Android example source code file (ExpandableListConnector.java)
The ExpandableListConnector.java Android example source code/*
* Copyright (C) 2007 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 android.widget;
import android.database.DataSetObserver;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.SystemClock;
import android.view.View;
import android.view.ViewGroup;
import java.util.ArrayList;
import java.util.Collections;
/*
* Implementation notes:
*
* <p>
* Terminology:
* <li> flPos - Flat list position, the position used by ListView
* <li> gPos - Group position, the position of a group among all the groups
* <li> cPos - Child position, the position of a child among all the children
* in a group
*/
/**
* A {@link BaseAdapter} that provides data/Views in an expandable list (offers
* features such as collapsing/expanding groups containing children). By
* itself, this adapter has no data and is a connector to a
* {@link ExpandableListAdapter} which provides the data.
* <p>
* Internally, this connector translates the flat list position that the
* ListAdapter expects to/from group and child positions that the ExpandableListAdapter
* expects.
*/
class ExpandableListConnector extends BaseAdapter implements Filterable {
/**
* The ExpandableListAdapter to fetch the data/Views for this expandable list
*/
private ExpandableListAdapter mExpandableListAdapter;
/**
* List of metadata for the currently expanded groups. The metadata consists
* of data essential for efficiently translating between flat list positions
* and group/child positions. See {@link GroupMetadata}.
*/
private ArrayList<GroupMetadata> mExpGroupMetadataList;
/** The number of children from all currently expanded groups */
private int mTotalExpChildrenCount;
/** The maximum number of allowable expanded groups. Defaults to 'no limit' */
private int mMaxExpGroupCount = Integer.MAX_VALUE;
/** Change observer used to have ExpandableListAdapter changes pushed to us */
private final DataSetObserver mDataSetObserver = new MyDataSetObserver();
/**
* Constructs the connector
*/
public ExpandableListConnector(ExpandableListAdapter expandableListAdapter) {
mExpGroupMetadataList = new ArrayList<GroupMetadata>();
setExpandableListAdapter(expandableListAdapter);
}
/**
* Point to the {@link ExpandableListAdapter} that will give us data/Views
*
* @param expandableListAdapter the adapter that supplies us with data/Views
*/
public void setExpandableListAdapter(ExpandableListAdapter expandableListAdapter) {
if (mExpandableListAdapter != null) {
mExpandableListAdapter.unregisterDataSetObserver(mDataSetObserver);
}
mExpandableListAdapter = expandableListAdapter;
expandableListAdapter.registerDataSetObserver(mDataSetObserver);
}
/**
* Translates a flat list position to either a) group pos if the specified
* flat list position corresponds to a group, or b) child pos if it
* corresponds to a child. Performs a binary search on the expanded
* groups list to find the flat list pos if it is an exp group, otherwise
* finds where the flat list pos fits in between the exp groups.
*
* @param flPos the flat list position to be translated
* @return the group position or child position of the specified flat list
* position encompassed in a {@link PositionMetadata} object
* that contains additional useful info for insertion, etc.
*/
PositionMetadata getUnflattenedPos(final int flPos) {
/* Keep locally since frequent use */
final ArrayList<GroupMetadata> egml = mExpGroupMetadataList;
final int numExpGroups = egml.size();
/* Binary search variables */
int leftExpGroupIndex = 0;
int rightExpGroupIndex = numExpGroups - 1;
int midExpGroupIndex = 0;
GroupMetadata midExpGm;
if (numExpGroups == 0) {
/*
* There aren't any expanded groups (hence no visible children
* either), so flPos must be a group and its group pos will be the
* same as its flPos
*/
return PositionMetadata.obtain(flPos, ExpandableListPosition.GROUP, flPos,
-1, null, 0);
}
/*
* Binary search over the expanded groups to find either the exact
* expanded group (if we're looking for a group) or the group that
* contains the child we're looking for. If we are looking for a
* collapsed group, we will not have a direct match here, but we will
* find the expanded group just before the group we're searching for (so
* then we can calculate the group position of the group we're searching
* for). If there isn't an expanded group prior to the group being
* searched for, then the group being searched for's group position is
* the same as the flat list position (since there are no children before
* it, and all groups before it are collapsed).
