Java tutorial
/* * Copyright (C) 2015 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.android.mylauncher3.allapps; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.content.pm.ResolveInfo; import android.content.res.Resources; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.PointF; import android.graphics.Rect; import android.support.v4.view.accessibility.AccessibilityRecordCompat; import android.support.v4.view.accessibility.AccessibilityEventCompat; import android.net.Uri; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.view.accessibility.AccessibilityEvent; import android.widget.TextView; import com.android.mylauncher3.AppInfo; import com.android.mylauncher3.BubbleTextView; import com.android.mylauncher3.Launcher; import com.android.mylauncher3.R; import com.android.mylauncher3.Utilities; import com.android.mylauncher3.util.Thunk; import java.util.HashMap; import java.util.List; /** * The grid view adapter of all the apps. */ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.ViewHolder> { public static final String TAG = "AppsGridAdapter"; private static final boolean DEBUG = false; // A section break in the grid public static final int SECTION_BREAK_VIEW_TYPE = 0; // A normal icon public static final int ICON_VIEW_TYPE = 1; // A prediction icon public static final int PREDICTION_ICON_VIEW_TYPE = 2; // The message shown when there are no filtered results public static final int EMPTY_SEARCH_VIEW_TYPE = 3; // A divider that separates the apps list and the search market button public static final int SEARCH_MARKET_DIVIDER_VIEW_TYPE = 4; // The message to continue to a market search when there are no filtered results public static final int SEARCH_MARKET_VIEW_TYPE = 5; /** * ViewHolder for each icon. */ public static class ViewHolder extends RecyclerView.ViewHolder { public View mContent; public ViewHolder(View v) { super(v); mContent = v; } } /** * A subclass of GridLayoutManager that overrides accessibility values during app search. */ public class AppsGridLayoutManager extends GridLayoutManager { public AppsGridLayoutManager(Context context) { super(context, 1, GridLayoutManager.VERTICAL, false); } @Override public void onInitializeAccessibilityEvent(AccessibilityEvent event) { super.onInitializeAccessibilityEvent(event); // Ensure that we only report the number apps for accessibility not including other // adapter views final AccessibilityRecordCompat record = AccessibilityEventCompat.asRecord(event); record.setItemCount(mApps.getNumFilteredApps()); } @Override public int getRowCountForAccessibility(RecyclerView.Recycler recycler, RecyclerView.State state) { if (mApps.hasNoFilteredResults()) { // Disregard the no-search-results text as a list item for accessibility return 0; } else { return super.getRowCountForAccessibility(recycler, state); } } } /** * Helper class to size the grid items. */ public class GridSpanSizer extends GridLayoutManager.SpanSizeLookup { public GridSpanSizer() { super(); setSpanIndexCacheEnabled(true); } @Override public int getSpanSize(int position) { switch (mApps.getAdapterItems().get(position).viewType) { case AllAppsGridAdapter.ICON_VIEW_TYPE: case AllAppsGridAdapter.PREDICTION_ICON_VIEW_TYPE: return 1; default: // Section breaks span the full width return mAppsPerRow; } } } /** * Helper class to draw the section headers */ public class GridItemDecoration extends RecyclerView.ItemDecoration { private static final boolean DEBUG_SECTION_MARGIN = false; private static final boolean FADE_OUT_SECTIONS = false; private HashMap<String, PointF> mCachedSectionBounds = new HashMap<>(); private Rect mTmpBounds = new Rect(); @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { if (mApps.hasFilter() || mAppsPerRow == 0) { return; } if (DEBUG_SECTION_MARGIN) { Paint p = new Paint(); p.setColor(0x33ff0000); c.drawRect(mBackgroundPadding.left, 0, mBackgroundPadding.left + mSectionNamesMargin, parent.getMeasuredHeight(), p); } List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems(); boolean hasDrawnPredictedAppsDivider = false; boolean showSectionNames = mSectionNamesMargin > 0; int childCount = parent.getChildCount(); int lastSectionTop = 0; int lastSectionHeight = 0; for (int i = 0; i < childCount; i++) { View child = parent.getChildAt(i); ViewHolder