爲什麼view.getHeigth在onResume（）上返回0？

Question

它是我的代碼。 referButtun是的ImageButton

@Override 
protected void onResume() { 
    super.onResume(); 
    referButtun.getHeight(); 
    Log.d("Base",""+referButtun.getHeight()); 
} 

Answer 1

這就是你應該怎麼做：

final ViewTreeObserver vto = referButtun.getViewTreeObserver(); 
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() { 
    @Override 
    public void onGlobalLayout() { 
     Log.d("Base",""+referButtun.getHeight()); 

     // don't forget to remove the listener, we don't need it just this one time 
     vto.removeGlobalOnLayoutListener(this); 
    } 
}); 

作爲替代，你可以使用

referButtun.post(new Runnable() { 
    @Override 
    public void run() { 
     Log.d("Base",""+referButtun.getHeight()); 
    } 
});