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Android onTouch事件传递机制

2014-07-29 11:56 543 查看
android onTouch事件的传递对于新手来说很可能 不太注意,但是如果我们想要做一些像复合复杂的UI界面的时候, 那么 界面的 触摸事件 处理不好的话,结果就会达不到我们预期的 效果,所以onTouch 事件处理的好,有助于我们做出更优的性能UI. 下面我们来看看onTouch事件的机制是怎样的:

Android的触摸事件:onClick, onScroll, onFling等等,都是由许多个Touch组成的。其中Touch的第一个状态肯定是ACTION_DOWN, 表示按下了屏幕。之后,touch将会有后续事件,可能是:

ACTION_MOVE //表示为移动手势
ACTION_UP //表示为离开屏幕

ACTION_CANCEL //表示取消手势,不会由用户产生,而是由程序产生的

一个Action_DOWN, n个ACTION_MOVE, 1个ACTION_UP,就构成了Android中众多的事件。

在Android中,有一类控件是中还可以包含其他的子控件,这类控件是继承于ViewGroup类,例如:ListView, Gallery, GridView,LinearLayout。

还有一类控件是不能再包含子控件,例如:TextView。

在触发OnTouch事件的时候Android的GroupView会调用如下三个函数:

public boolean dispatchTouchEvent(MotionEvent ev) //用于事件的分发

public boolean onInterceptTouchEvent(MotionEvent ev) // 用于事件的拦截

public boolean onTouchEvent(MotionEvent ev) //处理事件

本文的主要讨论对象就是ViewGroup类的控件嵌套时事件触发情况。

对于ViewGroup类的控件,有一个很重要的方法,就是onInterceptTouchEvent(),用于处理事件并改变事件的传递方向,它的返回值是一个布尔值,决定了Touch事件是否要向它包含的子View继续传递,这个方法是从父View向子View传递。而方法onTouchEvent(),用于接收事件并处理,它的返回值也是一个布尔值,决定了事件及后续事件是否继续向上传递,这个方法是从子View向父View传递。touch事件在
onInterceptTouchEvent()和onTouchEvent以及各个childView间的传递机制完全取决于onInterceptTouchEvent()和onTouchEvent()的返回值。返回值为true表示事件被正确接收和处理了,返回值为false表示事件没有被处理,将继续传递下去。

ACTION_DOWN事件会传到某个ViewGroup类的onInterceptTouchEvent,如果返回false,则DOWN事件继续向子ViewGroup类的onInterceptTouchEvent传递,如果子View不是ViewGroup类的控件,则传递给它的onTouchEvent。

如果onInterceptTouchEvent返回了true,则DOWN事件传递给它的onTouchEvent,不再继续传递,并且之后的后续事件也都传递给它的onTouchEvent。

如果某View的onTouchEvent返回了false,则DOWN事件继续向其父ViewGroup类的onTouchEvent传递;如果返回了true,则后续事件会直接传递给其onTouchEvent继续处理。(后续事件只会传递给对于必要事件ACTION_DOWN返回了true的onTouchEvent。

onInterceptTouchEvent()用于处理事件并改变事件的传递方向。处理事件这个不用说了,你在函数内部编写代码处理就可以了。而决定传递方向的是返回值,返回为false时事件会传递给子控件的onInterceptTouchEvent();返回值为true时事件会传递给当前控件的onTouchEvent(),而不在传递给子控件,这就是所谓的Intercept(截断)。

onTouchEvent() 用于处理事件,返回值决定当前控件是否消费(consume)了这个事件。可能你要问是否消费了又区别吗,反正我已经针对事件编写了处理代码?答案是有区别!比如ACTION_MOVE或者ACTION_UP发生的前提是一定曾经发生了ACTION_DOWN,如果你没有消费ACTION_DOWN,那么系统会认为ACTION_DOWN没有发生过,所以ACTION_MOVE或者ACTION_UP就不能被捕获。

在没有重写onInterceptTouchEvent()和onTouchEvent()的情况下(他们的返回值都是false),即处理事件的返回值默认:false。

代码如下:

MyLinearLayout1.java:

package com.example.my_ontouch;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ViewGroup;
import android.widget.LinearLayout;

public class MyLinearLayout1 extends LinearLayout {

public MyLinearLayout1(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub

switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout1---- dispatchTouchEvent action:ACTION_CANCEL");
break;

default:
break;
}
//		return super.dispatchTouchEvent(ev);
return true;

}

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout1---- onInterceptTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout1---- onInterceptTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}
//		return super.onInterceptTouchEvent(ev);
return true;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout1---- onTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout1---- onTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout1---- onTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout1---- onTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}
return super.onTouchEvent(event);
//		return true;
}

}


MyLinearLayout2.java:

package com.example.my_ontouch;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.LinearLayout;

public class MyLinearLayout2 extends LinearLayout {

public MyLinearLayout2(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub

switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout2---- dispatchTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout2---- dispatchTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}

return super.dispatchTouchEvent(ev);
//		return true;
}

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout2---- onInterceptTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout2---- onInterceptTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout2---- onInterceptTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}
return super.onInterceptTouchEvent(ev);
//		return true;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyLinearLayout2---- onTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyLinearLayout2---- onTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyLinearLayout2---- onTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyLinearLayout2---- onTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}
return super.onTouchEvent(event);
//		return true;
}

