• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2006 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.widget;
18 
19 import com.android.internal.R;
20 
21 import java.util.ArrayList;
22 
23 import android.content.Context;
24 import android.content.res.TypedArray;
25 import android.graphics.Canvas;
26 import android.graphics.Rect;
27 import android.graphics.drawable.Drawable;
28 import android.graphics.drawable.ColorDrawable;
29 import android.os.Parcel;
30 import android.os.Parcelable;
31 import android.util.AttributeSet;
32 import android.view.ContextMenu;
33 import android.view.SoundEffectConstants;
34 import android.view.View;
35 import android.view.ContextMenu.ContextMenuInfo;
36 import android.widget.AdapterView.AdapterContextMenuInfo;
37 import android.widget.ExpandableListConnector.PositionMetadata;
38 
39 /**
40  * A view that shows items in a vertically scrolling two-level list. This
41  * differs from the {@link ListView} by allowing two levels: groups which can
42  * individually be expanded to show its children. The items come from the
43  * {@link ExpandableListAdapter} associated with this view.
44  * <p>
45  * Expandable lists are able to show an indicator beside each item to display
46  * the item's current state (the states are usually one of expanded group,
47  * collapsed group, child, or last child). Use
48  * {@link #setChildIndicator(Drawable)} or {@link #setGroupIndicator(Drawable)}
49  * (or the corresponding XML attributes) to set these indicators (see the docs
50  * for each method to see additional state that each Drawable can have). The
51  * default style for an {@link ExpandableListView} provides indicators which
52  * will be shown next to Views given to the {@link ExpandableListView}. The
53  * layouts android.R.layout.simple_expandable_list_item_1 and
54  * android.R.layout.simple_expandable_list_item_2 (which should be used with
55  * {@link SimpleCursorTreeAdapter}) contain the preferred position information
56  * for indicators.
57  * <p>
58  * The context menu information set by an {@link ExpandableListView} will be a
59  * {@link ExpandableListContextMenuInfo} object with
60  * {@link ExpandableListContextMenuInfo#packedPosition} being a packed position
61  * that can be used with {@link #getPackedPositionType(long)} and the other
62  * similar methods.
63  * <p>
64  * <em><b>Note:</b></em> You cannot use the value <code>wrap_content</code>
65  * for the <code>android:layout_height</code> attribute of a
66  * ExpandableListView in XML if the parent's size is also not strictly specified
67  * (for example, if the parent were ScrollView you could not specify
68  * wrap_content since it also can be any length. However, you can use
69  * wrap_content if the ExpandableListView parent has a specific size, such as
70  * 100 pixels.
71  *
72  * @attr ref android.R.styleable#ExpandableListView_groupIndicator
73  * @attr ref android.R.styleable#ExpandableListView_indicatorLeft
74  * @attr ref android.R.styleable#ExpandableListView_indicatorRight
75  * @attr ref android.R.styleable#ExpandableListView_childIndicator
76  * @attr ref android.R.styleable#ExpandableListView_childIndicatorLeft
77  * @attr ref android.R.styleable#ExpandableListView_childIndicatorRight
78  * @attr ref android.R.styleable#ExpandableListView_childDivider
79  */
80 public class ExpandableListView extends ListView {
81 
82     /**
83      * The packed position represents a group.
84      */
85     public static final int PACKED_POSITION_TYPE_GROUP = 0;
86 
87     /**
88      * The packed position represents a child.
89      */
90     public static final int PACKED_POSITION_TYPE_CHILD = 1;
91 
92     /**
93      * The packed position represents a neither/null/no preference.
94      */
95     public static final int PACKED_POSITION_TYPE_NULL = 2;
96 
97     /**
98      * The value for a packed position that represents neither/null/no
99      * preference. This value is not otherwise possible since a group type
100      * (first bit 0) should not have a child position filled.
101      */
102     public static final long PACKED_POSITION_VALUE_NULL = 0x00000000FFFFFFFFL;
103 
104     /** The mask (in packed position representation) for the child */
105     private static final long PACKED_POSITION_MASK_CHILD = 0x00000000FFFFFFFFL;
106 
107     /** The mask (in packed position representation) for the group */
108     private static final long PACKED_POSITION_MASK_GROUP = 0x7FFFFFFF00000000L;
109 
110     /** The mask (in packed position representation) for the type */
111     private static final long PACKED_POSITION_MASK_TYPE  = 0x8000000000000000L;
112 
113     /** The shift amount (in packed position representation) for the group */
114     private static final long PACKED_POSITION_SHIFT_GROUP = 32;
115 
116     /** The shift amount (in packed position representation) for the type */
117     private static final long PACKED_POSITION_SHIFT_TYPE  = 63;
118 
119     /** The mask (in integer child position representation) for the child */
120     private static final long PACKED_POSITION_INT_MASK_CHILD = 0xFFFFFFFF;
121 
122     /** The mask (in integer group position representation) for the group */
123     private static final long PACKED_POSITION_INT_MASK_GROUP = 0x7FFFFFFF;
124 
125     /** Serves as the glue/translator between a ListView and an ExpandableListView */
126     private ExpandableListConnector mConnector;
127 
128     /** Gives us Views through group+child positions */
129     private ExpandableListAdapter mAdapter;
130 
131     /** Left bound for drawing the indicator. */
132     private int mIndicatorLeft;
133 
134     /** Right bound for drawing the indicator. */
135     private int mIndicatorRight;
136 
137     /**
138      * Left bound for drawing the indicator of a child. Value of
139      * {@link #CHILD_INDICATOR_INHERIT} means use mIndicatorLeft.
