private void applyPadding(int padding, final View[] targetViews) {
        for (View view : targetViews) view.setPadding(padding, padding, padding, padding);
    }
Sets the padding to be used for the number pad buttons.

@param padding padding in pixels
android/third_party/time-duration-picker/src/main/java/mobi/upod/timedurationpicker/TimeDurationPicker.java