosition) // We've past the min pos && (prevWidthWithoutPartialChild > 0) // We have a prev height && (returnedWidth != maxWidth) // i'th child did not fit completely ? prevWidthWithoutPartialChild : maxWidth; } if ((disallowPartialChildPosition >= 0) && (i >= disallowPartialChildPosition)) { prevWidthWithoutPartialChild = returnedWidth; } } // At this point, we went through the range of children, and they each // completely fit, so return the returnedHeight return returnedWidth; } final int[] measureWithLargeChildren(int heightMeasureSpec, int startPosition, int endPosition, final int maxWidth, final int maxHeight, int disallowPartialChildPosition) { if (LOG_ENABLED) { Log.i(LOG_TAG, "measureWithLargeChildren, from " + startPosition + " to " + endPosition); } final ListAdapter adapter = mAdapter; if (adapter == null) { return new int[] { mListPadding.left + mListPadding.right, mListPadding.top + mListPadding.bottom }; } // Include the padding of the list int returnedWidth = mListPadding.left + mListPadding.right; int returnedHeight = mListPadding.top + mListPadding.bottom; final int dividerWidth = ((mDividerWidth > 0) && mDivider != null) ? mDividerWidth : 0; int childWidth = 0; int childHeight = 0; int i; View child; // mItemCount - 1 since endPosition parameter is inclusive endPosition = (endPosition == NO_POSITION) ? adapter.getCount() - 1 : endPosition; final AbsHListView.RecycleBin recycleBin = mRecycler; final boolean recyle = recycleOnMeasure(); final boolean[] isScrap = mIsScrap; for (i = startPosition; i <= endPosition; ++i) { child = obtainView(i, isScrap); measureScrapChildWidth(child, i, heightMeasureSpec); // Recycle the view before we possibly return from the method if (recyle && recycleBin.shouldRecycleViewType(((LayoutParams) child.getLayoutParams()).viewType)) { recycleBin.addScrapView(child, -1); } childWidth = Math.max(childWidth, child.getMeasuredWidth() + dividerWidth); childHeight = Math.max(childHeight, child.getMeasuredHeight()); } returnedWidth += childWidth; returnedHeight += childHeight; return new int[] { Math.min(returnedWidth, maxWidth), Math.min(returnedHeight, maxHeight) }; } @Override protected int findMotionCol(int x) { int childCount = getChildCount(); if (childCount > 0) { if (!mStackFromRight) { for (int i = 0; i < childCount; i++) { View v = getChildAt(i); if (x <= v.getRight()) { return mFirstPosition + i; } } } else { for (int i = childCount - 1; i >= 0; i--) { View v = getChildAt(i); if (x >= v.getLeft()) { return mFirstPosition + i; } } } } return INVALID_POSITION; } /** * Put a specific item at a specific location on the screen and then build up and down from there. * * @param position The reference view to use as the starting point * @param left Pixel offset from the left of this view to the top of the reference view. * @return The selected view, or null if the selected view is outside the visible area. */ private View fillSpecific(int position, int left) { boolean tempIsSelected = position == mSelectedPosition; View temp = makeAndAddView(position, left, true, mListPadding.top, tempIsSelected); // Possibly changed again in fillUp if we add rows above this one. mFirstPosition = position; View before; View after; final int dividerWidth = mDividerWidth; if (!mStackFromRight) { before = fillLeft(position - 1, temp.getLeft() - dividerWidth); // This will correct for the top of the first view not touching the top of the list adjustViewsLeftOrRight(); after = fillRight(position + 1, temp.getRight() + dividerWidth); int childCount = getChildCount(); if (childCount > 0) { correctTooWide(childCount); } } else { after = fillRight(position + 1, temp.getRight() + dividerWidth); // This will correct for the bottom of the last view not touching the bottom of the list adjustViewsLeftOrRight(); before = fillLeft(position - 1, temp.getLeft() - dividerWidth); int childCount = getChildCount(); if (childCount > 0) { correctTooSmall(childCount); } } if (tempIsSelected) { return temp; } else if (before != null) { return before; } else { return after; } } /** * Check if we have dragged the right of the list too wide (we have pushed the left element off the left of the screen when we did * not need to). Correct by sliding everything back down. * * @param childCount Number of children */ private void correctTooWide(int childCount) { // First see if the last item is visible. If it is not, it is OK for the // top of the list to be pushed up. int lastPosition = mFirstPosition + childCount - 1; if (lastPosition == mItemCount - 1 && childCount > 0) { // Get the last child ... final View lastChild = getChildAt(childCount - 1); // ... and its bottom edge final int lastRight = lastChild.getRight(); // This is bottom of our drawable area final int end = (getRight() - getLeft()) - mListPadding.right; // This is how far the bottom edge of the last view is from the bottom of the // drawable area int rightOffset = end - lastRight; View firstChild = getChildAt(0); final int firstLeft = firstChild.getLeft(); // Make sure we are 1) Too high, and 2) Either there are more rows above the // first row or the first row is scrolled off the top of the drawable area if (rightOffset > 0 && (mFirstPosition > 0 || firstLeft < mListPadding.top)) { if (mFirstPosition == 0) { // Don't pull the top too far down rightOffset = Math.min(rightOffset, mListPadding.top - firstLeft); } // Move everything down offsetChildrenLeftAndRight(rightOffset); if (mFirstPosition > 0) { // Fill the gap that was opened above mFirstPosition with more rows, if // possible fillLeft(mFirstPosition - 1, firstChild.getLeft() - mDividerWidth); // Close up the remaining gap adjustViewsLeftOrRight(); } } } } /** * Check if we have dragged the right of the list too low (we have pushed the right element off the right of the screen when * we did not need to). Correct by sliding everything back up. * * @param childCount Number of children */ private void correctTooSmall(int childCount) { // First see if the first item is visible. If it is not, it is OK for the // bottom of the list to be pushed down. if (mFirstPosition == 0 && childCount > 0) { // Get the first child ... final View firstChild = getChildAt(0); // ... and its top edge final int firstLeft = firstChild.getLeft(); // This is top of our drawable area final int start = mListPadding.left; // This is bottom of our drawable area final int end = (getRight() - getLeft()) - mListPadding.right; // This is how far the top edge of the first view is from the top of the // drawable area int leftOffset = firstLeft - start; View lastChild = getChildAt(childCount - 1); final int lastRight = lastChild.getRight(); int lastPosition = mFirstPosition + childCount - 1; // Make sure we are 1) Too low, and 2) Either there are more rows below the // last row or the last row is scrolled off the bottom of the drawable area if (leftOffset > 0) { if (lastPosition < mItemCount - 1 || lastRight > end) { if (lastPosition == mItemCount - 1) { // Don't pull the bottom too far up leftOffset = Math.min(leftOffset, lastRight - end); } // Move everything up offsetChildrenLeftAndRight(-leftOffset); if (lastPosition < mItemCount - 1) { // Fill the gap that was opened below the last position with more rows, if // possible fillRight(lastPosition + 1, lastChild.getRight() + mDividerWidth); // Close up the remaining gap adjustViewsLeftOrRight(); } } else if (lastPosition == mItemCount - 1) { adjustViewsLeftOrRight(); } } } } @Override protected void layoutChildren() { final boolean blockLayoutRequests = mBlockLayoutRequests; if (!blockLayoutRequests) { mBlockLayoutRequests = true; } else { return; } try { super.layoutChildren(); invalidate(); if (mAdapter == null) { resetList(); invokeOnItemScrollListener(); return; } int childrenLeft = mListPadding.left; int childrenRight = getRight() - getLeft() - mListPadding.right; int childCount = getChildCount(); int index = 0; int delta = 0; View sel; View oldSel = null; View oldFirst = null; View newSel = null; View focusLayoutRestoreView = null; // AccessibilityNodeInfo accessibilityFocusLayoutRestoreNode = null; // View accessibilityFocusLayoutRestoreView = null; // int accessibilityFocusPosition = INVALID_POSITION; // Remember stuff we will need down below switch (mLayoutMode) { case LAYOUT_SET_SELECTION: index = mNextSelectedPosition - mFirstPosition; if (index >= 0 && index < childCount) { newSel = getChildAt(index); } break; case LAYOUT_FORCE_LEFT: case LAYOUT_FORCE_RIGHT: case LAYOUT_SPECIFIC: case LAYOUT_SYNC: break; case LAYOUT_MOVE_SELECTION: default: // Remember the previously selected view index = mSelectedPosition - mFirstPosition; if (index >= 0 && index < childCount) { oldSel = getChildAt(index); } // Remember the previous first child oldFirst = getChildAt(0); if (mNextSelectedPosition >= 0) { delta = mNextSelectedPosition - mSelectedPosition; } // Caution: newSel might be null newSel = getChildAt(index + delta); } boolean dataChanged = mDataChanged; if (dataChanged) { handleDataChanged(); } // Handle the empty set by removing all views that are visible // and calling it a day if (mItemCount == 0) { resetList(); invokeOnItemScrollListener(); return; } else if (mItemCount != mAdapter.getCount()) { throw new IllegalStateException("The content of the adapter has changed but " + "ListView did not receive a notification. Make sure the content of " + "your adapter is not modified from a background thread, but only " + "from the UI thread. [in ListView(" + getId() + ", " + getClass() + ") with Adapter(" + mAdapter.getClass() + ")]"); } setSelectedPositionInt(mNextSelectedPosition); // Pull all children into the RecycleBin. // These views will be reused if possible final int firstPosition = mFirstPosition; final RecycleBin recycleBin = mRecycler; // reset the focus restoration View focusLayoutRestoreDirectChild = null; // Don't put header or footer views into the Recycler. Those are // already cached in mHeaderViews; if (dataChanged) { for (int i = 0; i < childCount; i++) { recycleBin.addScrapView(getChildAt(i), firstPosition + i); } } else { recycleBin.fillActiveViews(childCount, firstPosition); } // take focus back to us temporarily to avoid the eventual // call to clear focus when removing the focused child below // from messing things up when ViewAncestor assigns focus back // to someone else final View focusedChild = getFocusedChild(); if (focusedChild != null) { // TODO: in some cases focusedChild.getParent() == null // we can remember the focused view to restore after relayout if the // data hasn't changed, or if the focused position is a header or footer if (!dataChanged || isDirectChildHeaderOrFooter(focusedChild)) { focusLayoutRestoreDirectChild = focusedChild; // remember the specific view that had focus focusLayoutRestoreView = findFocus(); if (focusLayoutRestoreView != null) { // tell it we are going to mess with it focusLayoutRestoreView.onStartTemporaryDetach(); } } requestFocus(); } /* * // Remember which child, if any, had accessibility focus. final ViewRootImpl viewRootImpl = getViewRootImpl(); if ( * viewRootImpl != null ) { final View accessFocusedView = viewRootImpl.getAccessibilityFocusedHost(); if ( * accessFocusedView != null ) { final View accessFocusedChild = findAccessibilityFocusedChild( accessFocusedView ); if ( * accessFocusedChild != null ) { if ( !dataChanged || isDirectChildHeaderOrFooter( accessFocusedChild ) ) { // If the * views won't be changing, try to maintain // focus on the current view host and (if // applicable) its virtual view. * accessibilityFocusLayoutRestoreView = accessFocusedView; accessibilityFocusLayoutRestoreNode = viewRootImpl * .getAccessibilityFocusedVirtualView(); } else { // Otherwise, try to maintain focus at the same // position. * accessibilityFocusPosition = getPositionForView( accessFocusedChild ); } } } } */ // Clear out old views detachAllViewsFromParent(); recycleBin.removeSkippedScrap(); switch (mLayoutMode) { case LAYOUT_SET_SELECTION: if (newSel != null) { sel = fillFromSelection(newSel.getLeft(), childrenLeft, childrenRight); } else { sel = fillFromMiddle(childrenLeft, childrenRight); } break; case LAYOUT_SYNC: sel = fillSpecific(mSyncPosition, mSpecificLeft); break; case LAYOUT_FORCE_RIGHT: sel = fillLeft(mItemCount - 1, childrenRight); adjustViewsLeftOrRight(); break; case LAYOUT_FORCE_LEFT: mFirstPosition = 0; sel = fillFromLeft(childrenLeft); adjustViewsLeftOrRight(); break; case LAYOUT_SPECIFIC: sel = fillSpecific(reconcileSelectedPosition(), mSpecificLeft); break; case LAYOUT_MOVE_SELECTION: sel = moveSelection(oldSel, newSel, delta, childrenLeft, childrenRight); break; default: if (childCount == 0) { if (!mStackFromRight) { final int position = lookForSelectablePosition(0, true); setSelectedPositionInt(position); sel = fillFromLeft(childrenLeft); } else { final int position = lookForSelectablePosition(mItemCount - 1, false); setSelectedPositionInt(position); sel = fillLeft(mItemCount - 1, childrenRight); } } else { if (mSelectedPosition >= 0 && mSelectedPosition < mItemCount) { sel = fillSpecific(mSelectedPosition, oldSel == null ? childrenLeft : oldSel.getLeft()); } else if (mFirstPosition < mItemCount) { sel = fillSpecific(mFirstPosition, oldFirst == null ? childrenLeft : oldFirst.getLeft()); } else { sel = fillSpecific(0, childrenLeft); } } break; } // Flush any cached views that did not get reused above recycleBin.scrapActiveViews(); if (sel != null) { // the current selected item should get focus if items // are focusable if (mItemsCanFocus && hasFocus() && !sel.hasFocus()) { final boolean focusWasTaken = (sel == focusLayoutRestoreDirectChild && focusLayoutRestoreView != null && focusLayoutRestoreView.requestFocus()) || sel.requestFocus(); if (!focusWasTaken) { // selected item didn't take focus, fine, but still want // to make sure something else outside of the selected view // has focus final View focused = getFocusedChild(); if (focused != null) { focused.clearFocus(); } positionSelector(INVALID_POSITION, sel); } else { sel.setSelected(false); mSelectorRect.setEmpty(); } } else { positionSelector(INVALID_POSITION, sel); } mSelectedLeft = sel.getLeft(); } else { if (mTouchMode > TOUCH_MODE_DOWN && mTouchMode < TOUCH_MODE_SCROLL) { View child = getChildAt(mMotionPosition - mFirstPosition); if (child != null) positionSelector(mMotionPosition, child); } else { mSelectedLeft = 0; mSelectorRect.setEmpty(); } // even if there is not selected position, we may need to restore // focus (i.e. something focusable in touch mode) if (hasFocus() && focusLayoutRestoreView != null) { focusLayoutRestoreView.requestFocus(); } } // Attempt to restore accessibility focus. // if ( accessibilityFocusLayoutRestoreNode != null ) { // accessibilityFocusLayoutRestoreNode.performAction(AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS ); // } else if ( accessibilityFocusLayoutRestoreView != null ) { // this method is marked as hidden. Shame on you google! // accessibilityFocusLayoutRestoreView.requestAccessibilityFocus(); // } else if ( accessibilityFocusPosition != INVALID_POSITION ) { // Bound the position within the visible children. // final int position = MathUtils.constrain( ( accessibilityFocusPosition - mFirstPosition ), 0, ( getChildCount() - 1 ) ); // final View restoreView = getChildAt( position ); // if ( restoreView != null ) { // this method is marked as hidden. Shame on you google! // restoreView.requestAccessibilityFocus(); // } // } // tell focus view we are done mucking with it, if it is still in // our view hierarchy. if (focusLayoutRestoreView != null && focusLayoutRestoreView.getWindowToken() != null) { focusLayoutRestoreView.onFinishTemporaryDetach(); } mLayoutMode = LAYOUT_NORMAL; mDataChanged = false; if (mPositionScrollAfterLayout != null) { post(mPositionScrollAfterLayout); mPositionScrollAfterLayout = null; } mNeedSync = false; setNextSelectedPositionInt(mSelectedPosition); updateScrollIndicators(); if (mItemCount > 0) { checkSelectionChanged(); } invokeOnItemScrollListener(); } finally { if (!blockLayoutRequests) { mBlockLayoutRequests = false; } } } /** * @param focusedView the view that has accessibility focus. * @return the direct child that contains accessibility focus. */ @SuppressWarnings("unused") private View findAccessibilityFocusedChild(View focusedView) { ViewParent viewParent = focusedView.getParent(); while ((viewParent instanceof View) && (viewParent != this)) { focusedView = (View) viewParent; viewParent = viewParent.getParent(); } if (!