stop scrollView in the middle of the scroll

One approach may be to use smoothScrollToPosition, which stops any existing scrolling motion. Note this method requires API level >= 8 (Android 2.2, Froyo).

Note that if the current position is far away from the desired position, then the smooth scrolling will take quite a long time and look a bit jerky (at least in my testing on Android 4.4 KitKat). I also found that a combination of calling setSelection and smoothScrollToPosition could sometimes causes the position to "miss" slightly, this seems to happen only when the current position was very close to the desired position.

In my case, I wanted my list to jump to the top (position=0) when the user pressed a button (this is slightly different from your use case, so you will need to adapt this to your needs).

I used the following method to

private void smartScrollToPosition(ListView listView, int desiredPosition) {
    // If we are far away from the desired position, jump closer and then smooth scroll
    // Note: we implement this ourselves because smoothScrollToPositionFromTop
    // requires API 11, and it is slow and janky if the scroll distance is large,
    // and smoothScrollToPosition takes too long if the scroll distance is large.
    // Jumping close and scrolling the remaining distance gives a good compromise.
    int currentPosition = listView.getFirstVisiblePosition();
    int maxScrollDistance = 10;
    if (currentPosition - desiredPosition >= maxScrollDistance) {
        listView.setSelection(desiredPosition + maxScrollDistance);
    } else if (desiredPosition - currentPosition >= maxScrollDistance) {
        listView.setSelection(desiredPosition - maxScrollDistance);
    }
    listView.smoothScrollToPosition(desiredPosition); // requires API 8
}

In my action handler for the button I then called this as follows

    case R.id.action_go_to_today:
        ListView listView = (ListView) findViewById(R.id.lessonsListView);
        smartScrollToPosition(listView, 0); // scroll to top
        return true;

The above does not directly answer your question, but if you can detect when the current position is at or near your desired position, then maybe you could use smoothScrollToPosition to stop the scrolling.

To stop a fling at a particular point simply call

fling(0)

If you are only concerned about flings this is the most logical way to do so in my opinion, because velosityYis set to 0 and thereby the fling is stopped immediately.

Here is the javadoc of the fling method:

/**
 * Fling the scroll view
 *
 * @param velocityY The initial velocity in the Y direction. Positive
 *                  numbers mean that the finger/cursor is moving down the screen,
 *                  which means we want to scroll towards the top.
 */

I had the same problem my solution was.

listView.smoothScrollBy(0,0)

This will stop the scrolling.