140      */
141     private int mChildIndicatorLeft;
142 
143     /**
144      * Right bound for drawing the indicator of a child. Value of
145      * {@link #CHILD_INDICATOR_INHERIT} means use mIndicatorRight.
146      */
147     private int mChildIndicatorRight;
148 
149     /**
150      * Denotes when a child indicator should inherit this bound from the generic
151      * indicator bounds
152      */
153     public static final int CHILD_INDICATOR_INHERIT = -1;
154 
155     /** The indicator drawn next to a group. */
156     private Drawable mGroupIndicator;
157 
158     /** The indicator drawn next to a child. */
159     private Drawable mChildIndicator;
160 
161     private static final int[] EMPTY_STATE_SET = {};
162 
163     /** State indicating the group is expanded. */
164     private static final int[] GROUP_EXPANDED_STATE_SET =
165             {R.attr.state_expanded};
166 
167     /** State indicating the group is empty (has no children). */
168     private static final int[] GROUP_EMPTY_STATE_SET =
169             {R.attr.state_empty};
170 
171     /** State indicating the group is expanded and empty (has no children). */
172     private static final int[] GROUP_EXPANDED_EMPTY_STATE_SET =
173             {R.attr.state_expanded, R.attr.state_empty};
174 
175     /** States for the group where the 0th bit is expanded and 1st bit is empty. */
176     private static final int[][] GROUP_STATE_SETS = {
177          EMPTY_STATE_SET, // 00
178          GROUP_EXPANDED_STATE_SET, // 01
179          GROUP_EMPTY_STATE_SET, // 10
180          GROUP_EXPANDED_EMPTY_STATE_SET // 11
181     };
182 
183     /** State indicating the child is the last within its group. */
184     private static final int[] CHILD_LAST_STATE_SET =
185             {R.attr.state_last};
186 
187     /** Drawable to be used as a divider when it is adjacent to any children */
188     private Drawable mChildDivider;
189     private boolean mClipChildDivider;
190 
191     // Bounds of the indicator to be drawn
192     private final Rect mIndicatorRect = new Rect();
193 
ExpandableListView(Context context)194     public ExpandableListView(Context context) {
195         this(context, null);
196     }
197 
ExpandableListView(Context context, AttributeSet attrs)198     public ExpandableListView(Context context, AttributeSet attrs) {
199         this(context, attrs, com.android.internal.R.attr.expandableListViewStyle);
200     }
201 
ExpandableListView(Context context, AttributeSet attrs, int defStyle)202     public ExpandableListView(Context context, AttributeSet attrs, int defStyle) {
203         super(context, attrs, defStyle);
204 
205         TypedArray a =
206             context.obtainStyledAttributes(attrs, com.android.internal.R.styleable.ExpandableListView, defStyle,
207                     0);
208 
209         mGroupIndicator = a
210                 .getDrawable(com.android.internal.R.styleable.ExpandableListView_groupIndicator);
211         mChildIndicator = a
212                 .getDrawable(com.android.internal.R.styleable.ExpandableListView_childIndicator);
213         mIndicatorLeft = a
214                 .getDimensionPixelSize(com.android.internal.R.styleable.ExpandableListView_indicatorLeft, 0);
215         mIndicatorRight = a
216                 .getDimensionPixelSize(com.android.internal.R.styleable.ExpandableListView_indicatorRight, 0);
217         mChildIndicatorLeft = a.getDimensionPixelSize(
218                 com.android.internal.R.styleable.ExpandableListView_childIndicatorLeft, CHILD_INDICATOR_INHERIT);
219         mChildIndicatorRight = a.getDimensionPixelSize(
220                 com.android.internal.R.styleable.ExpandableListView_childIndicatorRight, CHILD_INDICATOR_INHERIT);
221         mChildDivider = a.getDrawable(com.android.internal.R.styleable.ExpandableListView_childDivider);
222 
223         a.recycle();
224     }
225 
226 
227     @Override
dispatchDraw(Canvas canvas)228     protected void dispatchDraw(Canvas canvas) {
229         // Draw children, etc.
230         super.dispatchDraw(canvas);
231 
232         // If we have any indicators to draw, we do it here
233         if ((mChildIndicator == null) && (mGroupIndicator == null)) {
234             return;
235         }
236 
237         int saveCount = 0;
238         final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK;
239         if (clipToPadding) {
240             saveCount = canvas.save();
241             final int scrollX = mScrollX;
242             final int scrollY = mScrollY;
243             canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop,
244                     scrollX + mRight - mLeft - mPaddingRight,
245                     scrollY + mBottom - mTop - mPaddingBottom);
246         }
247 
248         final int headerViewsCount = getHeaderViewsCount();
249 
250         final int lastChildFlPos = mItemCount - getFooterViewsCount() - headerViewsCount - 1;
251 
252         final int myB = mBottom;
253 
254         PositionMetadata pos;
255         View item;
256         Drawable indicator;
257         int t, b;
258 
259         // Start at a value that is neither child nor group
260         int lastItemType = ~(ExpandableListPosition.CHILD | ExpandableListPosition.GROUP);
261 
262         final Rect indicatorRect = mIndicatorRect;
263 
264         // The "child" mentioned in the following two lines is this
265         // View's child, not referring to an expandable list's
266         // notion of a child (as opposed to a group)
267         final int childCount = getChildCount();
268         for (int i = 0, childFlPos = mFirstPosition - headerViewsCount; i < childCount;
269              i++, childFlPos++) {
270 
271             if (childFlPos < 0) {
272                 // This child is header
273                 continue;
274             } else if (childFlPos > lastChildFlPos) {
275                 // This child is footer, so are all subsequent children
276                 break;
277             }
278 
279             item = getChildAt(i);
280             t = item.getTop();
281             b = item.getBottom();
282 
283             // This item isn't on the screen
284             if ((b < 0) || (t > myB)) continue;
285 
286             // Get more expandable list-related info for this item
287             pos = mConnector.getUnflattenedPos(childFlPos);
288 
289             // If this item type and the previous item type are different, then we need to change
290             // the left & right bounds
291             if (pos.position.type != lastItemType) {
292                 if (pos.position.type == ExpandableListPosition.CHILD) {
293                     indicatorRect.left = (mChildIndicatorLeft == CHILD_INDICATOR_INHERIT) ?
