Merge "Fix the crash caused by DialpadView's OnPreDrawListener." am: 5b6d823a

    @Override

    public boolean onPreDraw() {

      if (!shouldAdjustKeySizes()) {

        return true; // Return true to proceed with the current drawing pass.

        // Return true to proceed with the current drawing pass.

        // Note that we must NOT remove this listener here. The fact that we don't need to adjust

        // keys at the moment doesn't mean they won't need adjustments in the future. For example,

        // when DialpadFragment is hidden, all keys are of the same size (0) and nothing needs to be

        // done. Removing the listener will cost us the ability to adjust them when they reappear.

        // It is only safe to remove the listener after adjusting keys for the first time. See the

        // comment below for more details.

        return true;

      }

      adjustKeySizes();

      // After all keys are adjusted for the first time, no more adjustments will be needed during

      // the rest of DialpadView's lifecycle. It is therefore safe to remove this listener.

      // Another important reason for removing the listener is that it can be triggered AFTER a

      // device orientation change but BEFORE DialpadView's onDetachedFromWindow() and

      // onFinishInflate() are called, i.e., the listener will attempt to adjust the layout before

      // it is inflated, which results in a crash.

      getViewTreeObserver().removeOnPreDrawListener(this);

      return false; // Return false to cancel the current drawing pass.

    }