获得实际的视图高度

TextView textView = (TextView)findViewById(R.id.my_textview);
ViewTreeObserver observer = textView.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        //in here, place the code that requires you to know the dimensions.
        //this will be called as the layout is finished, prior to displaying.
    }
}

ViewTreeObserver observer = this.findViewById(android.R.id.content).getViewTreeObserver();