QueryLoader closing previous result even if it's the same result

[gregkorossy]

Here are two methods of QueryLoader:

@Override
protected void onStartLoading() {
    if (result != null) {
        deliverResult(result);
    } else {
        forceLoad();
    }
}

@Override
public void deliverResult(Result<E> data) {
    if (isReset()) {
        if (result != null) {
            result.close();
        }
        return;
    }
    Result<E> previous = result;
    result = data;
    if (isStarted()) {
        super.deliverResult(result);
    }
    if (previous != null) {
        previous.close();
    }
}

As it is a Loader, it tries to use the previous results if available (onStartLoading()'s deliverResult(result);). This is cool, but the problem is that deliverResult(...) does not check whether the previous result is the same as the new one, and closes it anyway. This results in IllegalStateException when trying to use the same result again as it has been closed.

There's a quick fix for the problem in deliverResult(...), instead of

if (previous != null) {
    previous.close();
}

it should check whether the previous and current results are different objects:

if (previous != null && previous != data) {
    previous.close();
}

[npurushe]

Thanks for the detailed bug report, yes that looks like the correct fix will update thanks