}


MyTextView.java:

package com.example.my_ontouch;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.TextView;

public class MyTextView extends TextView {

public MyTextView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub

switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyTextView---- dispatchTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyTextView---- dispatchTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyTextView---- dispatchTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyTextView---- dispatchTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}

return super.dispatchTouchEvent(ev);
//		return true;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Log.e("Test","MyTextView---- onTouchEvent action:ACTION_DOWN");
break;
case MotionEvent.ACTION_MOVE:
Log.e("Test","MyTextView---- onTouchEvent action:ACTION_MOVE");
break;
case MotionEvent.ACTION_UP:
Log.e("Test","MyTextView---- onTouchEvent action:ACTION_UP");
break;
case MotionEvent.ACTION_CANCEL :
Log.e("Test","MyTextView---- onTouchEvent action:ACTION_CANCEL");
break;
default:
break;
}
return super.onTouchEvent(event);
//		return true;
}

}


activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<com.example.my_ontouch.MyLinearLayout1 xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<com.example.my_ontouch.MyLinearLayout2
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
android:orientation="vertical" >

<com.example.my_ontouch.MyTextView
android:id="@+id/tv"
android:layout_width="200px"
android:layout_height="200px"
android:background="#FFFFFF"
android:text="MyTextView"
android:textColor="#0000FF"
android:textSize="40sp"
android:textStyle="bold" />
</com.example.my_ontouch.MyLinearLayout2>

</com.example.my_ontouch.MyLinearLayout1>


onTouch事件传递测试:

注: 当点击MyTextView时,程序会先进入到LinearLayout1的dispatchTouchEvent中,这个类必须调用super.dispatchTouchEvent(ev);否则后面的两个方法无法触发,所以发现这个方法根本没有必要重写,因为框架是在
super.dispatchTouchEvent(ev)中来调用onInterceptTouchEvent和onTouchEvent方法的,所以手动的设置dispatchTouchEvent的返回值是无效的,除非你不想让框架触发这两个方法。还有就是基础空间可能会没有onInterceptTouchEvent , 因为他是最底层的控件. 直接就交给了onTouchEvent
来处理了.

测试一:

首先看看 MyLinearLayout1,MyLinearLayout2和MyTextView 的 onInterceptTouchEvent 和 onTouchEvent 为false的情况。打印的Log日志如下:

07-29 09:45:30.826: E/Test(32332): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyTextView---- dispatchTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyTextView---- onTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyLinearLayout2---- onTouchEvent action:ACTION_DOWN
07-29 09:45:30.826: E/Test(32332): MyLinearLayout1---- onTouchEvent action:ACTION_DOWN


测试二:

MyLinearLayout1---- onInterceptTouchEvent      true
MyLinearLayout1---- onTouchEvent

MyLinearLayout2---- onInterceptTouchEvent
MyLinearLayout2---- onTouchEvent

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:16:33.075: E/Test(8423): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:16:33.075: E/Test(8423): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:16:33.075: E/Test(8423): MyLinearLayout1---- onTouchEvent action:ACTION_DOWN


测试三:

MyLinearLayout1---- onInterceptTouchEvent      true
MyLinearLayout1---- onTouchEvent               true

MyLinearLayout2---- onInterceptTouchEvent
MyLinearLayout2---- onTouchEvent

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:19:23.416: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:19:23.417: E/Test(10384): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:19:23.417: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_DOWN
07-29 10:19:23.430: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.432: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.446: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.446: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.461: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.462: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.478: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.478: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.493: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.493: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.508: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.509: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.524: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:19:23.525: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:19:23.532: E/Test(10384): MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP
07-29 10:19:23.533: E/Test(10384): MyLinearLayout1---- onTouchEvent action:ACTION_UP


测试四:

MyLinearLayout1---- onInterceptTouchEvent
MyLinearLayout1---- onTouchEvent               true

MyLinearLayout2---- onInterceptTouchEvent
MyLinearLayout2---- onTouchEvent

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:23:23.113: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:23:23.113: E/Test(10739): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:23:23.113: E/Test(10739): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:23:23.113: E/Test(10739): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:23:23.113: E/Test(10739): MyTextView---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:23:23.114: E/Test(10739): MyTextView---- onTouchEvent action:ACTION_DOWN
07-29 10:23:23.114: E/Test(10739): MyLinearLayout2---- onTouchEvent action:ACTION_DOWN
07-29 10:23:23.114: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_DOWN
07-29 10:23:23.131: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:23:23.131: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:23:23.145: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:23:23.145: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:23:23.160: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:23:23.160: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:23:23.172: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:23:23.172: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_MOVE
07-29 10:23:23.174: E/Test(10739): MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP
07-29 10:23:23.175: E/Test(10739): MyLinearLayout1---- onTouchEvent action:ACTION_UP


