Why does calling getWidth() on a View in onResume() return 0?

Question

Everything I\'ve read says you can\'t call getWidth() or getHeight() on a View in a constructor, but I\'m calling them in onResu

Answer 1

A view still hasn't been drawn when onResume() is called, so its width and height are 0. You can "catch" when its size changes using OnGlobalLayoutListener():

yourView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

    @Override
    public void onGlobalLayout() {

        // Removing layout listener to avoid multiple calls
        if(Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
            yourView.getViewTreeObserver().removeGlobalOnLayoutListener(this);
        }
        else {
            yourView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
        }

        populateData();
    }
});

For additional info take a look at Android get width returns 0.