Java tutorial
/* * 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.aboveware.actionbar.support; import android.os.Bundle; import android.os.Handler; import android.support.v4.app.Fragment; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnCreateContextMenuListener; import android.view.ViewGroup; import android.view.animation.AnimationUtils; import android.widget.AdapterView; import android.widget.ExpandableListView; import android.widget.FrameLayout; import android.widget.ListAdapter; import android.widget.ListView; import android.widget.TextView; import com.aboveware.actionbar.common.ExpandableListAdapter; import com.aboveware.actionbar.common.IExpandableListFragment; public abstract class ExpandableListFragmentSupport extends Fragment implements OnCreateContextMenuListener, ExpandableListView.OnChildClickListener, ExpandableListView.OnGroupCollapseListener, ExpandableListView.OnGroupExpandListener, AdapterView.OnItemLongClickListener, IExpandableListFragment { static final int INTERNAL_EMPTY_ID = 0x00ff0001; static final int INTERNAL_LIST_CONTAINER_ID = 0x00ff0003; final private Handler mHandler = new Handler(); final private Runnable mRequestFocus = new Runnable() { @Override public void run() { expandableListView.focusableViewAvailable(expandableListView); } }; final private AdapterView.OnItemClickListener mOnClickListener = new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View v, int position, long id) { onListItemClick((ListView) parent, v, position, id); } }; ExpandableListAdapter mAdapter; ExpandableListView expandableListView; View mEmptyView; TextView mStandardEmptyView; View mListContainer; boolean mSetEmptyText; boolean mListShown; boolean mFinishedStart = false; private long[] expandedIds; public ExpandableListFragmentSupport() { } protected boolean onListChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { // TODO Auto-generated method stub return false; } /** * Provide default implementation to return a simple list view. Subclasses can * override to replace with their own layout. If doing so, the returned view * hierarchy <em>must</em> have a ListView whose id is * {@link android.R.id#list android.R.id.list} and can optionally have a * sibling view id {@link android.R.id#empty android.R.id.empty} that is to be * shown when the list is empty. * <p/> * <p> * If you are overriding this method with your own custom content, consider * including the standard layout {@link android.R.layout#list_content} in your * layout file, so that you continue to retain all of the standard behavior of * ListFragment. In particular, this is currently the only way to have the * built-in indeterminant progress state be shown. */ @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { FrameLayout root = new FrameLayout(getActivity()); FrameLayout lframe = new FrameLayout(getActivity()); lframe.setId(INTERNAL_LIST_CONTAINER_ID); TextView tv = new TextView(getActivity()); tv.setId(INTERNAL_EMPTY_ID); tv.setGravity(Gravity.CENTER); lframe.addView(tv, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); ExpandableListView lv = new ExpandableListView(getActivity()); lv.setId(android.R.id.list); lv.setDrawSelectorOnTop(false); lframe.addView(lv, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); root.addView(lframe, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); ListView.LayoutParams lp = new ListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT); root.setLayoutParams(lp); return root; } @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2, long packedPosition) { int groupPosition = ExpandableListView.getPackedPositionGroup(packedPosition); int childPosition = ExpandableListView.getPackedPositionChild(packedPosition); return mAdapter.onItemLongClick(groupPosition, childPosition); } /** * Attach to list view once the view hierarchy has been created. */ @Override public void onViewCreated(View view, Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); ensureList(); if (savedInstanceState != null) { expandedIds = savedInstanceState.getLongArray(ExpandableListAdapter.EXPANDED_IDS); } } /* (non-Javadoc) * @see android.support.v4.app.Fragment#onStart() */ @Override public void onStart() { super.onStart(); mAdapter.onStart(expandedIds, expandableListView); } /* (non-Javadoc) * @see android.support.v4.app.Fragment#onStop() */ @Override public void onStop() { super.onStop(); mAdapter.onStop(expandableListView); } /* (non-Javadoc) * @see android.support.v4.app.Fragment#onSaveInstanceState(android.os.Bundle) */ @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); mAdapter.onSaveInstanceState(outState, expandableListView); } /** Detach from list view. */ @Override public void onDestroyView() { mHandler.removeCallbacks(mRequestFocus); expandableListView = null; super.onDestroyView(); } /** * This method will be called when an item in the list is selected. Subclasses * should override. Subclasses can call * getListView().getItemAtPosition(position) if they need to access the data * associated with the selected item. * * @param l * The ListView where the click happened * @param v * The view that was clicked within the ListView * @param position * The position of the view in the list * @param id * The row id of the item that was clicked */ public void onListItemClick(ListView l, View v, int position, long id) { } /** Provide the cursor for the list view. */ public void setListAdapter(ExpandableListAdapter adapter) { boolean hadAdapter = mAdapter != null; mAdapter = adapter; if (mAdapter != null) { mAdapter.setExpandableListFragment(this); } if (expandableListView != null) { expandableListView.setAdapter(adapter); if (!mListShown && !hadAdapter) { // The list was hidden, and previously didn't have an // adapter. It is now time to show it. setListShown(true, getView().getWindowToken() != null); } // SA - added this one! onContentChanged(); } } /** * Set the currently selected list item to the specified position with the * adapter's data */ @Override public void setSelection(int