294                             mIndicatorLeft : mChildIndicatorLeft;
295                     indicatorRect.right = (mChildIndicatorRight == CHILD_INDICATOR_INHERIT) ?
296                             mIndicatorRight : mChildIndicatorRight;
297                 } else {
298                     indicatorRect.left = mIndicatorLeft;
299                     indicatorRect.right = mIndicatorRight;
300                 }
301 
302                 lastItemType = pos.position.type;
303             }
304 
305             if (indicatorRect.left != indicatorRect.right) {
306                 // Use item's full height + the divider height
307                 if (mStackFromBottom) {
308                     // See ListView#dispatchDraw
309                     indicatorRect.top = t;// - mDividerHeight;
310                     indicatorRect.bottom = b;
311                 } else {
312                     indicatorRect.top = t;
313                     indicatorRect.bottom = b;// + mDividerHeight;
314                 }
315 
316                 // Get the indicator (with its state set to the item's state)
317                 indicator = getIndicator(pos);
318                 if (indicator != null) {
319                     // Draw the indicator
320                     indicator.setBounds(indicatorRect);
321                     indicator.draw(canvas);
322                 }
323             }
324 
325             pos.recycle();
326         }
327 
328         if (clipToPadding) {
329             canvas.restoreToCount(saveCount);
330         }
331     }
332 
333     /**
334      * Gets the indicator for the item at the given position. If the indicator
335      * is stateful, the state will be given to the indicator.
336      *
337      * @param pos The flat list position of the item whose indicator
338      *            should be returned.
339      * @return The indicator in the proper state.
340      */
getIndicator(PositionMetadata pos)341     private Drawable getIndicator(PositionMetadata pos) {
342         Drawable indicator;
343 
344         if (pos.position.type == ExpandableListPosition.GROUP) {
345             indicator = mGroupIndicator;
346 
347             if (indicator != null && indicator.isStateful()) {
348                 // Empty check based on availability of data.  If the groupMetadata isn't null,
349                 // we do a check on it. Otherwise, the group is collapsed so we consider it
350                 // empty for performance reasons.
351                 boolean isEmpty = (pos.groupMetadata == null) ||
352                         (pos.groupMetadata.lastChildFlPos == pos.groupMetadata.flPos);
353 
354                 final int stateSetIndex =
355                     (pos.isExpanded() ? 1 : 0) | // Expanded?
356                     (isEmpty ? 2 : 0); // Empty?
357                 indicator.setState(GROUP_STATE_SETS[stateSetIndex]);
358             }
359         } else {
360             indicator = mChildIndicator;
361 
362             if (indicator != null && indicator.isStateful()) {
363                 // No need for a state sets array for the child since it only has two states
364                 final int stateSet[] = pos.position.flatListPos == pos.groupMetadata.lastChildFlPos
365                         ? CHILD_LAST_STATE_SET
366                         : EMPTY_STATE_SET;
367                 indicator.setState(stateSet);
368             }
369         }
370 
371         return indicator;
372     }
373 
374     /**
375      * Sets the drawable that will be drawn adjacent to every child in the list. This will
376      * be drawn using the same height as the normal divider ({@link #setDivider(Drawable)}) or
377      * if it does not have an intrinsic height, the height set by {@link #setDividerHeight(int)}.
378      *
379      * @param childDivider The drawable to use.
380      */
setChildDivider(Drawable childDivider)381     public void setChildDivider(Drawable childDivider) {
382         mChildDivider = childDivider;
383         mClipChildDivider = childDivider != null && childDivider instanceof ColorDrawable;
384     }
385 
386     @Override
drawDivider(Canvas canvas, Rect bounds, int childIndex)387     void drawDivider(Canvas canvas, Rect bounds, int childIndex) {
388         int flatListPosition = childIndex + mFirstPosition;
389 
390         // Only proceed as possible child if the divider isn't above all items (if it is above
391         // all items, then the item below it has to be a group)
392         if (flatListPosition >= 0) {
393             PositionMetadata pos = mConnector.getUnflattenedPos(flatListPosition);
394             // If this item is a child, or it is a non-empty group that is expanded
395             if ((pos.position.type == ExpandableListPosition.CHILD) || (pos.isExpanded() &&
396                     pos.groupMetadata.lastChildFlPos != pos.groupMetadata.flPos)) {
397                 // These are the cases where we draw the child divider
398                 final Drawable divider = mChildDivider;
399                 final boolean clip = mClipChildDivider;
400                 if (!clip) {
401                     divider.setBounds(bounds);
402                 } else {
403                     canvas.save();
404                     canvas.clipRect(bounds);
405                 }
406                 divider.draw(canvas);
407                 if (clip) {
408                     canvas.restore();
409                 }
410                 pos.recycle();
411                 return;
412             }
413             pos.recycle();
414         }
415 
416         // Otherwise draw the default divider
417         super.drawDivider(canvas, bounds, flatListPosition);
418     }
419 
420     /**
421      * This overloaded method should not be used, instead use
422      * {@link #setAdapter(ExpandableListAdapter)}.