holder = (ViewHolder) parent.getChildViewHolder(child); if (!isValidHolderAndChild(holder, child, items)) { continue; } if (shouldDrawItemDivider(holder, items) && !hasDrawnPredictedAppsDivider) { // Draw the divider under the predicted apps int top = child.getTop() + child.getHeight() + mPredictionBarDividerOffset; c.drawLine(mBackgroundPadding.left, top, parent.getWidth() - mBackgroundPadding.right, top, mPredictedAppsDividerPaint); hasDrawnPredictedAppsDivider = true; } else if (showSectionNames && shouldDrawItemSection(holder, i, items)) { // At this point, we only draw sections for each section break; int viewTopOffset = (2 * child.getPaddingTop()); int pos = holder.getPosition(); AlphabeticalAppsList.AdapterItem item = items.get(pos); AlphabeticalAppsList.SectionInfo sectionInfo = item.sectionInfo; // Draw all the sections for this index String lastSectionName = item.sectionName; for (int j = item.sectionAppIndex; j < sectionInfo.numApps; j++, pos++) { AlphabeticalAppsList.AdapterItem nextItem = items.get(pos); String sectionName = nextItem.sectionName; if (nextItem.sectionInfo != sectionInfo) { break; } if (j > item.sectionAppIndex && sectionName.equals(lastSectionName)) { continue; } // Find the section name bounds PointF sectionBounds = getAndCacheSectionBounds(sectionName); // Calculate where to draw the section int sectionBaseline = (int) (viewTopOffset + sectionBounds.y); int x = mIsRtl ? parent.getWidth() - mBackgroundPadding.left - mSectionNamesMargin : mBackgroundPadding.left; x += (int) ((mSectionNamesMargin - sectionBounds.x) / 2f); int y = child.getTop() + sectionBaseline; // Determine whether this is the last row with apps in that section, if // so, then fix the section to the row allowing it to scroll past the // baseline, otherwise, bound it to the baseline so it's in the viewport int appIndexInSection = items.get(pos).sectionAppIndex; int nextRowPos = Math.min(items.size() - 1, pos + mAppsPerRow - (appIndexInSection % mAppsPerRow)); AlphabeticalAppsList.AdapterItem nextRowItem = items.get(nextRowPos); boolean fixedToRow = !sectionName.equals(nextRowItem.sectionName); if (!fixedToRow) { y = Math.max(sectionBaseline, y); } // In addition, if it overlaps with the last section that was drawn, then // offset it so that it does not overlap if (lastSectionHeight > 0 && y <= (lastSectionTop + lastSectionHeight)) { y += lastSectionTop - y + lastSectionHeight; } // Draw the section header if (FADE_OUT_SECTIONS) { int alpha = 255; if (fixedToRow) { alpha = Math.min(255, (int) (255 * (Math.max(0, y) / (float) sectionBaseline))); } mSectionTextPaint.setAlpha(alpha); } c.drawText(sectionName, x, y, mSectionTextPaint); lastSectionTop = y; lastSectionHeight = (int) (sectionBounds.y + mSectionHeaderOffset); lastSectionName = sectionName; } i += (sectionInfo.numApps - item.sectionAppIndex); } } } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { // Do nothing } /** * Given a section name, return the bounds of the given section name. */ private PointF getAndCacheSectionBounds(String sectionName) { PointF bounds = mCachedSectionBounds.get(sectionName); if (bounds == null) { mSectionTextPaint.getTextBounds(sectionName, 0, sectionName.length(), mTmpBounds); bounds = new PointF(mSectionTextPaint.measureText(sectionName), mTmpBounds.height()); mCachedSectionBounds.put(sectionName, bounds); } return bounds; } /** * Returns whether we consider this a valid view holder for us to draw a divider or section for. */ private boolean isValidHolderAndChild(ViewHolder holder, View child, List<AlphabeticalAppsList.AdapterItem> items) { // Ensure item is not already removed GridLayoutManager.LayoutParams lp = (GridLayoutManager.LayoutParams) child.getLayoutParams(); if (lp.isItemRemoved()) { return false; } // Ensure we have a valid holder if (holder == null) { return false; } // Ensure we have a holder position int pos = holder.getPosition(); if (pos < 0 || pos >= items.size()) { return false; } return true; } /** * Returns whether to draw the divider for a given child. */ private boolean shouldDrawItemDivider(ViewHolder holder, List<AlphabeticalAppsList.AdapterItem> items) { int pos = holder.getPosition(); return items.get(pos).viewType == AllAppsGridAdapter.PREDICTION_ICON_VIEW_TYPE; } /** * Returns