*/
while (leftExpGroupIndex <= rightExpGroupIndex) {
midExpGroupIndex =
(rightExpGroupIndex - leftExpGroupIndex) / 2
+ leftExpGroupIndex;
midExpGm = egml.get(midExpGroupIndex);
if (flPos > midExpGm.lastChildFlPos) {
/*
* The flat list position is after the current middle group's
* last child's flat list position, so search right
*/
leftExpGroupIndex = midExpGroupIndex + 1;
} else if (flPos < midExpGm.flPos) {
/*
* The flat list position is before the current middle group's
* flat list position, so search left
*/
rightExpGroupIndex = midExpGroupIndex - 1;
} else if (flPos == midExpGm.flPos) {
/*
* The flat list position is this middle group's flat list
* position, so we've found an exact hit
*/
return PositionMetadata.obtain(flPos, ExpandableListPosition.GROUP,
midExpGm.gPos, -1, midExpGm, midExpGroupIndex);
} else if (flPos <= midExpGm.lastChildFlPos
/* && flPos > midGm.flPos as deduced from previous
* conditions */) {
/* The flat list position is a child of the middle group */
/*
* Subtract the first child's flat list position from the
* specified flat list pos to get the child's position within
* the group
*/
final int childPos = flPos - (midExpGm.flPos + 1);
return PositionMetadata.obtain(flPos, ExpandableListPosition.CHILD,
midExpGm.gPos, childPos, midExpGm, midExpGroupIndex);
}
}
/*
* If we've reached here, it means the flat list position must be a
* group that is not expanded, since otherwise we would have hit it
* in the above search.
*/
/**
* If we are to expand this group later, where would it go in the
* mExpGroupMetadataList ?
*/
int insertPosition = 0;
/** What is its group position in the list of all groups? */
int groupPos = 0;
/*
* To figure out exact insertion and prior group positions, we need to
* determine how we broke out of the binary search. We backtrack
* to see this.
*/
if (leftExpGroupIndex > midExpGroupIndex) {
/*
* This would occur in the first conditional, so the flat list
* insertion position is after the left group. Also, the
* leftGroupPos is one more than it should be (since that broke out
* of our binary search), so we decrement it.
*/
final GroupMetadata leftExpGm = egml.get(leftExpGroupIndex-1);
insertPosition = leftExpGroupIndex;
/*
* Sums the number of groups between the prior exp group and this
* one, and then adds it to the prior group's group pos
*/
groupPos =
(flPos - leftExpGm.lastChildFlPos) + leftExpGm.gPos;
} else if (rightExpGroupIndex < midExpGroupIndex) {
/*
* This would occur in the second conditional, so the flat list
* insertion position is before the right group. Also, the
* rightGroupPos is one less than it should be, so increment it.
*/
final GroupMetadata rightExpGm = egml.get(++rightExpGroupIndex);
insertPosition = rightExpGroupIndex;
/*
* Subtracts this group's flat list pos from the group after's flat
* list position to find out how many groups are in between the two
* groups. Then, subtracts that number from the group after's group
* pos to get this group's pos.
*/
groupPos = rightExpGm.gPos - (rightExpGm.flPos - flPos);
} else {
// TODO: clean exit
throw new RuntimeException("Unknown state");
}
return PositionMetadata.obtain(flPos, ExpandableListPosition.GROUP, groupPos, -1,
null, insertPosition);
}
/**
* Translates either a group pos or a child pos (+ group it belongs to) to a
* flat list position. If searching for a child and its group is not expanded, this will
* return null since the child isn't being shown in the ListView, and hence it has no
* position.
*
* @param pos a {@link ExpandableListPosition} representing either a group position
* or child position
* @return the flat list position encompassed in a {@link PositionMetadata}
* object that contains additional useful info for insertion, etc., or null.
*/
PositionMetadata getFlattenedPos(final ExpandableListPosition pos) {
final ArrayList<GroupMetadata> egml = mExpGroupMetadataList;
final int numExpGroups = egml.size();
/* Binary search variables */
int leftExpGroupIndex = 0;
int rightExpGroupIndex = numExpGroups - 1;
int midExpGroupIndex = 0;
GroupMetadata midExpGm;
if (numExpGroups == 0) {
/*
* There aren't any expanded groups, so flPos must be a group and
* its flPos will be the same as its group pos. The
* insert position is 0 (since the list is empty).