(viewParent instanceof View)) { return null; } return focusedView; } /** * @param child a direct child of this list. * @return Whether child is a header or footer view. */ private boolean isDirectChildHeaderOrFooter(View child) { final ArrayList<FixedViewInfo> headers = mHeaderViewInfos; final int numHeaders = headers.size(); for (int i = 0; i < numHeaders; i++) { if (child == headers.get(i).view) { return true; } } final ArrayList<FixedViewInfo> footers = mFooterViewInfos; final int numFooters = footers.size(); for (int i = 0; i < numFooters; i++) { if (child == footers.get(i).view) { return true; } } return false; } /** * Obtain the view and add it to our list of children. The view can be made fresh, converted from an unused view, or used as is * if it was in the recycle bin. * * @param position Logical position in the list * @param x Left or right edge of the view to add * @param flow If flow is true, align left edge to x. If false, align right edge to x. * @param childrenTop Top edge where children should be positioned * @param selected Is this position selected? * @return View that was added */ private View makeAndAddView(int position, int x, boolean flow, int childrenTop, boolean selected) { View child; if (!mDataChanged) { // Try to use an existing view for this position child = mRecycler.getActiveView(position); if (child != null) { // Found it -- we're using an existing child // This just needs to be positioned setupChild(child, position, x, flow, childrenTop, selected, true); return child; } } // Make a new view for this position, or convert an unused view if possible child = obtainView(position, mIsScrap); // This needs to be positioned and measured setupChild(child, position, x, flow, childrenTop, selected, mIsScrap[0]); return child; } /** * Add a view as a child and make sure it is measured (if necessary) and positioned properly. * * @param child The view to add * @param position The position of this child * @param x The x position relative to which this view will be positioned * @param flowDown If true, align left edge to x. If false, align right edge to x. * @param childrenTop Top edge where children should be positioned * @param selected Is this position selected? * @param recycled Has this view been pulled from the recycle bin? If so it does not need to be remeasured. */ @TargetApi(11) private void setupChild(View child, int position, int x, boolean flowDown, int childrenTop, boolean selected, boolean recycled) { final boolean isSelected = selected && shouldShowSelector(); final boolean updateChildSelected = isSelected != child.isSelected(); final int mode = mTouchMode; final boolean isPressed = mode > TOUCH_MODE_DOWN && mode < TOUCH_MODE_SCROLL && mMotionPosition == position; final boolean updateChildPressed = isPressed != child.isPressed(); final boolean needToMeasure = !recycled || updateChildSelected || child.isLayoutRequested(); // Respect layout params that are already in the view. Otherwise make some up... // noinspection unchecked AbsHListView.LayoutParams p = (AbsHListView.LayoutParams) child.getLayoutParams(); if (p == null) { p = (AbsHListView.LayoutParams) generateDefaultLayoutParams(); } p.viewType = mAdapter.getItemViewType(position); if ((recycled && !p.forceAdd) || (p.recycledHeaderFooter && p.viewType == AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER)) { attachViewToParent(child, flowDown ? -1 : 0, p); } else { p.forceAdd = false; if (p.viewType == AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { p.recycledHeaderFooter = true; } addViewInLayout(child, flowDown ? -1 : 0, p, true); } if (updateChildSelected) { child.setSelected(isSelected); } if (updateChildPressed) { child.setPressed(isPressed); } if (mChoiceMode != ListView.CHOICE_MODE_NONE && mCheckStates != null) { if (child instanceof Checkable) { ((Checkable) child).setChecked(mCheckStates.get(position, false)); } else if (android.os.Build.VERSION.SDK_INT >= 11) { child.setActivated(mCheckStates.get(position, false)); } } if (needToMeasure) { int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec, mListPadding.top + mListPadding.bottom, p.height); int lpWidth = p.width; int childWidthSpec; if (lpWidth > 0) { childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY); } else { childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); } child.measure(childWidthSpec, childHeightSpec); } else { cleanupLayoutState(child); } final int w = child.getMeasuredWidth(); final int h = child.getMeasuredHeight(); final int childLeft = flowDown ? x : x - w; if (needToMeasure) { final int childBottom = childrenTop + h; final int childRight = childLeft + w; child.layout(childLeft, childrenTop, childRight, childBottom); } else { child.offsetLeftAndRight(childLeft - child.getLeft()); child.offsetTopAndBottom(childrenTop - child.getTop()); } if (mCachingStarted && !child.isDrawingCacheEnabled()) { child.setDrawingCacheEnabled(true); } if (android.os.Build.VERSION.SDK_INT >= 11) { if (recycled && (((AbsHListView.LayoutParams) child.getLayoutParams()).scrappedFromPosition) != position) { child.jumpDrawablesToCurrentState(); } } } @Override protected boolean canAnimate() { return super.canAnimate() && mItemCount > 0; } /** * Sets the currently selected item. If in touch mode, the item will not be selected but it will still be positioned * appropriately. If the specified selection position is less than 0, then the item at position 0 will be selected. * * @param position Index (starting at 0) of the data item to be selected. */ @Override public void setSelection(int position) { setSelectionFromLeft(position, 0); } /** * Sets the selected item and positions the selection x pixels from the left edge of the ListView. (If in touch mode, the item * will not be selected but it will still be positioned appropriately.) * * @param position Index (starting at 0) of the data item to be selected. * @param x The distance from the left edge of the ListView (plus padding) that the item will be positioned. */ public void setSelectionFromLeft(int position, int x) { if (mAdapter == null) { return; } if (!isInTouchMode()) { position = lookForSelectablePosition(position, true); if (position >= 0) { setNextSelectedPositionInt(position); } } else { mResurrectToPosition = position; } if (position >= 0) { mLayoutMode = LAYOUT_SPECIFIC; mSpecificLeft = mListPadding.left + x; if (mNeedSync) { mSyncPosition = position; mSyncColId = mAdapter.getItemId(position); } if (mPositionScroller != null) { mPositionScroller.stop(); } requestLayout(); } } /** * Makes the item at the supplied position selected. * * @param position the position of the item to select */ @Override public void setSelectionInt(int position) { setNextSelectedPositionInt(position); boolean awakeScrollbars = false; final int selectedPosition = mSelectedPosition; if (selectedPosition >= 0) { if (position == selectedPosition - 1) { awakeScrollbars = true; } else if (position == selectedPosition + 1) { awakeScrollbars = true; } } if (mPositionScroller != null) { mPositionScroller.stop(); } layoutChildren(); if (awakeScrollbars) { awakenScrollBars(); } } /** * Find a position that can be selected (i.e., is not a separator). * * @param position The starting position to look at. * @param lookDown Whether to look down for other positions. * @return The next selectable position starting at position and then searching either up or down. Returns * {@link #INVALID_POSITION} if nothing can be found. */ @Override protected int lookForSelectablePosition(int position, boolean lookDown) { final ListAdapter adapter = mAdapter; if (adapter == null || isInTouchMode()) { return INVALID_POSITION; } final int count = adapter.getCount(); if (!mAreAllItemsSelectable) { if (lookDown) { position = Math.max(0, position); while (position < count && !adapter.isEnabled(position)) { position++; } } else { position = Math.min(position, count - 1); while (position >= 0 && !adapter.isEnabled(position)) { position--; } } if (position < 0 || position >= count) { return INVALID_POSITION; } return position; } else { if (position < 0 || position >= count) { return INVALID_POSITION; } return position; } } /** * setSelectionAfterHeaderView set the selection to be the first list item after the header views. */ public void setSelectionAfterHeaderView() { final int count = mHeaderViewInfos.size(); if (count > 0) { mNextSelectedPosition = 0; return; } if (mAdapter != null) { setSelection(count); } else { mNextSelectedPosition = count; mLayoutMode = LAYOUT_SET_SELECTION; } } @Override public boolean dispatchKeyEvent(KeyEvent event) { // Dispatch in the normal way boolean handled = super.dispatchKeyEvent(event); if (!handled) { // If we