423      * <p>
424      * {@inheritDoc}
425      */
426     @Override
setAdapter(ListAdapter adapter)427     public void setAdapter(ListAdapter adapter) {
428         throw new RuntimeException(
429                 "For ExpandableListView, use setAdapter(ExpandableListAdapter) instead of " +
430                 "setAdapter(ListAdapter)");
431     }
432 
433     /**
434      * This method should not be used, use {@link #getExpandableListAdapter()}.
435      */
436     @Override
getAdapter()437     public ListAdapter getAdapter() {
438         /*
439          * The developer should never really call this method on an
440          * ExpandableListView, so it would be nice to throw a RuntimeException,
441          * but AdapterView calls this
442          */
443         return super.getAdapter();
444     }
445 
446     /**
447      * Register a callback to be invoked when an item has been clicked and the
448      * caller prefers to receive a ListView-style position instead of a group
449      * and/or child position. In most cases, the caller should use
450      * {@link #setOnGroupClickListener} and/or {@link #setOnChildClickListener}.
451      * <p />
452      * {@inheritDoc}
453      */
454     @Override
setOnItemClickListener(OnItemClickListener l)455     public void setOnItemClickListener(OnItemClickListener l) {
456         super.setOnItemClickListener(l);
457     }
458 
459     /**
460      * Sets the adapter that provides data to this view.
461      * @param adapter The adapter that provides data to this view.
462      */
setAdapter(ExpandableListAdapter adapter)463     public void setAdapter(ExpandableListAdapter adapter) {
464         // Set member variable
465         mAdapter = adapter;
466 
467         if (adapter != null) {
468             // Create the connector
469             mConnector = new ExpandableListConnector(adapter);
470         } else {
471             mConnector = null;
472         }
473 
474         // Link the ListView (superclass) to the expandable list data through the connector
475         super.setAdapter(mConnector);
476     }
477 
478     /**
479      * Gets the adapter that provides data to this view.
480      * @return The adapter that provides data to this view.
481      */
getExpandableListAdapter()482     public ExpandableListAdapter getExpandableListAdapter() {
483         return mAdapter;
484     }
485 
486     @Override
performItemClick(View v, int position, long id)487     public boolean performItemClick(View v, int position, long id) {
488         // Ignore clicks in header/footers
489         final int headerViewsCount = getHeaderViewsCount();
490         final int footerViewsStart = mItemCount - getFooterViewsCount();
491 
492         if (position < headerViewsCount || position >= footerViewsStart) {
493             // Clicked on a header/footer, so ignore pass it on to super
494             return super.performItemClick(v, position, id);
495         }
496 
497         // Internally handle the item click
498         return handleItemClick(v, position - headerViewsCount, id);
499     }
500 
501     /**
502      * This will either expand/collapse groups (if a group was clicked) or pass
503      * on the click to the proper child (if a child was clicked)
504      *
505      * @param position The flat list position. This has already been factored to
506      *            remove the header/footer.
507      * @param id The ListAdapter ID, not the group or child ID.
508      */
handleItemClick(View v, int position, long id)509     boolean handleItemClick(View v, int position, long id) {
510         final PositionMetadata posMetadata = mConnector.getUnflattenedPos(position);
511 
512         id = getChildOrGroupId(posMetadata.position);
513 
514         boolean returnValue;
515         if (posMetadata.position.type == ExpandableListPosition.GROUP) {
516             /* It's a group, so handle collapsing/expanding */
517 
518             if (posMetadata.isExpanded()) {
519                 /* Collapse it */
520                 mConnector.collapseGroup(posMetadata);
521 
522                 playSoundEffect(SoundEffectConstants.CLICK);
523 
524                 if (mOnGroupCollapseListener != null) {
525                     mOnGroupCollapseListener.onGroupCollapse(posMetadata.position.groupPos);
526                 }
527 
528             } else {
529                 /* It's a group click, so pass on event */
530                 if (mOnGroupClickListener != null) {
531                     if (mOnGroupClickListener.onGroupClick(this, v,
532                             posMetadata.position.groupPos, id)) {
533                         posMetadata.recycle();
534                         return true;
535                     }
536                 }
537 
538                 /* Expand it */
539                 mConnector.expandGroup(posMetadata);
540 
541                 playSoundEffect(SoundEffectConstants.CLICK);
542 
543                 if (mOnGroupExpandListener != null) {
544                     mOnGroupExpandListener.onGroupExpand(posMetadata.position.groupPos);
545                 }
546             }
547 
548             returnValue = true;
549         } else {
550             /* It's a child, so pass on event */
551             if (mOnChildClickListener != null) {
552                 playSoundEffect(SoundEffectConstants.CLICK);
553                 return mOnChildClickListener.onChildClick(this, v, posMetadata.position.groupPos,
554                         posMetadata.position.childPos, id);
555             }
556 
557             returnValue = false;
558         }
559 
560         posMetadata.recycle();
561 
562         return returnValue;
563     }
564 
565     /**
566      * Expand a group in the grouped list view
567      *
568      * @param groupPos the group to be expanded
569      * @return True if the group was expanded, false otherwise (if the group
570      *         was already expanded, this will return false)
571      */
expandGroup(int groupPos)572     public boolean expandGroup(int groupPos) {
573         boolean retValue = mConnector.expandGroup(groupPos);
574 
575         if (mOnGroupExpandListener != null) {
576             mOnGroupExpandListener.onGroupExpand(groupPos);
577         }
578 
579         return retValue;
580     }
581 
582     /**
583      * Collapse a group in the grouped list view
584      *
585      * @param groupPos position of the group to collapse
586      * @return True if the group was collapsed, false otherwise (if the group
587      *         was already collapsed, this will return false)
588      */
collapseGroup(int groupPos)589     public boolean collapseGroup(int groupPos) {
590         boolean retValue = mConnector.collapseGroup(groupPos);
591 
592         if (mOnGroupCollapseListener != null) {
593             mOnGroupCollapseListener.onGroupCollapse(groupPos);
594         }
595 
596         return retValue;
597     }
598 
599     /** Used for being notified when a group is collapsed */
600     public interface OnGroupCollapseListener {
601         /**
602          * Callback method to be invoked when a group in this expandable list has
603          * been collapsed.