*/
return PositionMetadata.obtain(pos.groupPos, pos.type,
pos.groupPos, pos.childPos, null, 0);
}
/*
* Binary search over the expanded groups to find either the exact
* expanded group (if we're looking for a group) or the group that
* contains the child we're looking for.
*/
while (leftExpGroupIndex <= rightExpGroupIndex) {
midExpGroupIndex = (rightExpGroupIndex - leftExpGroupIndex)/2 + leftExpGroupIndex;
midExpGm = egml.get(midExpGroupIndex);
if (pos.groupPos > midExpGm.gPos) {
/*
* It's after the current middle group, so search right
*/
leftExpGroupIndex = midExpGroupIndex + 1;
} else if (pos.groupPos < midExpGm.gPos) {
/*
* It's before the current middle group, so search left
*/
rightExpGroupIndex = midExpGroupIndex - 1;
} else if (pos.groupPos == midExpGm.gPos) {
/*
* It's this middle group, exact hit
*/
if (pos.type == ExpandableListPosition.GROUP) {
/* If it's a group, give them this matched group's flPos */
return PositionMetadata.obtain(midExpGm.flPos, pos.type,
pos.groupPos, pos.childPos, midExpGm, midExpGroupIndex);
} else if (pos.type == ExpandableListPosition.CHILD) {
/* If it's a child, calculate the flat list pos */
return PositionMetadata.obtain(midExpGm.flPos + pos.childPos
+ 1, pos.type, pos.groupPos, pos.childPos,
midExpGm, midExpGroupIndex);
} else {
return null;
}
}
}
/*
* If we've reached here, it means there was no match in the expanded
* groups, so it must be a collapsed group that they're search for
*/
if (pos.type != ExpandableListPosition.GROUP) {
/* If it isn't a group, return null */
return null;
}
/*
* To figure out exact insertion and prior group positions, we need to
* determine how we broke out of the binary search. We backtrack to see
* this.
*/
if (leftExpGroupIndex > midExpGroupIndex) {
/*
* This would occur in the first conditional, so the flat list
* insertion position is after the left group.
*
* The leftGroupPos is one more than it should be (from the binary
* search loop) so we subtract 1 to get the actual left group. Since
* the insertion point is AFTER the left group, we keep this +1
* value as the insertion point
*/
final GroupMetadata leftExpGm = egml.get(leftExpGroupIndex-1);
final int flPos =
leftExpGm.lastChildFlPos
+ (pos.groupPos - leftExpGm.gPos);
return PositionMetadata.obtain(flPos, pos.type, pos.groupPos,
pos.childPos, null, leftExpGroupIndex);
} else if (rightExpGroupIndex < midExpGroupIndex) {
/*
* This would occur in the second conditional, so the flat list
* insertion position is before the right group. Also, the
* rightGroupPos is one less than it should be (from binary search
* loop), so we increment to it.
*/
final GroupMetadata rightExpGm = egml.get(++rightExpGroupIndex);
final int flPos =
rightExpGm.flPos
- (rightExpGm.gPos - pos.groupPos);
return PositionMetadata.obtain(flPos, pos.type, pos.groupPos,
pos.childPos, null, rightExpGroupIndex);
} else {
return null;
}
}
@Override
public boolean areAllItemsEnabled() {
return mExpandableListAdapter.areAllItemsEnabled();
}
@Override
public boolean isEnabled(int flatListPos) {
final ExpandableListPosition pos = getUnflattenedPos(flatListPos).position;
boolean retValue;
if (pos.type == ExpandableListPosition.CHILD) {
retValue = mExpandableListAdapter.isChildSelectable(pos.groupPos, pos.childPos);
} else {
// Groups are always selectable
retValue = true;
}
pos.recycle();
return retValue;
}
public int getCount() {
/*
* Total count for the list view is the number groups plus the
* number of children from currently expanded groups (a value we keep
* cached in this class)
*/
return mExpandableListAdapter.getGroupCount() + mTotalExpChildrenCount;
