安卓触摸事件探究

参考,http://blog.csdn.net/chunqiuwei/article/details/41084921

/**
 * 第一步，dispatchTouchEvent，
 *          false：结束
 *          true：到onInterceptTouchEvent
 *              第二步：到onInterceptTouchEvent，
 *                  true：到viewGroup的onTouchEvent
 *                  false：到View dispatchTouchEvent
 *                      第三步：View dispatchTouchEvent
 *                          第四步：View onTouchEvent
 *                                true：view消费touch事件，viewGroup不能消费
 *                                false：viewGroup决定是否消费touch事件
 *
 *
 * @param ev
 * @return
 */

例子原型
MyLinearLayout包含一个MyView
情况一,

MyLinearLayout,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent返回false
　　　　onTouchEvent返回false
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回false

结果

03-18 15:26:00.726    6884-6884/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 15:26:00.726    6884-6884/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 15:26:00.726    6884-6884/com.example.myapp E/zyr﹕ B DIS ACTION_DOWN
03-18 15:26:00.726    6884-6884/com.example.myapp E/zyr﹕ B TOU ACTION_DOWN
03-18 15:26:00.726    6884-6884/com.example.myapp D/zyr﹕ A TOU ACTION_DOWN
03-18 15:26:05.396    6884-6884/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 15:26:05.396    6884-6884/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 15:26:05.396    6884-6884/com.example.myapp E/zyr﹕ B DIS ACTION_DOWN
03-18 15:26:05.396    6884-6884/com.example.myapp E/zyr﹕ B TOU ACTION_DOWN
03-18 15:26:05.396    6884-6884/com.example.myapp D/zyr﹕ A TOU ACTION_DOWN

结论

由图,没有view消费本次触摸事件,Action_Move事件根本传递不进来

情况二,

MyLinearLayout,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent返回false
　　　　onTouchEvent返回false
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回true

结果

03-18 15:36:33.641  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 15:36:33.641  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 15:36:33.641  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_DOWN
03-18 15:36:33.641  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_DOWN
03-18 15:36:33.676  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:36:33.676  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:36:33.676  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:36:33.676  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:36:33.691  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:36:33.691  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:36:33.691  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:36:33.691  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:36:33.711  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:36:33.711  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:36:33.711  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:36:33.711  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:36:33.721  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:36:33.721  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:36:33.721  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:36:33.721  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:36:33.721  10292-10292/com.example.myapp D/zyr﹕ A DIS ACTION_UP
03-18 15:36:33.721  10292-10292/com.example.myapp D/zyr﹕ A INT ACTION_UP
03-18 15:36:33.721  10292-10292/com.example.myapp E/zyr﹕ B DIS ACTION_UP
03-18 15:36:33.721  10292-10292/com.example.myapp E/zyr﹕ B TOU ACTION_UP

结论

MyView消费ACTION_DOWN,之后ACTION_MOVE传递进来,消费ACTION_MOVE,ACTION_UP同理

 情况三,

MyLinearLayout,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent返回false
　　　　onTouchEvent返回true
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回true

结果

03-18 15:40:18.056  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 15:40:18.056  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 15:40:18.056  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_DOWN
03-18 15:40:18.056  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_DOWN
03-18 15:40:18.076  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:40:18.076  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:40:18.076  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:40:18.076  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:40:18.096  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:40:18.096  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:40:18.096  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:40:18.096  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:40:18.111  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:40:18.111  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:40:18.111  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:40:18.111  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:40:18.126  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 15:40:18.126  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 15:40:18.126  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_MOVE
03-18 15:40:18.126  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_MOVE
03-18 15:40:18.131  29163-29163/com.example.myapp D/zyr﹕ A DIS ACTION_UP
03-18 15:40:18.131  29163-29163/com.example.myapp D/zyr﹕ A INT ACTION_UP
03-18 15:40:18.131  29163-29163/com.example.myapp E/zyr﹕ B DIS ACTION_UP
03-18 15:40:18.131  29163-29163/com.example.myapp E/zyr﹕ B TOU ACTION_UP

结论

虽然MyLinearLayout的onTouch返回true,但是MyTouch也是返回true,由于安卓触摸事件传递是由上而下,但是消费触摸事件是由下而上的,所以处于下面的MyView消费掉了触摸事件,MyLinearLayout无法消费

情况四,

研究onInterceptTouchEvent

MyLinearLayout,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent返回true
　　　　onTouchEvent返回false
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回true

结果

03-18 15:44:37.701  20477-20477/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 15:44:37.701  20477-20477/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 15:44:37.701  20477-20477/com.example.myapp D/zyr﹕ A TOU ACTION_DOWN

结论

 

虽然MyView的onTouch返回true,但是被MyLinearLayout拦截下来了(MyLinearLayout的onInterceptTouchEvent返回true),但是MyLinearLayout的onTouch返回false,即它并没有消费此次触摸事件,so,,,此次触摸事件就此结束,当然Action_Move是没有机会传递拉.

情况五,

MyLinearLayout,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent
                       ACTION_DOWN,false
                       ACTION_MOVE,true
                       ACTION_UP,false
　　　　onTouchEvent
                       ACTION_DOWN,false
                       ACTION_MOVE,true
                       ACTION_UP,false
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回true    

结果

03-18 16:09:36.241    8257-8257/com.example.myapp D/zyr﹕ A DIS ACTION_DOWN
03-18 16:09:36.241    8257-8257/com.example.myapp D/zyr﹕ A INT ACTION_DOWN
03-18 16:09:36.241    8257-8257/com.example.myapp E/zyr﹕ B DIS ACTION_DOWN
03-18 16:09:36.241    8257-8257/com.example.myapp E/zyr﹕ B TOU ACTION_DOWN
03-18 16:09:36.271    8257-8257/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 16:09:36.271    8257-8257/com.example.myapp D/zyr﹕ A INT ACTION_MOVE
03-18 16:09:36.296    8257-8257/com.example.myapp D/zyr﹕ A DIS ACTION_MOVE
03-18 16:09:36.296    8257-8257/com.example.myapp D/zyr﹕ A TOU ACTION_MOVE
03-18 16:09:36.296    8257-8257/com.example.myapp D/zyr﹕ A DIS ACTION_UP
03-18 16:09:36.296    8257-8257/com.example.myapp D/zyr﹕ A TOU ACTION_UP

结论

试着自己分析把.