以下のように実装してみた。
public class ExpandableListAdapter extends SimpleCursorTreeAdapter implements LoaderManager.LoaderCallbacks<Cursor> {
private Context mContext;
private LoaderManager mManager;
public ExpandableListAdapter(
Context context, ExpandableListAdapterListener listener, LoaderManager manager, Cursor groupCursor,
int groupLayout, String[] groupFrom, int[] groupTo,
int childLayout, String[] childFrom, int[] childTo) {
super(context, groupCursor, groupLayout, groupFrom, groupTo, childLayout, childFrom, childTo);
mContext = context;
mManager = manager;
}
@Override
protected Cursor getChildrenCursor(Cursor groupCursor) {
final long idGroup = groupCursor.getLong(groupCursor.getColumnIndex("_id"));
Bundle bundle = new Bundle();
bundle.putLong("idGroup", idGroup);
int groupPos = groupCursor.getPosition();
if (mManager.getLoader(groupPos) != null && !mManager.getLoader(groupPos).isReset()) {
mManager.restartLoader(groupPos, bundle, this);
}
else {
mManager.initLoader(groupPos, bundle, this);
}
return null;
}
@Override
public Loader<Cursor> onCreateLoader(int groupPos, Bundle bundle) {
long idGroup = bundle.getLong("idGroup");
return new CursorLoader(
mContext,
Provider.URI,
new String[]{Table.ID, Table.ID_GROUP, Table.TITLE, Table.CONTEXT},
Table.ID_GROUP + " = ?",
new String[]{String.valueOf(idGroup)},
Table.CREATED + " DESC"
);
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
setChildrenCursor(loader.getId(), cursor);
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
}
}
getChildrenCursorでnullを返すとsetChildrenCursorが実行されるまで子要素が消えるのが表示上気になる。あと、getChildrenCursorでnullを返すとAndroid 1.6でクラッシュする。