android - How to check if a my ListView has scrollable number of items?

Question

How do you know if your ListView has enough number of items so that it can scroll?

For instance, If I have 5 items on my ListView all of it will be displayed on a single screen. But if I have 7 or more, my ListView begins to scroll. How do I know if my List can scroll programmatically?

Answer 1

Diegosan's answer cannot differentiate when the last item is partially visible on the screen. Here is a solution to that problem.

First, the ListView must be rendered on the screen before we can check if its content is scrollable. This can be done with a ViewTreeObserver:

ViewTreeObserver observer = listView.getViewTreeObserver();
    observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

        @Override
        public void onGlobalLayout() {
            if (willMyListScroll()) {
                 // Do something
            } 
        }
    });

And here is willMyListScroll():

boolean willMyListScroll() {   
    int pos = listView.getLastVisiblePosition();
    if (listView.getChildAt(pos).getBottom() > listView.getHeight()) {
        return true;
    } else {
        return false;
    }
}