/**
* Expands the given group with an animation.
*
* @param groupPos The position of the group to expand
* @return Returns true if the group was expanded. False if the group was already expanded.
*/
@SuppressLint("NewApi")
public boolean expandGroupWithAnimation(int groupPos) {
boolean lastGroup = groupPos == adapter.getGroupCount() - 1;
if (lastGroup && Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
return expandGroup(groupPos, true);
}
int groupFlatPos = getFlatListPosition(getPackedPositionForGroup(groupPos));
if (groupFlatPos != -1) {
int childIndex = groupFlatPos - getFirstVisiblePosition();
if (childIndex < getChildCount()) {
// Get the view for the group is it is on screen...
View v = getChildAt(childIndex);
if (v.getBottom() >= getBottom()) {
// If the user is not going to be able to see the animation
// we just expand the group without an animation.
// This resolves the case where getChildView will not be
// called if the children of the group is not on screen
// We need to notify the adapter that the group was expanded
// without it's knowledge
adapter.notifyGroupExpanded(groupPos);
return expandGroup(groupPos);
}
}
}
// Let the adapter know that we are starting the animation...
adapter.startExpandAnimation(groupPos, 0);
// Finally call expandGroup (note that expandGroup will call
// notifyDataSetChanged so we don't need to)
return expandGroup(groupPos);
}
/**
* Collapses the given group with an animation.
*
* @param groupPos The position of the group to collapse
* @return Returns true if the group was collapsed. False if the group was already collapsed.
*/
public boolean collapseGroupWithAnimation(int groupPos) {
int groupFlatPos = getFlatListPosition(getPackedPositionForGroup(groupPos));
if (groupFlatPos != -1) {
int childIndex = groupFlatPos - getFirstVisiblePosition();
if (childIndex >= 0 && childIndex < getChildCount()) {
// Get the view for the group is it is on screen...
View v = getChildAt(childIndex);
if (v.getBottom() >= getBottom()) {
// If the user is not going to be able to see the animation
// we just collapse the group without an animation.
// This resolves the case where getChildView will not be
// called if the children of the group is not on screen
return collapseGroup(groupPos);
}
} else {
// If the group is offscreen, we can just collapse it without an
// animation...
return collapseGroup(groupPos);
}
}
// Get the position of the firstChild visible from the top of the screen
long packedPos = getExpandableListPosition(getFirstVisiblePosition());
int firstChildPos = getPackedPositionChild(packedPos);
int firstGroupPos = getPackedPositionGroup(packedPos);
// If the first visible view on the screen is a child view AND it's a
// child of the group we are trying to collapse, then set that
// as the first child position of the group... see
// {@link #startCollapseAnimation(int, int)} for why this is necessary
firstChildPos = firstChildPos == -1 || firstGroupPos != groupPos ? 0 : firstChildPos;
// Let the adapter know that we are going to start animating the
// collapse animation.
adapter.startCollapseAnimation(groupPos, firstChildPos);
// Force the listview to refresh it's views
adapter.notifyDataSetChanged();
return isGroupExpanded(groupPos);
}
