安卓触摸事件探究

/**
 * 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,
　　　　dispatchTouchEvent返回false
　　　　onInterceptTouchEvent返回false
　　　　onTouchEvent返回false
MyView
　　　　dispatchTouchEvent返回false　　
　　　　onTouchEvent返回false

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

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

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

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

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

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

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

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

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

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