Android 自定义view 不执行 ondraw的解决办法

Android 自定义view 不执行 ondraw的解决办法

Android 自定义view 不执行 ondraw的解决办法

1. public class BackgroundLayout extends LinearLayout {  
2.   
3.               public BackgroundLayout(Context context, int position) {  
4.                       super(context);  
5.                     <span style="color:#ff0000;">  setWillNotDraw</span>(false);  
6.   
7.               }  
8.   
9.               @Override  
10.               protected void onDraw(Canvas canvas) {  
11.                      super.onDraw(canvas);  
12.   
13.               }  
14.   
15.       }  

出现这种情况大多是继承自layout。在构造方法中添加 setWillNotDraw 问题解决。

相关解释如下

If this view doesn't do any drawing on its own, set this flag to allow further optimizations. By default, this flag is not set on View, but

 could be set on some View subclasses such as ViewGroup. Typically, if you override onDraw(Canvas) you should clear this flag.