}
public Object getItem(int flatListPos) {
final PositionMetadata posMetadata = getUnflattenedPos(flatListPos);
Object retValue;
if (posMetadata.position.type == ExpandableListPosition.GROUP) {
retValue = mExpandableListAdapter
.getGroup(posMetadata.position.groupPos);
} else if (posMetadata.position.type == ExpandableListPosition.CHILD) {
retValue = mExpandableListAdapter.getChild(posMetadata.position.groupPos,
posMetadata.position.childPos);
} else {
// TODO: clean exit
throw new RuntimeException("Flat list position is of unknown type");
}
posMetadata.recycle();
return retValue;
}
public long getItemId(int flatListPos) {
final PositionMetadata posMetadata = getUnflattenedPos(flatListPos);
final long groupId = mExpandableListAdapter.getGroupId(posMetadata.position.groupPos);
long retValue;
if (posMetadata.position.type == ExpandableListPosition.GROUP) {
retValue = mExpandableListAdapter.getCombinedGroupId(groupId);
} else if (posMetadata.position.type == ExpandableListPosition.CHILD) {
final long childId = mExpandableListAdapter.getChildId(posMetadata.position.groupPos,
posMetadata.position.childPos);
retValue = mExpandableListAdapter.getCombinedChildId(groupId, childId);
} else {
// TODO: clean exit
throw new RuntimeException("Flat list position is of unknown type");
}
posMetadata.recycle();
return retValue;
}
public View getView(int flatListPos, View convertView, ViewGroup parent) {
final PositionMetadata posMetadata = getUnflattenedPos(flatListPos);
View retValue;
if (posMetadata.position.type == ExpandableListPosition.GROUP) {
retValue = mExpandableListAdapter.getGroupView(posMetadata.position.groupPos,
posMetadata.isExpanded(), convertView, parent);
} else if (posMetadata.position.type == ExpandableListPosition.CHILD) {
final boolean isLastChild = posMetadata.groupMetadata.lastChildFlPos == flatListPos;
retValue = mExpandableListAdapter.getChildView(posMetadata.position.groupPos,
posMetadata.position.childPos, isLastChild, convertView, parent);
} else {
// TODO: clean exit
throw new RuntimeException("Flat list position is of unknown type");
}
posMetadata.recycle();
return retValue;
}
@Override
public int getItemViewType(int flatListPos) {
final ExpandableListPosition pos = getUnflattenedPos(flatListPos).position;
int retValue;
if (mExpandableListAdapter instanceof HeterogeneousExpandableList) {
HeterogeneousExpandableList adapter =
(HeterogeneousExpandableList) mExpandableListAdapter;
if (pos.type == ExpandableListPosition.GROUP) {
retValue = adapter.getGroupType(pos.groupPos);
} else {
final int childType = adapter.getChildType(pos.groupPos, pos.childPos);
retValue = adapter.getGroupTypeCount() + childType;
}
} else {
if (pos.type == ExpandableListPosition.GROUP) {
retValue = 0;
} else {
retValue = 1;
}
}
pos.recycle();
return retValue;
}
@Override
public int getViewTypeCount() {
if (mExpandableListAdapter instanceof HeterogeneousExpandableList) {
HeterogeneousExpandableList adapter =
(HeterogeneousExpandableList) mExpandableListAdapter;
return adapter.getGroupTypeCount() + adapter.getChildTypeCount();
} else {
return 2;
}
}
@Override
public boolean hasStableIds() {
return mExpandableListAdapter.hasStableIds();
}
/**
* Traverses the expanded group metadata list and fills in the flat list
* positions.
*
* @param forceChildrenCountRefresh Forces refreshing of the children count
* for all expanded groups.
* @param syncGroupPositions Whether to search for the group positions
* based on the group IDs. This should only be needed when calling
* this from an onChanged callback.