didn't handle it... View focused = getFocusedChild(); if (focused != null && event.getAction() == KeyEvent.ACTION_DOWN) { // ... and our focused child didn't handle it // ... give it to ourselves so we can scroll if necessary handled = onKeyDown(event.getKeyCode(), event); } } return handled; } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { return commonKey(keyCode, 1, event); } @Override public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) { return commonKey(keyCode, repeatCount, event); } @Override public boolean onKeyUp(int keyCode, KeyEvent event) { return commonKey(keyCode, 1, event); } @TargetApi(11) private boolean commonKey(int keyCode, int count, KeyEvent event) { if (mAdapter == null || !mIsAttached) { return false; } if (mDataChanged) { layoutChildren(); } if (android.os.Build.VERSION.SDK_INT < 11) { return false; } boolean handled = false; int action = event.getAction(); if (action != KeyEvent.ACTION_UP) { switch (keyCode) { case KeyEvent.KEYCODE_DPAD_UP: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded(); if (!handled) { while (count-- > 0) { if (arrowScroll(FOCUS_UP)) { handled = true; } else { break; } } } } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); } break; case KeyEvent.KEYCODE_DPAD_DOWN: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded(); if (!handled) { while (count-- > 0) { if (arrowScroll(FOCUS_DOWN)) { handled = true; } else { break; } } } } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); } break; case KeyEvent.KEYCODE_DPAD_LEFT: if (event.hasNoModifiers()) { handled = handleHorizontalFocusWithinListItem(View.FOCUS_LEFT); } break; case KeyEvent.KEYCODE_DPAD_RIGHT: if (event.hasNoModifiers()) { handled = handleHorizontalFocusWithinListItem(View.FOCUS_RIGHT); } break; case KeyEvent.KEYCODE_DPAD_CENTER: case KeyEvent.KEYCODE_ENTER: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded(); if (!handled && event.getRepeatCount() == 0 && getChildCount() > 0) { keyPressed(); handled = true; } } break; case KeyEvent.KEYCODE_SPACE: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_DOWN); } else if (event.hasModifiers(KeyEvent.META_SHIFT_ON)) { handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_UP); } handled = true; break; case KeyEvent.KEYCODE_PAGE_UP: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_UP); } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); } break; case KeyEvent.KEYCODE_PAGE_DOWN: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_DOWN); } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); } break; case KeyEvent.KEYCODE_MOVE_HOME: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); } break; case KeyEvent.KEYCODE_MOVE_END: if (event.hasNoModifiers()) { handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); } break; case KeyEvent.KEYCODE_TAB: break; } } if (handled) { return true; } switch (action) { case KeyEvent.ACTION_DOWN: return super.onKeyDown(keyCode, event); case KeyEvent.ACTION_UP: return super.onKeyUp(keyCode, event); case KeyEvent.ACTION_MULTIPLE: return super.onKeyMultiple(keyCode, count, event); default: // shouldn't happen return false; } } /** * Scrolls left or right by the number of items currently present on screen. * * @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN} * @return whether selection was moved */ boolean pageScroll(int direction) { int nextPage = -1; boolean down = false; if (direction == FOCUS_UP) { nextPage = Math.max(0, mSelectedPosition - getChildCount() - 1); } else if (direction == FOCUS_DOWN) { nextPage = Math.min(mItemCount - 1, mSelectedPosition + getChildCount() - 1); down = true; } if (nextPage >= 0) { int position = lookForSelectablePosition(nextPage, down); if (position >= 0) { mLayoutMode = LAYOUT_SPECIFIC; mSpecificLeft = getPaddingLeft() + getHorizontalFadingEdgeLength(); if (down && position > mItemCount - getChildCount()) { mLayoutMode = LAYOUT_FORCE_RIGHT; } if (!down && position < getChildCount()) { mLayoutMode = LAYOUT_FORCE_LEFT; } setSelectionInt(position); invokeOnItemScrollListener(); if (!awakenScrollBars()) { invalidate(); } return true; } } return false; } /** * Go to the last or first item if possible (not worrying about panning across or navigating within the internal focus of the * currently selected item.) * * @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN} * @return whether selection was moved */ boolean fullScroll(int direction) { boolean moved = false; if (direction == FOCUS_UP) { if (mSelectedPosition != 0) { int position = lookForSelectablePosition(0, true); if (position >= 0) { mLayoutMode = LAYOUT_FORCE_LEFT; setSelectionInt(position); invokeOnItemScrollListener(); } moved = true; } } else if (direction == FOCUS_DOWN) { if (mSelectedPosition < mItemCount - 1) { int position = lookForSelectablePosition(mItemCount - 1, true); if (position >= 0) { mLayoutMode = LAYOUT_FORCE_RIGHT; setSelectionInt(position); invokeOnItemScrollListener(); } moved = true; } } if (moved && !awakenScrollBars()) { awakenScrollBars(); invalidate(); } return moved; } /** * To avoid horizontal focus searches changing the selected item, we manually focus search within the selected item (as * applicable), and prevent focus from jumping to something within another item. * * @param direction one of {View.FOCUS_LEFT, View.FOCUS_RIGHT} * @return Whether this consumes the key event. */ private boolean handleHorizontalFocusWithinListItem(int direction) { // TODO: implement this if (direction != View.FOCUS_LEFT && direction != View.FOCUS_RIGHT) { throw new IllegalArgumentException("direction must be one of" + " {View.FOCUS_LEFT, View.FOCUS_RIGHT}"); } final int numChildren = getChildCount(); if (mItemsCanFocus && numChildren > 0 && mSelectedPosition != INVALID_POSITION) { final View selectedView = getSelectedView(); if (selectedView != null && selectedView.hasFocus() && selectedView instanceof ViewGroup) { final View currentFocus = selectedView.findFocus(); final View nextFocus = FocusFinder.getInstance().findNextFocus((ViewGroup) selectedView, currentFocus, direction); if (nextFocus != null) { // do the math to get interesting rect in next focus' coordinates currentFocus.getFocusedRect(mTempRect); offsetDescendantRectToMyCoords(currentFocus, mTempRect); offsetRectIntoDescendantCoords(nextFocus, mTempRect); if (nextFocus.requestFocus(direction, mTempRect)) { return true; } } // we are blocking the key from being handled (by returning true) // if the global result is going to be some other view within this // list. this is to acheive the overall goal of having // horizontal d-pad navigation remain in the current item. final View globalNextFocus = FocusFinder.getInstance().findNextFocus((ViewGroup) getRootView(), currentFocus, direction); if (globalNextFocus != null) { return isViewAncestorOf(globalNextFocus, this); } } } return false; } /** * Scrolls to the next or previous item if possible. * * @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN} * @return whether selection was moved */ boolean arrowScroll(int direction) { try { mInLayout = true; final boolean handled = arrowScrollImpl(direction); if (handled) { playSoundEffect(SoundEffectConstants.getContantForFocusDirection(direction)); } return handled; } finally { mInLayout = false; } } /** * Handle an arrow scroll going up or down. Take into account whether items are selectable, whether there are focusable items * etc. * * @param direction Either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @return Whether any scrolling, selection or focus change occured. */ private boolean arrowScrollImpl(int direction) { if (getChildCount() <= 0) { return false; } View selectedView = getSelectedView(); int selectedPos = mSelectedPosition; int nextSelectedPosition = lookForSelectablePositionOnScreen(direction); int amountToScroll = amountToScroll(direction, nextSelectedPosition); // if we are moving focus, we may OVERRIDE the default behavior final ArrowScrollFocusResult focusResult = mItemsCanFocus ? arrowScrollFocused(direction) : null; if (focusResult != null) { nextSelectedPosition = focusResult.getSelectedPosition(); amountToScroll = focusResult.getAmountToScroll(); } boolean needToRedraw = focusResult != null; if (nextSelectedPosition != INVALID_POSITION) { handleNewSelectionChange(selectedView, direction, nextSelectedPosition, focusResult != null); setSelectedPositionInt(nextSelectedPosition); setNextSelectedPositionInt(nextSelectedPosition); selectedView = getSelectedView(); selectedPos = nextSelectedPosition; if (mItemsCanFocus && focusResult == null) { // there was no new view found to take focus, make sure we // don't leave focus with the old selection final View focused = getFocusedChild(); if (focused != null) { focused.clearFocus(); } } needToRedraw = true; checkSelectionChanged(); } if (amountToScroll > 0) { scrollListItemsBy((direction == View.FOCUS_UP) ? amountToScroll : -amountToScroll); needToRedraw = true; } // if we didn't find a new focusable, make sure any existing focused // item that was panned off screen gives up focus. if (mItemsCanFocus && (focusResult == null) && selectedView != null && selectedView.hasFocus()) { final View focused = selectedView.findFocus(); if (!isViewAncestorOf(focused, this) || distanceToView(focused) > 0) { focused.clearFocus(); } } // if the current selection is panned off, we need to remove the selection if (nextSelectedPosition == INVALID_POSITION && selectedView != null && !isViewAncestorOf(selectedView, this)) { selectedView = null; hideSelector(); // but we don't want to set the ressurect position (that would make subsequent // unhandled key events bring back the item we just scrolled off!) mResurrectToPosition = INVALID_POSITION; } if (needToRedraw) { if (selectedView != null) { positionSelector(selectedPos, selectedView); mSelectedLeft = selectedView.getLeft(); } if (!awakenScrollBars()) { invalidate(); } invokeOnItemScrollListener(); return true; } return false; } /** * When selection changes, it is possible that the previously selected or the next selected item will change its size. If so, we * need to offset some folks, and re-layout the items as appropriate. * * @param selectedView The currently selected view (before changing selection). should be <code>null</code> if there was no previous * selection. * @param direction Either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @param newSelectedPosition The position of the next selection. * @param newFocusAssigned whether new focus was assigned. This matters because when something has focus, we don't want to show selection * (ugh). */ private void handleNewSelectionChange(View selectedView, int direction, int newSelectedPosition, boolean newFocusAssigned) { if (newSelectedPosition == INVALID_POSITION) { throw new IllegalArgumentException("newSelectedPosition needs to be valid"); } // whether or not we are moving down or up, we want to preserve the // top of whatever view is on top: // - moving down: the view that had selection // - moving up: the view that is getting selection View leftView; View rightView; int leftViewIndex, rightViewIndex; boolean leftSelected = false; final int selectedIndex = mSelectedPosition - mFirstPosition; final int nextSelectedIndex = newSelectedPosition - mFirstPosition; if (direction == View.FOCUS_UP) { leftViewIndex = nextSelectedIndex; rightViewIndex = selectedIndex; leftView = getChildAt(leftViewIndex); rightView = selectedView; leftSelected = true; } else { leftViewIndex = selectedIndex; rightViewIndex = nextSelectedIndex; leftView = selectedView; rightView = getChildAt(rightViewIndex); } final int numChildren = getChildCount(); // start with top view: is it changing size? if (leftView != null) { leftView.setSelected(!newFocusAssigned && leftSelected); measureAndAdjustRight(leftView, leftViewIndex, numChildren); } // is the bottom view changing size? if (rightView != null) { rightView.setSelected(!newFocusAssigned && !leftSelected); measureAndAdjustRight(rightView, rightViewIndex, numChildren); } } /** * Re-measure a child, and if its height changes, lay it out preserving its top, and adjust the children below it appropriately. * * @param child The child * @param childIndex The view group index of the child. * @param numChildren The number of children in the view group. */ private void measureAndAdjustRight(View child, int childIndex, int numChildren) { int oldWidth = child.getWidth(); measureItem(child); if (child.getMeasuredWidth() != oldWidth) { // lay out the view, preserving its top relayoutMeasuredItem(child); // adjust views below appropriately final int widthDelta = child.getMeasuredWidth() - oldWidth; for (int i = childIndex + 1; i < numChildren; i++) { getChildAt(i).offsetLeftAndRight(widthDelta); } } } /** * Measure a particular list child. TODO: unify with setUpChild. * * @param child The child. */ private void measureItem(View child) { ViewGroup.LayoutParams p = child.getLayoutParams(); if (p == null) { p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT); } int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec, mListPadding.top + mListPadding.bottom, p.height); int lpWidth = p.width; int childWidthSpec; if (lpWidth > 0) { childWidthSpec = MeasureSpec.makeMeasureSpec(lpWidth, MeasureSpec.EXACTLY); } else { childWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); } child.measure(childWidthSpec, childHeightSpec); } /** * Layout a child that has been measured, preserving its top position. TODO: unify with setUpChild. * * @param child The child. */ private void relayoutMeasuredItem(View child) { final int w = child.getMeasuredWidth(); final int h = child.getMeasuredHeight(); final int childTop = mListPadding.top; final int childBottom = childTop + h; final int childLeft = child.getLeft(); final int childRight = childLeft + w; child.layout(childLeft, childTop, childRight, childBottom); } /** * @return The amount to preview next items when arrow srolling. */ private int getArrowScrollPreviewLength() { return Math.max(MIN_SCROLL_PREVIEW_PIXELS, getHorizontalFadingEdgeLength()); } /** * Determine how much we need to scroll in order to get the next selected view visible, with a fading edge showing below as * applicable. The amount is capped at {@link #getMaxScrollAmount()} . * * @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @param nextSelectedPosition The position of the next selection, or {@link #INVALID_POSITION} if there is no next selectable position * @return The amount to scroll. Note: this is always positive! Direction needs to be taken into account when actually scrolling. */ private int amountToScroll(int direction, int nextSelectedPosition) { final int listRight = getWidth() - mListPadding.right; final int listLeft = mListPadding.left; final int numChildren = getChildCount(); if (direction == View.FOCUS_DOWN) { int indexToMakeVisible = numChildren - 1; if (nextSelectedPosition != INVALID_POSITION) { indexToMakeVisible = nextSelectedPosition - mFirstPosition; } final int positionToMakeVisible = mFirstPosition + indexToMakeVisible; final View viewToMakeVisible = getChildAt(indexToMakeVisible); int goalRight = listRight; if (positionToMakeVisible < mItemCount - 1) { goalRight -= getArrowScrollPreviewLength(); } if (viewToMakeVisible.getRight() <= goalRight) { // item is fully visible. return 0; } if (nextSelectedPosition != INVALID_POSITION && (goalRight - viewToMakeVisible.getLeft()) >= getMaxScrollAmount()) { // item already has enough of it visible, changing selection is good enough return 0; } int amountToScroll = (viewToMakeVisible.getRight() - goalRight); if ((mFirstPosition + numChildren) == mItemCount) { // last is last in list -> make sure we don't scroll past it final int max = getChildAt(numChildren - 1).getRight() - listRight; amountToScroll = Math.min(amountToScroll, max); } return Math.min(amountToScroll, getMaxScrollAmount()); } else { int indexToMakeVisible = 0; if (nextSelectedPosition != INVALID_POSITION) { indexToMakeVisible = nextSelectedPosition - mFirstPosition; } final int positionToMakeVisible = mFirstPosition + indexToMakeVisible; final View viewToMakeVisible = getChildAt(indexToMakeVisible); int goalLeft = listLeft; if (positionToMakeVisible > 0) { goalLeft += getArrowScrollPreviewLength(); } if (viewToMakeVisible.getLeft() >= goalLeft) { // item is fully visible. return 0; } if (nextSelectedPosition != INVALID_POSITION && (viewToMakeVisible.getRight() - goalLeft) >= getMaxScrollAmount()) { // item already has enough of it visible, changing selection is good enough return 0; } int amountToScroll = (goalLeft - viewToMakeVisible.getLeft()); if (mFirstPosition == 0) { // first is first in list -> make sure we don't scroll past it final int max = listLeft - getChildAt(0).getLeft(); amountToScroll = Math.min(amountToScroll, max); } return