I am trying to implement AsyncQueryHandler because I am experiencing the same exact problem in this link but I dont see any example or anything about implementing it.
I tried doing
AsyncQueryHandler handler = new AsyncQueryHandler(getContentResolver());
since that is what the constructor shows in the docs but I get an error saying cannot instantiate the type AsyncQueryHandler so how do I use it then?
It's so convenient:
AsyncQueryHandler handler =
new AsyncQueryHandler(mActivity.getContentResolver()) {};
handler.startUpdate(-1, null, sessionUri, values, null, null);
This Handler class should be static or leaks might occurIt comes very handy when you need to do CRUD operationa async without using a Loader, so by extending from asyncquery you get method such as startQuery, startInsert, startUpdate and startDelete an easy implementation could be:
public class CustomAsyncHandler extends AsyncQueryHandler {
private WeakReference<AsyncQueryListener> mListener;
public interface AsyncQueryListener {
void onQueryComplete(int token, Object cookie, Cursor cursor);
}
public CustomAsyncHandler(ContentResolver cr, AsyncQueryListener listener) {
super(cr);
mListener = new WeakReference<AsyncQueryListener>(listener);
}
public CustomAsyncHandler(ContentResolver cr) {
super(cr);
}
/**
* Assign the given {@link AsyncQueryListener} to receive query events from
* asynchronous calls. Will replace any existing listener.
*/
public void setQueryListener(AsyncQueryListener listener) {
mListener = new WeakReference<AsyncQueryListener>(listener);
}
/** {@inheritDoc} */
@Override
protected void onQueryComplete(int token, Object cookie, Cursor cursor) {
final AsyncQueryListener listener = mListener.get();
if (listener != null) {
listener.onQueryComplete(token, cookie, cursor);
} else if (cursor != null) {
cursor.close();
}
}
}
As you can see there is an extra interface AsyncQueryListener created to be as a callback when query is completed, as this you can create AsyncUpdateListener, AsyncDeleteListener, AsyncInsertListener, and so on.
AsyncQueryHandler is an abstract class, thus you cannot instantiate it directly. You need to subclass it.
AsyncQueryHandler asyncQueryHandler = new AsyncQueryHandler(activity.getContentResolver()){
@Override
protected void onInsertComplete(int token, Object cookie, Uri uri) {
super.onInsertComplete(token, cookie, uri);
Log.d(TAG, "onInsertComplete return uri: " + uri);
}
};
asyncQueryHandler.startInsert(-1, null, mUri, values);