*/
@SuppressWarnings("unchecked")
private void refreshExpGroupMetadataList(boolean forceChildrenCountRefresh,
boolean syncGroupPositions) {
final ArrayList<GroupMetadata> egml = mExpGroupMetadataList;
int egmlSize = egml.size();
int curFlPos = 0;
/* Update child count as we go through */
mTotalExpChildrenCount = 0;
if (syncGroupPositions) {
// We need to check whether any groups have moved positions
boolean positionsChanged = false;
for (int i = egmlSize - 1; i >= 0; i--) {
GroupMetadata curGm = egml.get(i);
int newGPos = findGroupPosition(curGm.gId, curGm.gPos);
if (newGPos != curGm.gPos) {
if (newGPos == AdapterView.INVALID_POSITION) {
// Doh, just remove it from the list of expanded groups
egml.remove(i);
egmlSize--;
}
curGm.gPos = newGPos;
if (!positionsChanged) positionsChanged = true;
}
}
if (positionsChanged) {
// At least one group changed positions, so re-sort
Collections.sort(egml);
}
}
int gChildrenCount;
int lastGPos = 0;
for (int i = 0; i < egmlSize; i++) {
/* Store in local variable since we'll access freq */
GroupMetadata curGm = egml.get(i);
/*
* Get the number of children, try to refrain from calling
* another class's method unless we have to (so do a subtraction)
*/
if ((curGm.lastChildFlPos == GroupMetadata.REFRESH) || forceChildrenCountRefresh) {
gChildrenCount = mExpandableListAdapter.getChildrenCount(curGm.gPos);
} else {
/* Num children for this group is its last child's fl pos minus
* the group's fl pos
*/
gChildrenCount = curGm.lastChildFlPos - curGm.flPos;
}
/* Update */
mTotalExpChildrenCount += gChildrenCount;
/*
* This skips the collapsed groups and increments the flat list
* position (for subsequent exp groups) by accounting for the collapsed
* groups
*/
curFlPos += (curGm.gPos - lastGPos);
lastGPos = curGm.gPos;
/* Update the flat list positions, and the current flat list pos */
curGm.flPos = curFlPos;
curFlPos += gChildrenCount;
curGm.lastChildFlPos = curFlPos;
}
}
/**
* Collapse a group in the grouped list view
*
* @param groupPos position of the group to collapse
*/
boolean collapseGroup(int groupPos) {
PositionMetadata pm = getFlattenedPos(ExpandableListPosition.obtain(
ExpandableListPosition.GROUP, groupPos, -1, -1));
if (pm == null) return false;
boolean retValue = collapseGroup(pm);
pm.recycle();
return retValue;
}
boolean collapseGroup(PositionMetadata posMetadata) {
/*
* Collapsing requires removal from mExpGroupMetadataList
*/
/*
* If it is null, it must be already collapsed. This group metadata
* object should have been set from the search that returned the
* position metadata object.
*/
if (posMetadata.groupMetadata == null) return false;
// Remove the group from the list of expanded groups
mExpGroupMetadataList.remove(posMetadata.groupMetadata);
// Refresh the metadata
refreshExpGroupMetadataList(false, false);
// Notify of change
notifyDataSetChanged();
// Give the callback
mExpandableListAdapter.onGroupCollapsed(posMetadata.groupMetadata.gPos);
return true;
}
/**
* Expand a group in the grouped list view
* @param groupPos the group to be expanded
*/
boolean expandGroup(int groupPos) {
PositionMetadata pm = getFlattenedPos(ExpandableListPosition.obtain(
ExpandableListPosition.GROUP, groupPos, -1, -1));
boolean retValue = expandGroup(pm);
pm.recycle();
return retValue;
}
boolean expandGroup(PositionMetadata posMetadata) {
/*
* Expanding requires insertion into the mExpGroupMetadataList
*/
if (posMetadata.position.groupPos < 0) {
// TODO clean exit
throw new RuntimeException("Need group");
}
if (mMaxExpGroupCount == 0) return false;
// Check to see if it's already expanded
if (posMetadata.groupMetadata != null) return false;
/* Restrict number of expanded groups to mMaxExpGroupCount */
if (mExpGroupMetadataList.size() >= mMaxExpGroupCount) {
/* Collapse a group */
// TODO: Collapse something not on the screen instead of the first one?
// TODO: Could write overloaded function to take GroupMetadata to collapse
GroupMetadata collapsedGm = mExpGroupMetadataList.get(0);
int collapsedIndex = mExpGroupMetadataList.indexOf(collapsedGm);
collapseGroup(collapsedGm.gPos);
/* Decrement index if it is after the group we removed */
if (posMetadata.groupInsertIndex > collapsedIndex) {
posMetadata.groupInsertIndex--;
}
}
GroupMetadata expandedGm = GroupMetadata.obtain(
GroupMetadata.REFRESH,
GroupMetadata.REFRESH,
posMetadata.position.groupPos,
mExpandableListAdapter.getGroupId(posMetadata.position.groupPos));
mExpGroupMetadataList.add(posMetadata.groupInsertIndex, expandedGm);
// Refresh the metadata
refreshExpGroupMetadataList(false, false);
// Notify of change
notifyDataSetChanged();
// Give the callback
mExpandableListAdapter.onGroupExpanded(expandedGm.gPos);
return true;
}
/**
* Whether the given group is currently expanded.