Math.min(amountToScroll, getMaxScrollAmount()); } } /** * Holds results of focus aware arrow scrolling. */ static private class ArrowScrollFocusResult { private int mSelectedPosition; private int mAmountToScroll; /** * How {@link it.sephiroth.android.library.widget.HListView#arrowScrollFocused} returns its values. */ void populate(int selectedPosition, int amountToScroll) { mSelectedPosition = selectedPosition; mAmountToScroll = amountToScroll; } public int getSelectedPosition() { return mSelectedPosition; } public int getAmountToScroll() { return mAmountToScroll; } } /** * @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @return The position of the next selectable position of the views that are currently visible, taking into account the fact * that there might be no selection. Returns {@link #INVALID_POSITION} if there is no selectable view on screen in the * given direction. */ private int lookForSelectablePositionOnScreen(int direction) { final int firstPosition = mFirstPosition; if (direction == View.FOCUS_DOWN) { int startPos = (mSelectedPosition != INVALID_POSITION) ? mSelectedPosition + 1 : firstPosition; if (startPos >= mAdapter.getCount()) { return INVALID_POSITION; } if (startPos < firstPosition) { startPos = firstPosition; } final int lastVisiblePos = getLastVisiblePosition(); final ListAdapter adapter = getAdapter(); for (int pos = startPos; pos <= lastVisiblePos; pos++) { if (adapter.isEnabled(pos) && getChildAt(pos - firstPosition).getVisibility() == View.VISIBLE) { return pos; } } } else { int last = firstPosition + getChildCount() - 1; int startPos = (mSelectedPosition != INVALID_POSITION) ? mSelectedPosition - 1 : firstPosition + getChildCount() - 1; if (startPos < 0 || startPos >= mAdapter.getCount()) { return INVALID_POSITION; } if (startPos > last) { startPos = last; } final ListAdapter adapter = getAdapter(); for (int pos = startPos; pos >= firstPosition; pos--) { if (adapter.isEnabled(pos) && getChildAt(pos - firstPosition).getVisibility() == View.VISIBLE) { return pos; } } } return INVALID_POSITION; } /** * Do an arrow scroll based on focus searching. If a new view is given focus, return the selection delta and amount to scroll via * an {@link ArrowScrollFocusResult}, otherwise, return null. * * @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @return The result if focus has changed, or <code>null</code>. */ private ArrowScrollFocusResult arrowScrollFocused(final int direction) { final View selectedView = getSelectedView(); View newFocus; if (selectedView != null && selectedView.hasFocus()) { View oldFocus = selectedView.findFocus(); newFocus = FocusFinder.getInstance().findNextFocus(this, oldFocus, direction); } else { if (direction == View.FOCUS_DOWN) { final boolean leftFadingEdgeShowing = (mFirstPosition > 0); final int listLeft = mListPadding.left + (leftFadingEdgeShowing ? getArrowScrollPreviewLength() : 0); final int xSearchPoint = (selectedView != null && selectedView.getLeft() > listLeft) ? selectedView.getLeft() : listLeft; mTempRect.set(xSearchPoint, 0, xSearchPoint, 0); } else { final boolean rightFadingEdgeShowing = (mFirstPosition + getChildCount() - 1) < mItemCount; final int listRight = getWidth() - mListPadding.right - (rightFadingEdgeShowing ? getArrowScrollPreviewLength() : 0); final int xSearchPoint = (selectedView != null && selectedView.getRight() < listRight) ? selectedView.getRight() : listRight; mTempRect.set(xSearchPoint, 0, xSearchPoint, 0); } newFocus = FocusFinder.getInstance().findNextFocusFromRect(this, mTempRect, direction); } if (newFocus != null) { final int positionOfNewFocus = positionOfNewFocus(newFocus); // if the focus change is in a different new position, make sure // we aren't jumping over another selectable position if (mSelectedPosition != INVALID_POSITION && positionOfNewFocus != mSelectedPosition) { final int selectablePosition = lookForSelectablePositionOnScreen(direction); if (selectablePosition != INVALID_POSITION && ((direction == View.FOCUS_DOWN && selectablePosition < positionOfNewFocus) || (direction == View.FOCUS_UP && selectablePosition > positionOfNewFocus))) { return null; } } int focusScroll = amountToScrollToNewFocus(direction, newFocus, positionOfNewFocus); final int maxScrollAmount = getMaxScrollAmount(); if (focusScroll < maxScrollAmount) { // not moving too far, safe to give next view focus newFocus.requestFocus(direction); mArrowScrollFocusResult.populate(positionOfNewFocus, focusScroll); return mArrowScrollFocusResult; } else if (distanceToView(newFocus) < maxScrollAmount) { // Case to consider: // too far to get entire next focusable on screen, but by going // max scroll amount, we are getting it at least partially in view, // so give it focus and scroll the max ammount. newFocus.requestFocus(direction); mArrowScrollFocusResult.populate(positionOfNewFocus, maxScrollAmount); return mArrowScrollFocusResult; } } return null; } /** * @param newFocus The view that would have focus. * @return the position that contains newFocus */ private int positionOfNewFocus(View newFocus) { final int numChildren = getChildCount(); for (int i = 0; i < numChildren; i++) { final View child = getChildAt(i); if (isViewAncestorOf(newFocus, child)) { return mFirstPosition + i; } } throw new IllegalArgumentException("newFocus is not a child of any of the" + " children of the list!"); } /** * Return true if child is an ancestor of parent, (or equal to the parent). */ private boolean isViewAncestorOf(View child, View parent) { if (child == parent) { return true; } final ViewParent theParent = child.getParent(); return (theParent instanceof ViewGroup) && isViewAncestorOf((View) theParent, parent); } /** * Determine how much we need to scroll in order to get newFocus in view. * * @param direction either {@link android.view.View#FOCUS_UP} or {@link android.view.View#FOCUS_DOWN}. * @param newFocus The view that would take focus. * @param positionOfNewFocus The position of the list item containing newFocus * @return The amount to scroll. Note: this is always positive! Direction needs to be taken into account when actually scrolling. */ private int amountToScrollToNewFocus(int direction, View newFocus, int positionOfNewFocus) { int amountToScroll = 0; newFocus.getDrawingRect(mTempRect); offsetDescendantRectToMyCoords(newFocus, mTempRect); if (direction == View.FOCUS_UP) { if (mTempRect.left < mListPadding.left) { amountToScroll = mListPadding.left - mTempRect.left; if (positionOfNewFocus > 0) { amountToScroll += getArrowScrollPreviewLength(); } } } else { final int listRight = getWidth() - mListPadding.right; if (mTempRect.bottom > listRight) { amountToScroll = mTempRect.right - listRight; if (positionOfNewFocus < mItemCount - 1) { amountToScroll += getArrowScrollPreviewLength(); } } } return amountToScroll; } /** * Determine the distance to the nearest edge of a view in a particular direction. * * @param descendant A descendant of this list. * @return The distance, or 0 if the nearest edge is already on screen. */ private int distanceToView(View descendant) { int distance = 0; descendant.getDrawingRect(mTempRect); offsetDescendantRectToMyCoords(descendant, mTempRect); final int listRight = getRight() - getLeft() - mListPadding.right; if (mTempRect.right < mListPadding.left) { distance = mListPadding.left - mTempRect.right; } else if (mTempRect.left > listRight) { distance = mTempRect.left - listRight; } return distance; } /** * Scroll the children by amount, adding a view at the end and removing views that fall off as necessary. * * @param amount The amount (positive or negative) to scroll. */ private void scrollListItemsBy(int amount) { offsetChildrenLeftAndRight(amount); final int listRight = getWidth() - mListPadding.right; final int listLeft = mListPadding.left; final AbsHListView.RecycleBin recycleBin = mRecycler; if (amount < 0) { // shifted items up // may need to pan views into the bottom space int numChildren = getChildCount(); View last = getChildAt(numChildren - 1); while (last.getRight() < listRight) { final int lastVisiblePosition = mFirstPosition + numChildren - 1; if (lastVisiblePosition < mItemCount - 1) { last = addViewAfter(last, lastVisiblePosition); numChildren++; } else { break; } } // may have brought in the last child of the list that is skinnier // than the fading edge, thereby leaving space at the end. need // to shift back if (last.getBottom() < listRight) { offsetChildrenLeftAndRight(listRight - last.getRight()); } // top views may be panned off screen View first = getChildAt(0); while (first.getRight() < listLeft) { AbsHListView.LayoutParams layoutParams = (LayoutParams) first.getLayoutParams(); if (recycleBin.shouldRecycleViewType(layoutParams.viewType)) { detachViewFromParent(first); recycleBin.addScrapView(first, mFirstPosition); } else { removeViewInLayout(first); } first = getChildAt(0); mFirstPosition++; } } else { // shifted items down View first = getChildAt(0); // may need to pan views into top while ((first.getLeft() > listLeft) && (mFirstPosition > 0)) { first = addViewBefore(first, mFirstPosition); mFirstPosition--; } // may have brought the very first child of the list in too far and // need to shift it back if (first.getLeft() > listLeft) { offsetChildrenLeftAndRight(listLeft - first.getLeft()); } int lastIndex = getChildCount() - 1; View last = getChildAt(lastIndex); // bottom view may be panned off screen while (last.getLeft() > listRight) { AbsHListView.LayoutParams layoutParams = (LayoutParams) last.getLayoutParams(); if (recycleBin.shouldRecycleViewType(layoutParams.viewType)) { detachViewFromParent(last); recycleBin.addScrapView(last, mFirstPosition + lastIndex); } else { removeViewInLayout(last); } last = getChildAt(--lastIndex); } } } private View addViewBefore(View theView, int position) { int abovePosition = position - 1; View view = obtainView(abovePosition, mIsScrap); int edgeOfNewChild = theView.getLeft() - mDividerWidth; setupChild(view, abovePosition, edgeOfNewChild, false, mListPadding.top, false, mIsScrap[0]); return view; } private View addViewAfter(View theView, int position) { int belowPosition = position + 1; View view = obtainView(belowPosition, mIsScrap); int edgeOfNewChild = theView.getRight() + mDividerWidth; setupChild(view, belowPosition, edgeOfNewChild, true, mListPadding.top, false, mIsScrap[0]); return view; } /** * Indicates that the views created by the ListAdapter can contain focusable items. * * @param itemsCanFocus true if items can get focus, false otherwise */ public void setItemsCanFocus(boolean itemsCanFocus) { mItemsCanFocus = itemsCanFocus; if (!itemsCanFocus) { setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS); } } /** * @return Whether the views created by the ListAdapter can contain focusable items. */ public boolean getItemsCanFocus() { return mItemsCanFocus; } @Override public boolean isOpaque() { boolean retValue = (mCachingActive && mIsCacheColorOpaque && mDividerIsOpaque) || super.isOpaque(); if (retValue) { // only return true if the list items cover the entire area of the view final int listLeft = mListPadding != null ? mListPadding.left : getPaddingLeft(); View first = getChildAt(0); if (first == null || first.getLeft() > listLeft) { return false; } final int listRight = getWidth() - (mListPadding != null ? mListPadding.right : getPaddingRight()); View last = getChildAt(getChildCount() - 1); if (last == null || last.getRight() < listRight) { return false; } } return retValue; } @Override public void setCacheColorHint(int color) { final boolean opaque = (color >>> 24) == 0xFF; mIsCacheColorOpaque = opaque; if (opaque) { if (mDividerPaint == null) { mDividerPaint = new Paint(); } mDividerPaint.setColor(color); } super.setCacheColorHint(color); } void drawOverscrollHeader(Canvas canvas, Drawable drawable, Rect bounds) { final int width = drawable.getMinimumWidth(); canvas.save(); canvas.clipRect(bounds); final int span = bounds.right - bounds.left; if (span < width) { bounds.left = bounds.right - width; } drawable.setBounds(bounds); drawable.draw(canvas); canvas.restore(); } void drawOverscrollFooter(Canvas canvas, Drawable drawable, Rect bounds) { final int width = drawable.getMinimumWidth(); canvas.save(); canvas.clipRect(bounds); final int span = bounds.right - bounds.left; if (span < width) { bounds.right = bounds.left + width; } drawable.setBounds(bounds); drawable.draw(canvas); canvas.restore(); } @Override protected void dispatchDraw(Canvas canvas) { if (mCachingStarted) { mCachingActive = true; } // Draw the dividers final int dividerWidth = mDividerWidth; final Drawable overscrollHeader = mOverScrollHeader; final Drawable overscrollFooter = mOverScrollFooter; final boolean drawOverscrollHeader = overscrollHeader != null; final boolean drawOverscrollFooter = overscrollFooter != null; final boolean drawDividers = dividerWidth > 0 && mDivider != null; if (drawDividers || drawOverscrollHeader || drawOverscrollFooter) { // Only modify the top and bottom in the loop, we set the left and right here final Rect bounds = mTempRect; bounds.top = getPaddingTop(); bounds.bottom = getBottom() - getTop() - getPaddingBottom(); final int count = getChildCount(); final int headerCount = mHeaderViewInfos.size(); final int itemCount = mItemCount; final int footerLimit = itemCount - mFooterViewInfos.size() - 1; final boolean headerDividers = mHeaderDividersEnabled; final boolean footerDividers = mFooterDividersEnabled; final int first = mFirstPosition; final boolean areAllItemsSelectable = mAreAllItemsSelectable; final ListAdapter adapter = mAdapter; // If the list is opaque *and* the background is not, we want to // fill a rect where the dividers would be for non-selectable items // If the list is opaque and the background is also opaque, we don't // need to draw anything since the background will do it for us final boolean fillForMissingDividers = isOpaque() && !super.isOpaque(); if (fillForMissingDividers && mDividerPaint == null && mIsCacheColorOpaque) { mDividerPaint = new Paint(); mDividerPaint.setColor(getCacheColorHint()); } final Paint paint = mDividerPaint; int effectivePaddingLeft = 0; int effectivePaddingRight = 0; // if ( ( mGroupFlags & CLIP_TO_PADDING_MASK ) == CLIP_TO_PADDING_MASK ) { // effectivePaddingTop = mListPadding.top; // effectivePaddingBottom = mListPadding.bottom; // } final int listRight = getRight() - getLeft() - effectivePaddingRight + getScrollX(); if (!mStackFromRight) { int right = 0; // Draw top divider or header for overscroll final int scrollX = getScrollX(); if (count > 0 && scrollX < 0) { if (drawOverscrollHeader) { bounds.right = 0; bounds.left = scrollX; drawOverscrollHeader(canvas, overscrollHeader, bounds); } else if (drawDividers) { bounds.right = 0; bounds.left = -dividerWidth; drawDivider(canvas, bounds, -1); } } for (int i = 0; i < count; i++) { if ((headerDividers || first + i >= headerCount) && (footerDividers || first + i < footerLimit)) { View child = getChildAt(i); right = child.getRight(); // Don't draw dividers next to items that are not enabled if (drawDividers && (right < listRight && !(drawOverscrollFooter && i == count - 1))) { if ((areAllItemsSelectable || (adapter.isEnabled(first + i) && (i == count - 1 || adapter.isEnabled(first + i + 1))))) { bounds.left = right; bounds.right = right + dividerWidth; drawDivider(canvas, bounds, i); } else if (fillForMissingDividers) { bounds.left = right; bounds.right = right + dividerWidth; canvas.drawRect(bounds, paint); } } } } final int overFooterBottom = getRight() + getScrollX(); if (drawOverscrollFooter && first + count == itemCount && overFooterBottom > right) { bounds.left = right; bounds.right = overFooterBottom; drawOverscrollFooter(canvas, overscrollFooter, bounds); } } else { int left; final int scrollX = getScrollX(); if (count > 0 && drawOverscrollHeader) { bounds.left = scrollX; bounds.right = getChildAt(0).getLeft(); drawOverscrollHeader(canvas, overscrollHeader, bounds); } final int start = drawOverscrollHeader ? 