How to check whether ScrollView is scrollable

Question

I was wondering, how to check whether the current ScrollView is scrollable? It seems that, there isn\'t public method called canScroll or isS

Answer 1

scrollView.viewTreeObserver
        .addOnGlobalLayoutListener {

            val isScrollable = scrollView.canScrollVertically(1)
        }

Answer 2

You can do some little math to calculate the views raw height and the height of the content. If the difference of this heights is < 0 the view is scrollable.

To calculate the raw height you can use View.getMeasuredHeight(). Because ScrollView is a ViewGroup and has max one child, get the height of that child with ViewGroup.getChildAt(0).getHeight();

Use a ViewTreeObserver to get the heights, because it will be called at the moment the layout / view is changing the visibility, otherwise the heights could be 0.

ScrollView scrollView = (ScrollView)findViewById(R.id...);
ViewTreeObserver observer = scrollView.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        int viewHeight = scrollView.getMeasuredHeight();
        int contentHeight = scrollView.getChildAt(0).getHeight();
        if(viewHeight - contentHeight < 0) {
            // scrollable
        }
    }
});

Answer 3

I think I might be missing something, but shouldn't it be as simple as checking if

scrollView.getHeight() >= parentView.getMeasuredHeight()

you might actually need: scrollView.getChildAt(0).getHeight() and/or parentView.getHeight() instead, but the idea is the same.