* @param groupPosition The group to check.
* @return Whether the group is currently expanded.
*/
public boolean isGroupExpanded(int groupPosition) {
GroupMetadata groupMetadata;
for (int i = mExpGroupMetadataList.size() - 1; i >= 0; i--) {
groupMetadata = mExpGroupMetadataList.get(i);
if (groupMetadata.gPos == groupPosition) {
return true;
}
}
return false;
}
/**
* Set the maximum number of groups that can be expanded at any given time
*/
public void setMaxExpGroupCount(int maxExpGroupCount) {
mMaxExpGroupCount = maxExpGroupCount;
}
ExpandableListAdapter getAdapter() {
return mExpandableListAdapter;
}
public Filter getFilter() {
ExpandableListAdapter adapter = getAdapter();
if (adapter instanceof Filterable) {
return ((Filterable) adapter).getFilter();
} else {
return null;
}
}
ArrayList<GroupMetadata> getExpandedGroupMetadataList() {
return mExpGroupMetadataList;
}
void setExpandedGroupMetadataList(ArrayList<GroupMetadata> expandedGroupMetadataList) {
if ((expandedGroupMetadataList == null) || (mExpandableListAdapter == null)) {
return;
}
// Make sure our current data set is big enough for the previously
// expanded groups, if not, ignore this request
int numGroups = mExpandableListAdapter.getGroupCount();
for (int i = expandedGroupMetadataList.size() - 1; i >= 0; i--) {
if (expandedGroupMetadataList.get(i).gPos >= numGroups) {
// Doh, for some reason the client doesn't have some of the groups
return;
}
}
mExpGroupMetadataList = expandedGroupMetadataList;
refreshExpGroupMetadataList(true, false);
}
@Override
public boolean isEmpty() {
ExpandableListAdapter adapter = getAdapter();
return adapter != null ? adapter.isEmpty() : true;
}
/**
* Searches the expandable list adapter for a group position matching the
* given group ID. The search starts at the given seed position and then
* alternates between moving up and moving down until 1) we find the right
* position, or 2) we run out of time, or 3) we have looked at every
* position
*
* @return Position of the row that matches the given row ID, or
* {@link AdapterView#INVALID_POSITION} if it can't be found
* @see AdapterView#findSyncPosition()
*/
int findGroupPosition(long groupIdToMatch, int seedGroupPosition) {
int count = mExpandableListAdapter.getGroupCount();
if (count == 0) {
return AdapterView.INVALID_POSITION;
}
// If there isn't a selection don't hunt for it
if (groupIdToMatch == AdapterView.INVALID_ROW_ID) {
return AdapterView.INVALID_POSITION;
}
// Pin seed to reasonable values
seedGroupPosition = Math.max(0, seedGroupPosition);
seedGroupPosition = Math.min(count - 1, seedGroupPosition);
long endTime = SystemClock.uptimeMillis() + AdapterView.SYNC_MAX_DURATION_MILLIS;
long rowId;
// first position scanned so far
int first = seedGroupPosition;
// last position scanned so far
int last = seedGroupPosition;
// True if we should move down on the next iteration
boolean next = false;
// True when we have looked at the first item in the data
boolean hitFirst;
// True when we have looked at the last item in the data
boolean hitLast;
// Get the item ID locally (instead of getItemIdAtPosition), so
// we need the adapter
ExpandableListAdapter adapter = getAdapter();
if (adapter == null) {
return AdapterView.INVALID_POSITION;
}
while (SystemClock.uptimeMillis() <= endTime) {
rowId = adapter.getGroupId(seedGroupPosition);
if (rowId == groupIdToMatch) {
// Found it!