604          *
605          * @param groupPosition The group position that was collapsed
606          */
onGroupCollapse(int groupPosition)607         void onGroupCollapse(int groupPosition);
608     }
609 
610     private OnGroupCollapseListener mOnGroupCollapseListener;
611 
setOnGroupCollapseListener( OnGroupCollapseListener onGroupCollapseListener)612     public void setOnGroupCollapseListener(
613             OnGroupCollapseListener onGroupCollapseListener) {
614         mOnGroupCollapseListener = onGroupCollapseListener;
615     }
616 
617     /** Used for being notified when a group is expanded */
618     public interface OnGroupExpandListener {
619         /**
620          * Callback method to be invoked when a group in this expandable list has
621          * been expanded.
622          *
623          * @param groupPosition The group position that was expanded
624          */
onGroupExpand(int groupPosition)625         void onGroupExpand(int groupPosition);
626     }
627 
628     private OnGroupExpandListener mOnGroupExpandListener;
629 
setOnGroupExpandListener( OnGroupExpandListener onGroupExpandListener)630     public void setOnGroupExpandListener(
631             OnGroupExpandListener onGroupExpandListener) {
632         mOnGroupExpandListener = onGroupExpandListener;
633     }
634 
635     /**
636      * Interface definition for a callback to be invoked when a group in this
637      * expandable list has been clicked.
638      */
639     public interface OnGroupClickListener {
640         /**
641          * Callback method to be invoked when a group in this expandable list has
642          * been clicked.
643          *
644          * @param parent The ExpandableListConnector where the click happened
645          * @param v The view within the expandable list/ListView that was clicked
646          * @param groupPosition The group position that was clicked
647          * @param id The row id of the group that was clicked
648          * @return True if the click was handled
649          */
onGroupClick(ExpandableListView parent, View v, int groupPosition, long id)650         boolean onGroupClick(ExpandableListView parent, View v, int groupPosition,
651                 long id);
652     }
653 
654     private OnGroupClickListener mOnGroupClickListener;
655 
setOnGroupClickListener(OnGroupClickListener onGroupClickListener)656     public void setOnGroupClickListener(OnGroupClickListener onGroupClickListener) {
657         mOnGroupClickListener = onGroupClickListener;
658     }
659 
660     /**
661      * Interface definition for a callback to be invoked when a child in this
662      * expandable list has been clicked.
663      */
664     public interface OnChildClickListener {
665         /**
666          * Callback method to be invoked when a child in this expandable list has
667          * been clicked.
668          *
669          * @param parent The ExpandableListView where the click happened
670          * @param v The view within the expandable list/ListView that was clicked
671          * @param groupPosition The group position that contains the child that
672          *        was clicked
673          * @param childPosition The child position within the group
674          * @param id The row id of the child that was clicked
675          * @return True if the click was handled
676          */
onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id)677         boolean onChildClick(ExpandableListView parent, View v, int groupPosition,
678                 int childPosition, long id);
679     }
680 
681     private OnChildClickListener mOnChildClickListener;
682 
setOnChildClickListener(OnChildClickListener onChildClickListener)683     public void setOnChildClickListener(OnChildClickListener onChildClickListener) {
684         mOnChildClickListener = onChildClickListener;
685     }
686 
687     /**
688      * Converts a flat list position (the raw position of an item (child or
689      * group) in the list) to an group and/or child position (represented in a
690      * packed position). This is useful in situations where the caller needs to
691      * use the underlying {@link ListView}'s methods. Use
692      * {@link ExpandableListView#getPackedPositionType} ,
693      * {@link ExpandableListView#getPackedPositionChild},
694      * {@link ExpandableListView#getPackedPositionGroup} to unpack.
695      *
696      * @param flatListPosition The flat list position to be converted.
697      * @return The group and/or child position for the given flat list position
698      *         in packed position representation.
699      */
getExpandableListPosition(int flatListPosition)700     public long getExpandableListPosition(int flatListPosition) {
701         PositionMetadata pm = mConnector.getUnflattenedPos(flatListPosition);
702         long packedPos = pm.position.getPackedPosition();
703         pm.recycle();
704         return packedPos;
705     }
706 
707     /**
708      * Converts a group and/or child position to a flat list position. This is
709      * useful in situations where the caller needs to use the underlying
710      * {@link ListView}'s methods.
711      *
712      * @param packedPosition The group and/or child positions to be converted in
713      *            packed position representation. Use
714      *            {@link #getPackedPositionForChild(int, int)} or
715      *            {@link #getPackedPositionForGroup(int)}.