whether to draw the section for the given child. */ private boolean shouldDrawItemSection(ViewHolder holder, int childIndex, List<AlphabeticalAppsList.AdapterItem> items) { int pos = holder.getPosition(); AlphabeticalAppsList.AdapterItem item = items.get(pos); // Ensure it's an icon if (item.viewType != AllAppsGridAdapter.ICON_VIEW_TYPE) { return false; } // Draw the section header for the first item in each section return (childIndex == 0) || (items.get(pos - 1).viewType == AllAppsGridAdapter.SECTION_BREAK_VIEW_TYPE); } } private Launcher mLauncher; private LayoutInflater mLayoutInflater; @Thunk AlphabeticalAppsList mApps; private GridLayoutManager mGridLayoutMgr; private GridSpanSizer mGridSizer; private GridItemDecoration mItemDecoration; private View.OnTouchListener mTouchListener; private View.OnClickListener mIconClickListener; private View.OnLongClickListener mIconLongClickListener; @Thunk final Rect mBackgroundPadding = new Rect(); @Thunk int mPredictionBarDividerOffset; @Thunk int mAppsPerRow; @Thunk boolean mIsRtl; // The text to show when there are no search results and no market search handler. private String mEmptySearchMessage; // The name of the market app which handles searches, to be used in the format str // below when updating the search-market view. Only needs to be loaded once. private String mMarketAppName; // The text to show when there is a market app which can handle a specific query, updated // each time the search query changes. private String mMarketSearchMessage; // The intent to send off to the market app, updated each time the search query changes. private Intent mMarketSearchIntent; // The last query that the user entered into the search field private String mLastSearchQuery; // Section drawing @Thunk int mSectionNamesMargin; @Thunk int mSectionHeaderOffset; @Thunk Paint mSectionTextPaint; @Thunk Paint mPredictedAppsDividerPaint; public AllAppsGridAdapter(Launcher launcher, AlphabeticalAppsList apps, View.OnTouchListener touchListener, View.OnClickListener iconClickListener, View.OnLongClickListener iconLongClickListener) { Resources res = launcher.getResources(); mLauncher = launcher; mApps = apps; mEmptySearchMessage = res.getString(R.string.all_apps_loading_message); mGridSizer = new GridSpanSizer(); mGridLayoutMgr = new AppsGridLayoutManager(launcher); mGridLayoutMgr.setSpanSizeLookup(mGridSizer); mItemDecoration = new GridItemDecoration(); mLayoutInflater = LayoutInflater.from(launcher); mTouchListener = touchListener; mIconClickListener = iconClickListener; mIconLongClickListener = iconLongClickListener; mSectionNamesMargin = res.getDimensionPixelSize(R.dimen.all_apps_grid_view_start_margin); mSectionHeaderOffset = res.getDimensionPixelSize(R.dimen.all_apps_grid_section_y_offset); mSectionTextPaint = new Paint(); mSectionTextPaint.setTextSize(res.getDimensionPixelSize(R.dimen.all_apps_grid_section_text_size)); mSectionTextPaint.setColor(res.getColor(R.color.all_apps_grid_section_text_color)); mSectionTextPaint.setAntiAlias(true); mPredictedAppsDividerPaint = new Paint(); mPredictedAppsDividerPaint.setStrokeWidth(Utilities.pxFromDp(1f, res.getDisplayMetrics())); mPredictedAppsDividerPaint.setColor(0x1E000000); mPredictedAppsDividerPaint.setAntiAlias(true); mPredictionBarDividerOffset = (-res.getDimensionPixelSize(R.dimen.all_apps_prediction_icon_bottom_padding) + res.getDimensionPixelSize(R.dimen.all_apps_icon_top_bottom_padding)) / 2; // Resolve the market app handling additional searches PackageManager pm = launcher.getPackageManager(); ResolveInfo marketInfo = pm.resolveActivity(createMarketSearchIntent(""), PackageManager.MATCH_DEFAULT_ONLY); if (marketInfo != null) { mMarketAppName = marketInfo.loadLabel(pm).toString(); } } /** * Sets the number of apps per row. */ public void setNumAppsPerRow(int appsPerRow) { mAppsPerRow = appsPerRow; mGridLayoutMgr.setSpanCount(appsPerRow); } /** * Sets whether we are in RTL mode. */ public void setRtl(boolean rtl) { mIsRtl = rtl; } /** * Sets the last search query that was made, used to show when there are no results and to also * seed the intent for searching the market. */ public void setLastSearchQuery(String query) { Resources res = mLauncher.getResources(); String formatStr = res.getString(R.string.all_apps_no_search_results); mLastSearchQuery = query; mEmptySearchMessage = String.format(formatStr, query); if (mMarketAppName != null) { mMarketSearchMessage = String.format(res.getString(R.string.all_apps_search_market_message), mMarketAppName); mMarketSearchIntent = createMarketSearchIntent(query); } } /** * Notifies the adapter of the background padding so that it can draw things correctly in the * item decorator. */ public void updateBackgroundPadding(Rect padding) { mBackgroundPadding.set(padding); } /** * Returns the grid layout manager. */ public GridLayoutManager getLayoutManager() { return mGridLayoutMgr; } /** * Returns the item decoration for the recycler view. */ public RecyclerView.ItemDecoration getItemDecoration() { // We don't draw any headers when we are uncomfortably dense return mItemDecoration; } @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { switch (viewType) { case SECTION_BREAK_VIEW_TYPE: return new ViewHolder(new View(parent.getContext())); case ICON_VIEW_TYPE: { BubbleTextView icon = (BubbleTextView) mLayoutInflater.inflate(R.layout.all_apps_icon, parent, false); icon.setOnTouchListener(mTouchListener); icon.setOnClickListener(mIconClickListener); icon.setOnLongClickListener(mIconLongClickListener); icon.setLongPressTimeout(ViewConfiguration.get(parent.getContext()).getLongPressTimeout()); icon.setFocusable(true); return new ViewHolder(icon); } case PREDICTION_ICON_VIEW_TYPE: { BubbleTextView icon = (BubbleTextView) mLayoutInflater.inflate(R.layout.all_apps_prediction_bar_icon, parent, false); icon.setOnTouchListener(mTouchListener); icon.setOnClickListener(mIconClickListener); icon.setOnLongClickListener(mIconLongClickListener); icon.setLongPressTimeout(ViewConfiguration.get(parent.getContext()).getLongPressTimeout()); icon.setFocusable(true); return new ViewHolder(icon); } case EMPTY_SEARCH_VIEW_TYPE: return new ViewHolder(mLayoutInflater.inflate(R.layout.all_apps_empty_search, parent, false)); case SEARCH_MARKET_DIVIDER_VIEW_TYPE: return new ViewHolder(mLayoutInflater.inflate(R.layout.all_apps_search_market_divider, parent, false)); case SEARCH_MARKET_VIEW_TYPE: View searchMarketView = mLayoutInflater.inflate(R.layout.all_apps_search_market, parent, false); searchMarketView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mLauncher.startSearchFromAllApps(v, mMarketSearchIntent, mLastSearchQuery); } }); return new ViewHolder(searchMarketView); default: throw new RuntimeException("Unexpected view type"); } } @Override public void onBindViewHolder(ViewHolder holder, int position) { switch (holder.getItemViewType()) { case ICON_VIEW_TYPE: { AppInfo info = mApps.getAdapterItems().get(position).appInfo; BubbleTextView icon = (BubbleTextView) holder.mContent; icon.applyFromApplicationInfo(info); break; } case PREDICTION_ICON_VIEW_TYPE: { AppInfo info = mApps.getAdapterItems().get(position).appInfo; BubbleTextView icon = (BubbleTextView) holder.mContent; icon.applyFromApplicationInfo(info); break; } case EMPTY_SEARCH_VIEW_TYPE: TextView emptyViewText = (TextView) holder.mContent; emptyViewText.setText(mEmptySearchMessage); emptyViewText.setGravity( mApps.hasNoFilteredResults() ? Gravity.CENTER : Gravity.START | Gravity.CENTER_VERTICAL); break; case SEARCH_MARKET_VIEW_TYPE: TextView searchView = (TextView) holder.mContent; if (mMarketSearchIntent != null) { searchView.setVisibility(View.VISIBLE); searchView.setContentDescription(mMarketSearchMessage); searchView.setGravity( mApps.hasNoFilteredResults() ? Gravity.CENTER : Gravity.START | Gravity.CENTER_VERTICAL); searchView.setText(mMarketSearchMessage); } else { searchView.setVisibility(View.GONE); } break; } } @Override public int getItemCount() { return mApps.getAdapterItems().size(); } @Override public int getItemViewType(int position) { AlphabeticalAppsList.AdapterItem item = mApps.getAdapterItems().get(position); return item.viewType; } /** * Creates a new market search intent. */ private Intent createMarketSearchIntent(String query) { Uri marketSearchUri = Uri.parse("market://search").buildUpon().appendQueryParameter("q", query).build(); Intent marketSearchIntent = new Intent(Intent.ACTION_VIEW); marketSearchIntent.setData(marketSearchUri); return marketSearchIntent; } }