1 : 0; for (int i = start; i < count; i++) { if ((headerDividers || first + i >= headerCount) && (footerDividers || first + i < footerLimit)) { View child = getChildAt(i); left = child.getLeft(); // Don't draw dividers next to items that are not enabled if (left > effectivePaddingLeft) { if ((areAllItemsSelectable || (adapter.isEnabled(first + i) && (i == count - 1 || adapter.isEnabled(first + i + 1))))) { bounds.left = left - dividerWidth; bounds.right = left; // Give the method the child ABOVE the divider, so we // subtract one from our child // position. Give -1 when there is no child above the // divider. drawDivider(canvas, bounds, i - 1); } else if (fillForMissingDividers) { bounds.left = left - dividerWidth; bounds.right = left; canvas.drawRect(bounds, paint); } } } } if (count > 0 && scrollX > 0) { if (drawOverscrollFooter) { final int absListRight = getRight(); bounds.left = absListRight; bounds.right = absListRight + scrollX; drawOverscrollFooter(canvas, overscrollFooter, bounds); } else if (drawDividers) { bounds.left = listRight; bounds.right = listRight + dividerWidth; drawDivider(canvas, bounds, -1); } } } } // Draw the indicators (these should be drawn above the dividers) and children super.dispatchDraw(canvas); } @Override protected boolean drawChild(Canvas canvas, View child, long drawingTime) { boolean more = super.drawChild(canvas, child, drawingTime); if (mCachingActive /* && child.mCachingFailed */) { mCachingActive = false; } return more; } /** * Draws a divider for the given child in the given bounds. * * @param canvas The canvas to draw to. * @param bounds The bounds of the divider. * @param childIndex The index of child (of the View) above the divider. This will be -1 if there is no child above the divider to be * drawn. */ void drawDivider(Canvas canvas, Rect bounds, int childIndex) { // This widget draws the same divider for all children final Drawable divider = mDivider; divider.setBounds(bounds); divider.draw(canvas); } /** * Returns the drawable that will be drawn between each item in the list. * * @return the current drawable drawn between list elements */ public Drawable getDivider() { return mDivider; } /** * Sets the drawable that will be drawn between each item in the list. If the drawable does not have an intrinsic height, you * should also call {@link #setDividerHeight(int)} * * @param divider The drawable to use. */ public void setDivider(Drawable divider) { if (LOG_ENABLED) { Log.i(LOG_TAG, "setDivider: " + divider); } if (divider != null) { mDividerWidth = divider.getIntrinsicWidth(); } else { mDividerWidth = 0; } mDivider = divider; mDividerIsOpaque = divider == null || divider.getOpacity() == PixelFormat.OPAQUE; requestLayout(); invalidate(); } /** * @return Returns the height of the divider that will be drawn between each item in the list. */ public int getDividerWidth() { return mDividerWidth; } /** * Sets the height of the divider that will be drawn between each item in the list. Calling this will override the intrinsic * height as set by {@link #setDivider(Drawable)} * * @param height The new height of the divider in pixels. */ public void setDividerWidth(int width) { if (LOG_ENABLED) { Log.i(LOG_TAG, "setDividerWidth: " + width); } mDividerWidth = width; requestLayout(); invalidate(); } /** * Enables or disables the drawing of the divider for header views. * * @param headerDividersEnabled True to draw the headers, false otherwise. * @see #setFooterDividersEnabled(boolean) * @see #addHeaderView(android.view.View) */ public void setHeaderDividersEnabled(boolean headerDividersEnabled) { mHeaderDividersEnabled = headerDividersEnabled; invalidate(); } /** * Enables or disables the drawing of the divider for footer views. * * @param footerDividersEnabled True to draw the footers, false otherwise. * @see #setHeaderDividersEnabled(boolean) * @see #addFooterView(android.view.View) */ public void setFooterDividersEnabled(boolean footerDividersEnabled) { mFooterDividersEnabled = footerDividersEnabled; invalidate(); } /** * Sets the drawable that will be drawn above all other list content. This area can become visible when the user overscrolls the * list. * * @param header The drawable to use */ public void setOverscrollHeader(Drawable header) { mOverScrollHeader = header; if (getScrollX() < 0) { invalidate(); } } /** * @return The drawable that will be drawn above all other list content */ public Drawable getOverscrollHeader() { return mOverScrollHeader; } /** * Sets the drawable that will be drawn below all other list content. This area can become visible when the user overscrolls the * list, or when the list's content does not fully fill the container area. * * @param footer The drawable to use */ public void setOverscrollFooter(Drawable footer) { mOverScrollFooter = footer; invalidate(); } /** * @return The drawable that will be drawn below all other list content */ public Drawable getOverscrollFooter() { return mOverScrollFooter; } @Override protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); final ListAdapter adapter = mAdapter; int closetChildIndex = -1; int closestChildLeft = 0; if (adapter != null && gainFocus && previouslyFocusedRect != null) { previouslyFocusedRect.offset(getScrollX(), getScrollY()); // Don't cache the result of getChildCount or mFirstPosition here, // it could change in layoutChildren. if (adapter.getCount() < getChildCount() + mFirstPosition) { mLayoutMode = LAYOUT_NORMAL; layoutChildren(); } // figure out which item should be selected based on previously // focused rect Rect otherRect = mTempRect; int minDistance = Integer.MAX_VALUE; final int childCount = getChildCount(); final int firstPosition = mFirstPosition; for (int i = 0; i < childCount; i++) { // only consider selectable views if (!adapter.isEnabled(firstPosition + i)) { continue; } View other = getChildAt(i); other.getDrawingRect(otherRect); offsetDescendantRectToMyCoords(other, otherRect); int distance = getDistance(previouslyFocusedRect, otherRect, direction); if (distance < minDistance) { minDistance = distance; closetChildIndex = i; closestChildLeft = other.getLeft(); } } } if (closetChildIndex >= 0) { setSelectionFromLeft(closetChildIndex + mFirstPosition, closestChildLeft); } else { requestLayout(); } } /* * (non-Javadoc) * * Children specified in XML are assumed to be header views. After we have parsed them move them out of the children list and * into mHeaderViews. */ @Override protected void onFinishInflate() { super.onFinishInflate(); int count = getChildCount(); if (count > 0) { for (int i = 0; i < count; ++i) { addHeaderView(getChildAt(i)); } removeAllViews(); } } /* * @Override protected View findViewByPredicateTraversal( Predicate<View> predicate, View childToSkip ) { View v; v = * super.findViewByPredicateTraversal( predicate, childToSkip ); if ( v == null ) { v = findViewByPredicateInHeadersOrFooters( * mHeaderViewInfos, predicate, childToSkip ); if ( v != null ) { return v; } * * v = findViewByPredicateInHeadersOrFooters( mFooterViewInfos, predicate, childToSkip ); if ( v != null ) { return v; } } return * v; } */ /* * View findViewByPredicateInHeadersOrFooters( ArrayList<FixedViewInfo> where, Predicate<View> predicate, View childToSkip ) { if * ( where != null ) { int len = where.size(); View v; * * for ( int i = 0; i < len; i++ ) { v = where.get( i ).view; * * if ( v != childToSkip && !v.isRootNamespace() ) { v = v.findViewByPredicate( predicate ); * * if ( v != null ) { return v; } } } } return null; } */ /** * Returns the set of checked items ids. The result is only valid if the choice mode has not been set to * {@link #CHOICE_MODE_NONE}. * * @return A new array which contains the id of each checked item in the list. * @deprecated Use {@link #getCheckedItemIds()} instead. */ @Deprecated public long[] getCheckItemIds() { // Use new behavior that correctly handles stable ID mapping. if (mAdapter != null && mAdapter.hasStableIds()) { return getCheckedItemIds(); } // Old behavior was buggy, but would sort of work for adapters without stable IDs. // Fall back to it to support legacy apps. if (mChoiceMode != ListView.CHOICE_MODE_NONE && mCheckStates != null && mAdapter != null) { final SparseArrayCompat<Boolean> states = mCheckStates; final int count = states.size(); final long[] ids = new long[count]; final ListAdapter adapter = mAdapter; int checkedCount = 0; for (int i = 0; i < count; i++) { if (states.valueAt(i)) { ids[checkedCount++] = adapter.getItemId(states.keyAt(i)); } } // Trim array if needed. mCheckStates may contain false values // resulting in checkedCount being smaller than count. if (checkedCount == count) { return ids; } else { final long[] result = new long[checkedCount]; System.arraycopy(ids, 0, result, 0, checkedCount); return result; } } return new long[0]; } @Override public void onInitializeAccessibilityEvent(AccessibilityEvent event) { super.onInitializeAccessibilityEvent(event); event.setClassName(HListView.class.getName()); } @TargetApi(14) @Override public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { super.onInitializeAccessibilityNodeInfo(info); info.setClassName(HListView.class.getName()); } @Override public void onGlobalLayout() { } }