716      * @return The flat list position for the given child or group.
717      */
getFlatListPosition(long packedPosition)718     public int getFlatListPosition(long packedPosition) {
719         PositionMetadata pm = mConnector.getFlattenedPos(ExpandableListPosition
720                 .obtainPosition(packedPosition));
721         int retValue = pm.position.flatListPos;
722         pm.recycle();
723         return retValue;
724     }
725 
726     /**
727      * Gets the position of the currently selected group or child (along with
728      * its type). Can return {@link #PACKED_POSITION_VALUE_NULL} if no selection.
729      *
730      * @return A packed position containing the currently selected group or
731      *         child's position and type. #PACKED_POSITION_VALUE_NULL if no selection.
732      */
getSelectedPosition()733     public long getSelectedPosition() {
734         final int selectedPos = getSelectedItemPosition();
735         if (selectedPos == -1) return PACKED_POSITION_VALUE_NULL;
736 
737         return getExpandableListPosition(selectedPos);
738     }
739 
740     /**
741      * Gets the ID of the currently selected group or child. Can return -1 if no
742      * selection.
743      *
744      * @return The ID of the currently selected group or child. -1 if no
745      *         selection.
746      */
getSelectedId()747     public long getSelectedId() {
748         long packedPos = getSelectedPosition();
749         if (packedPos == PACKED_POSITION_VALUE_NULL) return -1;
750 
751         int groupPos = getPackedPositionGroup(packedPos);
752 
753         if (getPackedPositionType(packedPos) == PACKED_POSITION_TYPE_GROUP) {
754             // It's a group
755             return mAdapter.getGroupId(groupPos);
756         } else {
757             // It's a child
758             return mAdapter.getChildId(groupPos, getPackedPositionChild(packedPos));
759         }
760     }
761 
762     /**
763      * Sets the selection to the specified group.
764      * @param groupPosition The position of the group that should be selected.
765      */
setSelectedGroup(int groupPosition)766     public void setSelectedGroup(int groupPosition) {
767         ExpandableListPosition elGroupPos = ExpandableListPosition
768                 .obtainGroupPosition(groupPosition);
769         PositionMetadata pm = mConnector.getFlattenedPos(elGroupPos);
770         elGroupPos.recycle();
771         super.setSelection(pm.position.flatListPos);
772         pm.recycle();
773     }
774 
775     /**
776      * Sets the selection to the specified child. If the child is in a collapsed
777      * group, the group will only be expanded and child subsequently selected if
778      * shouldExpandGroup is set to true, otherwise the method will return false.
779      *
780      * @param groupPosition The position of the group that contains the child.
781      * @param childPosition The position of the child within the group.
782      * @param shouldExpandGroup Whether the child's group should be expanded if
783      *            it is collapsed.
784      * @return Whether the selection was successfully set on the child.
785      */
setSelectedChild(int groupPosition, int childPosition, boolean shouldExpandGroup)786     public boolean setSelectedChild(int groupPosition, int childPosition, boolean shouldExpandGroup) {
787         ExpandableListPosition elChildPos = ExpandableListPosition.obtainChildPosition(
788                 groupPosition, childPosition);
789         PositionMetadata flatChildPos = mConnector.getFlattenedPos(elChildPos);
790 
791         if (flatChildPos == null) {
792             // The child's group isn't expanded
793 
794             // Shouldn't expand the group, so return false for we didn't set the selection
795             if (!shouldExpandGroup) return false;
796 
797             expandGroup(groupPosition);
798 
799             flatChildPos = mConnector.getFlattenedPos(elChildPos);
800 
801             // Sanity check
802             if (flatChildPos == null) {
803                 throw new IllegalStateException("Could not find child");
804             }
805         }
806 
807         super.setSelection(flatChildPos.position.flatListPos);
808 
809         elChildPos.recycle();
810         flatChildPos.recycle();
811 
812         return true;
813     }
814 
815     /**
816      * Whether the given group is currently expanded.
817      *
818      * @param groupPosition The group to check.
819      * @return Whether the group is currently expanded.
820      */
isGroupExpanded(int groupPosition)821     public boolean isGroupExpanded(int groupPosition) {
822         return mConnector.isGroupExpanded(groupPosition);
823     }
824 
825     /**
826      * Gets the type of a packed position. See
827      * {@link #getPackedPositionForChild(int, int)}.
828      *
829      * @param packedPosition The packed position for which to return the type.
830      * @return The type of the position contained within the packed position,
831      *         either {@link #PACKED_POSITION_TYPE_CHILD}, {@link #PACKED_POSITION_TYPE_GROUP}, or
832      *         {@link #PACKED_POSITION_TYPE_NULL}.
833      */
getPackedPositionType(long packedPosition)834     public static int getPackedPositionType(long packedPosition) {
835         if (packedPosition == PACKED_POSITION_VALUE_NULL) {
836             return PACKED_POSITION_TYPE_NULL;
837         }
838 
839         return (packedPosition & PACKED_POSITION_MASK_TYPE) == PACKED_POSITION_MASK_TYPE
840                 ? PACKED_POSITION_TYPE_CHILD
841                 : PACKED_POSITION_TYPE_GROUP;
842     }
843 
844     /**
845      * Gets the group position from a packed position. See
846      * {@link #getPackedPositionForChild(int, int)}.
847      *
848      * @param packedPosition The packed position from which the group position
849      *            will be returned.
850      * @return The group position portion of the packed position. If this does
851      *         not contain a group, returns -1.