position) { ensureList(); expandableListView.setSelection(position); } public long getSelectedPosition() { ensureList(); return expandableListView.getSelectedPosition(); } public long getSelectedId() { ensureList(); return expandableListView.getSelectedId(); } public ExpandableListView getExpandableListView() { ensureList(); return expandableListView; } /** * The default content for a ListFragment has a TextView that can be shown * when the list is empty. If you would like to have it shown, call this * method to supply the text it should use. */ @Override public void setEmptyText(CharSequence text) { ensureList(); if (mStandardEmptyView == null) { throw new IllegalStateException("Can't be used with a custom content view"); } mStandardEmptyView.setText(text); if (!mSetEmptyText) { expandableListView.setEmptyView(mStandardEmptyView); mSetEmptyText = true; } } /** * Control whether the list is being displayed. You can make it not displayed * if you are waiting for the initial data to show in it. During this time an * indeterminant progress indicator will be shown instead. * <p/> * <p> * Applications do not normally need to use this themselves. The default * behavior of ListFragment is to start with the list not being shown, only * showing it once an adapter is given with * {@link #setListAdapter(ListAdapter)}. If the list at that point had not * been shown, when it does get shown it will be do without the user ever * seeing the hidden state. * * @param shown * If true, the list view is shown; if false, the progress indicator. * The initial value is true. */ public void setListShown(boolean shown) { setListShown(shown, true); } /** * Like {@link #setListShown(boolean)}, but no animation is used when * transitioning from the previous state. */ @Override public void setListShownNoAnimation(boolean shown) { setListShown(shown, false); } /** * Control whether the list is being displayed. You can make it not displayed * if you are waiting for the initial data to show in it. During this time an * indeterminant progress indicator will be shown instead. * * @param shown * If true, the list view is shown; if false, the progress indicator. * The initial value is true. * @param animate * If true, an animation will be used to transition to the new state. */ private void setListShown(boolean shown, boolean animate) { ensureList(); if (mListShown == shown) { return; } mListShown = shown; if (mListContainer != null) { if (shown) { if (animate) { mListContainer .startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_in)); } mListContainer.setVisibility(View.VISIBLE); } else { if (animate) { mListContainer .startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_out)); } mListContainer.setVisibility(View.GONE); } } } /** Get the ListAdapter associated with this activity's ListView. */ public ExpandableListAdapter getExpandableListAdapter() { return mAdapter; } private void ensureList() { if (expandableListView != null) { return; } View root = getView(); if (root == null) { throw new IllegalStateException("Content view not yet created"); } if (root instanceof ExpandableListView) { expandableListView = (ExpandableListView) root; } else { mStandardEmptyView = (TextView) root.findViewById(INTERNAL_EMPTY_ID); if (mStandardEmptyView == null) { mEmptyView = root.findViewById(android.R.id.empty); } mListContainer = root.findViewById(INTERNAL_LIST_CONTAINER_ID); View rawListView = root.findViewById(android.R.id.list); if (!(rawListView instanceof ExpandableListView)) { if (rawListView == null) { throw new RuntimeException("Your content must have a ExpandableListView whose id attribute is " + "'android.R.id.list'"); } throw new RuntimeException("Content has view with id attribute 'android.R.id.list' " + "that is not a ExpandableListView class"); } expandableListView = (ExpandableListView) rawListView; if (mEmptyView != null) { expandableListView.setEmptyView(mEmptyView); } } mListShown = true; expandableListView.setOnItemClickListener(mOnClickListener); if (mAdapter != null) { setListAdapter(mAdapter); } else { // We are starting without an adapter, so assume we won't // have our data right away and start with the progress indicator. setListShown(false, false); } mHandler.post(mRequestFocus); } @Override public void onGroupExpand(int arg0) { // TODO Auto-generated method stub } @Override public void onGroupCollapse(int arg0) { // TODO Auto-generated method stub } /** * Callback method to be invoked when a child in this expandable list has been * clicked. * * @param parent * The ExpandableListView where the click happened * @param v * The view within the expandable list/ListView that was clicked * @param groupPosition * The group position that contains the child that was clicked * @param childPosition * The child position within the group * @param id * he row id of the child that was clicked * @return True if the click was handled */ @Override public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { return mAdapter.onChildClick(parent, v, groupPosition, childPosition, id); } public void onContentChanged() { View emptyView = getView().findViewById(android.R.id.empty); expandableListView = (ExpandableListView) getView().findViewById(android.R.id.list); if (expandableListView == null) { throw new RuntimeException( "Your content must have a ExpandableListView whose id attribute is " + "'android.R.id.list'"); } if (emptyView != null) { expandableListView.setEmptyView(emptyView); } expandableListView.setOnChildClickListener(this); expandableListView.setOnGroupExpandListener(this); expandableListView.setOnGroupCollapseListener(this); expandableListView.setOnItemLongClickListener(this); if (mFinishedStart) { setListAdapter(mAdapter); } mFinishedStart = true; } @Override public void setSelectedGroup(int groupPosition) { ensureList(); expandableListView.setSelectedGroup(groupPosition); } @Override public void collapseGroup(int groupPosition) { ensureList(); expandableListView.collapseGroup(groupPosition); } abstract public void showDetails(int group, int index); }