return seedGroupPosition;
}
hitLast = last == count - 1;
hitFirst = first == 0;
if (hitLast && hitFirst) {
// Looked at everything
break;
}
if (hitFirst || (next && !hitLast)) {
// Either we hit the top, or we are trying to move down
last++;
seedGroupPosition = last;
// Try going up next time
next = false;
} else if (hitLast || (!next && !hitFirst)) {
// Either we hit the bottom, or we are trying to move up
first--;
seedGroupPosition = first;
// Try going down next time
next = true;
}
}
return AdapterView.INVALID_POSITION;
}
protected class MyDataSetObserver extends DataSetObserver {
@Override
public void onChanged() {
refreshExpGroupMetadataList(true, true);
notifyDataSetChanged();
}
@Override
public void onInvalidated() {
refreshExpGroupMetadataList(true, true);
notifyDataSetInvalidated();
}
}
/**
* Metadata about an expanded group to help convert from a flat list
* position to either a) group position for groups, or b) child position for
* children
*/
static class GroupMetadata implements Parcelable, Comparable<GroupMetadata> {
final static int REFRESH = -1;
/** This group's flat list position */
int flPos;
/* firstChildFlPos isn't needed since it's (flPos + 1) */
/**
* This group's last child's flat list position, so basically
* the range of this group in the flat list
*/
int lastChildFlPos;
/**
* This group's group position
*/
int gPos;
/**
* This group's id
*/
long gId;
private GroupMetadata() {
}
static GroupMetadata obtain(int flPos, int lastChildFlPos, int gPos, long gId) {
GroupMetadata gm = new GroupMetadata();
gm.flPos = flPos;
gm.lastChildFlPos = lastChildFlPos;
gm.gPos = gPos;
gm.gId = gId;
return gm;
}
public int compareTo(GroupMetadata another) {
if (another == null) {
throw new IllegalArgumentException();
}
return gPos - another.gPos;
}
public int describeContents() {
return 0;
}
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(flPos);
dest.writeInt(lastChildFlPos);
dest.writeInt(gPos);
dest.writeLong(gId);
}
public static final Parcelable.Creator<GroupMetadata> CREATOR =
new Parcelable.Creator<GroupMetadata>() {
public GroupMetadata createFromParcel(Parcel in) {
GroupMetadata gm = GroupMetadata.obtain(
in.readInt(),
in.readInt(),
in.readInt(),
in.readLong());
return gm;
}
public GroupMetadata[] newArray(int size) {
return new GroupMetadata[size];
}
};
}
/**
* Data type that contains an expandable list position (can refer to either a group
* or child) and some extra information regarding referred item (such as
* where to insert into the flat list, etc.)
*/
static public class PositionMetadata {
private static final int MAX_POOL_SIZE = 5;
private static ArrayList<PositionMetadata> sPool =
new ArrayList<PositionMetadata>(MAX_POOL_SIZE);
/** Data type to hold the position and its type (child/group) */
public ExpandableListPosition position;
/**
* Link back to the expanded GroupMetadata for this group. Useful for
* removing the group from the list of expanded groups inside the
* connector when we collapse the group, and also as a check to see if
* the group was expanded or collapsed (this will be null if the group
* is collapsed since we don't keep that group's metadata)
*/
public GroupMetadata groupMetadata;
/**
* For groups that are collapsed, we use this as the index (in
* mExpGroupMetadataList) to insert this group when we are expanding
* this group.
*/
public int groupInsertIndex;
private void resetState() {
position = null;
groupMetadata = null;
groupInsertIndex = 0;
}
/**
* Use {@link #obtain(int, int, int, int, GroupMetadata, int)}
*/
private PositionMetadata() {
}
static PositionMetadata obtain(int flatListPos, int type, int groupPos,
int childPos, GroupMetadata groupMetadata, int groupInsertIndex) {
PositionMetadata pm = getRecycledOrCreate();
pm.position = ExpandableListPosition.obtain(type, groupPos, childPos, flatListPos);
pm.groupMetadata = groupMetadata;
pm.groupInsertIndex = groupInsertIndex;
return pm;
}
private static PositionMetadata getRecycledOrCreate() {
PositionMetadata pm;
synchronized (sPool) {
if (sPool.size() > 0) {
pm = sPool.remove(0);
} else {
return new PositionMetadata();
}
}
pm.resetState();
return pm;
}
public void recycle() {
synchronized (sPool) {
if (sPool.size() < MAX_POOL_SIZE) {
sPool.add(this);
}
}
}
/**
* Checks whether the group referred to in this object is expanded,
* or not (at the time this object was created)
*
* @return whether the group at groupPos is expanded or not
*/
public boolean isExpanded() {
return groupMetadata != null;
}
}
}
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