852      */
getPackedPositionGroup(long packedPosition)853     public static int getPackedPositionGroup(long packedPosition) {
854         // Null
855         if (packedPosition == PACKED_POSITION_VALUE_NULL) return -1;
856 
857         return (int) ((packedPosition & PACKED_POSITION_MASK_GROUP) >> PACKED_POSITION_SHIFT_GROUP);
858     }
859 
860     /**
861      * Gets the child position from a packed position that is of
862      * {@link #PACKED_POSITION_TYPE_CHILD} type (use {@link #getPackedPositionType(long)}).
863      * To get the group that this child belongs to, use
864      * {@link #getPackedPositionGroup(long)}. See
865      * {@link #getPackedPositionForChild(int, int)}.
866      *
867      * @param packedPosition The packed position from which the child position
868      *            will be returned.
869      * @return The child position portion of the packed position. If this does
870      *         not contain a child, returns -1.
871      */
getPackedPositionChild(long packedPosition)872     public static int getPackedPositionChild(long packedPosition) {
873         // Null
874         if (packedPosition == PACKED_POSITION_VALUE_NULL) return -1;
875 
876         // Group since a group type clears this bit
877         if ((packedPosition & PACKED_POSITION_MASK_TYPE) != PACKED_POSITION_MASK_TYPE) return -1;
878 
879         return (int) (packedPosition & PACKED_POSITION_MASK_CHILD);
880     }
881 
882     /**
883      * Returns the packed position representation of a child's position.
884      * <p>
885      * In general, a packed position should be used in
886      * situations where the position given to/returned from an
887      * {@link ExpandableListAdapter} or {@link ExpandableListView} method can
888      * either be a child or group. The two positions are packed into a single
889      * long which can be unpacked using
890      * {@link #getPackedPositionChild(long)},
891      * {@link #getPackedPositionGroup(long)}, and
892      * {@link #getPackedPositionType(long)}.
893      *
894      * @param groupPosition The child's parent group's position.
895      * @param childPosition The child position within the group.
896      * @return The packed position representation of the child (and parent group).
897      */
getPackedPositionForChild(int groupPosition, int childPosition)898     public static long getPackedPositionForChild(int groupPosition, int childPosition) {
899         return (((long)PACKED_POSITION_TYPE_CHILD) << PACKED_POSITION_SHIFT_TYPE)
900                 | ((((long)groupPosition) & PACKED_POSITION_INT_MASK_GROUP)
901                         << PACKED_POSITION_SHIFT_GROUP)
902                 | (childPosition & PACKED_POSITION_INT_MASK_CHILD);
903     }
904 
905     /**
906      * Returns the packed position representation of a group's position. See
907      * {@link #getPackedPositionForChild(int, int)}.
908      *
909      * @param groupPosition The child's parent group's position.
910      * @return The packed position representation of the group.
911      */
getPackedPositionForGroup(int groupPosition)912     public static long getPackedPositionForGroup(int groupPosition) {
913         // No need to OR a type in because PACKED_POSITION_GROUP == 0
914         return ((((long)groupPosition) & PACKED_POSITION_INT_MASK_GROUP)
915                         << PACKED_POSITION_SHIFT_GROUP);
916     }
917 
918     @Override
createContextMenuInfo(View view, int flatListPosition, long id)919     ContextMenuInfo createContextMenuInfo(View view, int flatListPosition, long id) {
920         // Adjust for and handle for header views
921         final int adjustedPosition = flatListPosition - getHeaderViewsCount();
922         if (adjustedPosition < 0) {
923             // Return normal info for header view context menus
924             return new AdapterContextMenuInfo(view, flatListPosition, id);
925         }
926 
927         PositionMetadata pm = mConnector.getUnflattenedPos(adjustedPosition);
928         ExpandableListPosition pos = pm.position;
929         pm.recycle();
930 
931         id = getChildOrGroupId(pos);
932         long packedPosition = pos.getPackedPosition();
933         pos.recycle();
934 
935         return new ExpandableListContextMenuInfo(view, packedPosition, id);
936     }
937 
938     /**
939      * Gets the ID of the group or child at the given <code>position</code>.
940      * This is useful since there is no ListAdapter ID -> ExpandableListAdapter
941      * ID conversion mechanism (in some cases, it isn't possible).
942      *
943      * @param position The position of the child or group whose ID should be
944      *            returned.
945      */
getChildOrGroupId(ExpandableListPosition position)946     private long getChildOrGroupId(ExpandableListPosition position) {
947         if (position.type == ExpandableListPosition.CHILD) {
948             return mAdapter.getChildId(position.groupPos, position.childPos);
949         } else {
950             return mAdapter.getGroupId(position.groupPos);
951         }
952     }
953 
954     /**
955      * Sets the indicator to be drawn next to a child.
956      *
957      * @param childIndicator The drawable to be used as an indicator. If the
958      *            child is the last child for a group, the state
959      *            {@link android.R.attr#state_last} will be set.
960      */
setChildIndicator(Drawable childIndicator)961     public void setChildIndicator(Drawable childIndicator) {
962         mChildIndicator = childIndicator;
963     }
964 
965     /**
966      * Sets the drawing bounds for the child indicator. For either, you can
967      * specify {@link #CHILD_INDICATOR_INHERIT} to use inherit from the general
968      * indicator's bounds.
969      *
970      * @see #setIndicatorBounds(int, int)
971      * @param left The left position (relative to the left bounds of this View)
972      *            to start drawing the indicator.
