How to limit Dialog's max height?

1. We can make it to play trick in code.

At Dialog's show function, after app has set contentView, we can add a GlobalLayoutListener on decorView's ViewTreeObserver. At the listener, we can check the decorView's height, if over the max height, just truncate it.

 private void resolveAlertDialogHeight() {
         WindowManager wm = (WindowManager) mContext
                 .getSystemService(Context.WINDOW_SERVICE);
         Display display = wm.getDefaultDisplay();

         Point size = new Point();
         display.getSize(size);
         int height = size.y;

         final int maxHeight = (int) (height * 0.68);

         final View decorView = mWindow.getDecorView();
         decorView.getViewTreeObserver().addOnGlobalLayoutListener(
                 new OnGlobalLayoutListener() {
                     @Override
                     public void onGlobalLayout() {
                         int actualHeight = decorView.getMeasuredHeight();

                         WindowManager.LayoutParams l = mWindow.getAttributes();
                         if (actualHeight > maxHeight) {
                             l.height = maxHeight;

                             mWindow.setAttributes(l);
                         }

                         decorView.getViewTreeObserver()
                                 .removeOnGlobalLayoutListener(this);
                     }
                 });
     }

2. Modify windowBackground reference png.

The dot9 png referenced by android:windowBackground attr is the Dialog's background. We can modify this dot9 png, adding extra padding on top and bottom to limit the margin of Alert.