973      * @param right The right position (relative to the left bounds of this
974      *            View) to end the drawing of the indicator.
975      */
setChildIndicatorBounds(int left, int right)976     public void setChildIndicatorBounds(int left, int right) {
977         mChildIndicatorLeft = left;
978         mChildIndicatorRight = right;
979     }
980 
981     /**
982      * Sets the indicator to be drawn next to a group.
983      *
984      * @param groupIndicator The drawable to be used as an indicator. If the
985      *            group is empty, the state {@link android.R.attr#state_empty} will be
986      *            set. If the group is expanded, the state
987      *            {@link android.R.attr#state_expanded} will be set.
988      */
setGroupIndicator(Drawable groupIndicator)989     public void setGroupIndicator(Drawable groupIndicator) {
990         mGroupIndicator = groupIndicator;
991     }
992 
993     /**
994      * Sets the drawing bounds for the indicators (at minimum, the group indicator
995      * is affected by this; the child indicator is affected by this if the
996      * child indicator bounds are set to inherit).
997      *
998      * @see #setChildIndicatorBounds(int, int)
999      * @param left The left position (relative to the left bounds of this View)
1000      *            to start drawing the indicator.
1001      * @param right The right position (relative to the left bounds of this
1002      *            View) to end the drawing of the indicator.
1003      */
setIndicatorBounds(int left, int right)1004     public void setIndicatorBounds(int left, int right) {
1005         mIndicatorLeft = left;
1006         mIndicatorRight = right;
1007     }
1008 
1009     /**
1010      * Extra menu information specific to an {@link ExpandableListView} provided
1011      * to the
1012      * {@link android.view.View.OnCreateContextMenuListener#onCreateContextMenu(ContextMenu, View, ContextMenuInfo) }
1013      * callback when a context menu is brought up for this AdapterView.
1014      */
1015     public static class ExpandableListContextMenuInfo implements ContextMenu.ContextMenuInfo {
1016 
ExpandableListContextMenuInfo(View targetView, long packedPosition, long id)1017         public ExpandableListContextMenuInfo(View targetView, long packedPosition, long id) {
1018             this.targetView = targetView;
1019             this.packedPosition = packedPosition;
1020             this.id = id;
1021         }
1022 
1023         /**
1024          * The view for which the context menu is being displayed. This
1025          * will be one of the children Views of this {@link ExpandableListView}.
1026          */
1027         public View targetView;
1028 
1029         /**
1030          * The packed position in the list represented by the adapter for which
1031          * the context menu is being displayed. Use the methods
1032          * {@link ExpandableListView#getPackedPositionType},
1033          * {@link ExpandableListView#getPackedPositionChild}, and
1034          * {@link ExpandableListView#getPackedPositionGroup} to unpack this.
1035          */
1036         public long packedPosition;
1037 
1038         /**
1039          * The ID of the item (group or child) for which the context menu is
1040          * being displayed.
1041          */
1042         public long id;
1043     }
1044 
1045     static class SavedState extends BaseSavedState {
1046         ArrayList<ExpandableListConnector.GroupMetadata> expandedGroupMetadataList;
1047 
1048         /**
1049          * Constructor called from {@link ExpandableListView#onSaveInstanceState()}
1050          */
SavedState( Parcelable superState, ArrayList<ExpandableListConnector.GroupMetadata> expandedGroupMetadataList)1051         SavedState(
1052                 Parcelable superState,
1053                 ArrayList<ExpandableListConnector.GroupMetadata> expandedGroupMetadataList) {
1054             super(superState);
1055             this.expandedGroupMetadataList = expandedGroupMetadataList;
1056         }
1057 
1058         /**
1059          * Constructor called from {@link #CREATOR}
1060          */
SavedState(Parcel in)1061         private SavedState(Parcel in) {
1062             super(in);
1063             expandedGroupMetadataList = new ArrayList<ExpandableListConnector.GroupMetadata>();
1064             in.readList(expandedGroupMetadataList, ExpandableListConnector.class.getClassLoader());
1065         }
1066 
1067         @Override
writeToParcel(Parcel out, int flags)1068         public void writeToParcel(Parcel out, int flags) {
1069             super.writeToParcel(out, flags);
1070             out.writeList(expandedGroupMetadataList);
1071         }
1072 
1073         public static final Parcelable.Creator<SavedState> CREATOR
1074                 = new Parcelable.Creator<SavedState>() {
1075             public SavedState createFromParcel(Parcel in) {
1076                 return new SavedState(in);
1077             }
1078 
1079             public SavedState[] newArray(int size) {
1080                 return new SavedState[size];
1081             }
1082         };
1083     }
1084 
1085     @Override
onSaveInstanceState()1086     public Parcelable onSaveInstanceState() {
1087         Parcelable superState = super.onSaveInstanceState();
1088         return new SavedState(superState,
1089                 mConnector != null ? mConnector.getExpandedGroupMetadataList() : null);
1090     }
1091 
1092     @Override
onRestoreInstanceState(Parcelable state)1093     public void onRestoreInstanceState(Parcelable state) {
1094         if (!(state instanceof SavedState)) {
1095             super.onRestoreInstanceState(state);
1096             return;
1097         }
1098 
1099         SavedState ss = (SavedState) state;
1100         super.onRestoreInstanceState(ss.getSuperState());
1101 
1102         if (mConnector != null && ss.expandedGroupMetadataList != null) {
1103             mConnector.setExpandedGroupMetadataList(ss.expandedGroupMetadataList);
1104         }
1105     }
1106 
1107 }
1108