测试五:

MyLinearLayout1---- onInterceptTouchEvent
MyLinearLayout1---- onTouchEvent

MyLinearLayout2---- onInterceptTouchEvent  true
MyLinearLayout2---- onTouchEvent

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:32:27.636: E/Test(12540): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:32:27.636: E/Test(12540): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:32:27.636: E/Test(12540): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:32:27.636: E/Test(12540): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:32:27.636: E/Test(12540): MyLinearLayout2---- onTouchEvent action:ACTION_DOWN
07-29 10:32:27.636: E/Test(12540): MyLinearLayout1---- onTouchEvent action:ACTION_DOWN


测试六:

MyLinearLayout1---- onInterceptTouchEvent
MyLinearLayout1---- onTouchEvent

MyLinearLayout2---- onInterceptTouchEvent
MyLinearLayout2---- onTouchEvent           true

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:34:28.649: E/Test(13744): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyTextView---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyTextView---- onTouchEvent action:ACTION_DOWN
07-29 10:34:28.650: E/Test(13744): MyLinearLayout2---- onTouchEvent action:ACTION_DOWN
07-29 10:34:28.674: E/Test(13744): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:34:28.674: E/Test(13744): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE
07-29 10:34:28.675: E/Test(13744): MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:34:28.675: E/Test(13744): MyLinearLayout2---- onTouchEvent action:ACTION_MOVE
07-29 10:34:28.690: E/Test(13744): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:34:28.690: E/Test(13744): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE
07-29 10:34:28.691: E/Test(13744): MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:34:28.691: E/Test(13744): MyLinearLayout2---- onTouchEvent action:ACTION_MOVE
07-29 10:34:28.692: E/Test(13744): MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP
07-29 10:34:28.692: E/Test(13744): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_UP
07-29 10:34:28.692: E/Test(13744): MyLinearLayout2---- dispatchTouchEvent action:ACTION_UP
07-29 10:34:28.692: E/Test(13744): MyLinearLayout2---- onTouchEvent action:ACTION_UP


测试1七:

MyLinearLayout1---- onInterceptTouchEvent
MyLinearLayout1---- onTouchEvent

MyLinearLayout2---- onInterceptTouchEvent  true
MyLinearLayout2---- onTouchEvent           true

MyTextView---- onInterceptTouchEvent
MyTextView---- onTouchEvent

07-29 10:42:09.779: E/Test(14950): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:42:09.779: E/Test(14950): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:42:09.780: E/Test(14950): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 10:42:09.780: E/Test(14950): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 10:42:09.780: E/Test(14950): MyLinearLayout2---- onTouchEvent action:ACTION_DOWN
07-29 10:42:09.784: E/Test(14950): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:42:09.784: E/Test(14950): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE
07-29 10:42:09.784: E/Test(14950): MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:42:09.784: E/Test(14950): MyLinearLayout2---- onTouchEvent action:ACTION_MOVE
07-29 10:42:09.799: E/Test(14950): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:42:09.799: E/Test(14950): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE
07-29 10:42:09.799: E/Test(14950): MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE
07-29 10:42:09.799: E/Test(14950): MyLinearLayout2---- onTouchEvent action:ACTION_MOVE
07-29 10:42:09.800: E/Test(14950): MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP
07-29 10:42:09.800: E/Test(14950): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_UP
07-29 10:42:09.800: E/Test(14950): MyLinearLayout2---- dispatchTouchEvent action:ACTION_UP
07-29 10:42:09.801: E/Test(14950): MyLinearLayout2---- onTouchEvent action:ACTION_UP


测试八:

MyLinearLayout1---- onInterceptTouchEvent
MyLinearLayout1---- onTouchEvent

MyLinearLayout2---- onInterceptTouchEvent
MyLinearLayout2---- onTouchEvent

MyTextView---- onTouchEvent                true

07-29 11:02:48.053: E/Test(20818): MyLinearLayout1---- dispatchTouchEvent action:ACTION_DOWN
07-29 11:02:48.053: E/Test(20818): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_DOWN
07-29 11:02:48.053: E/Test(20818): MyLinearLayout2---- dispatchTouchEvent action:ACTION_DOWN
07-29 11:02:48.053: E/Test(20818): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_DOWN
07-29 11:02:48.054: E/Test(20818): MyTextView---- dispatchTouchEvent action:ACTION_DOWN
07-29 11:02:48.054: E/Test(20818): MyTextView---- onTouchEvent action:ACTION_DOWN
07-29 11:02:48.077: E/Test(20818): MyLinearLayout1---- dispatchTouchEvent action:ACTION_MOVE
07-29 11:02:48.077: E/Test(20818): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_MOVE
07-29 11:02:48.077: E/Test(20818): MyLinearLayout2---- dispatchTouchEvent action:ACTION_MOVE
07-29 11:02:48.077: E/Test(20818): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_MOVE
07-29 11:02:48.077: E/Test(20818): MyTextView---- dispatchTouchEvent action:ACTION_MOVE
07-29 11:02:48.077: E/Test(20818): MyTextView---- onTouchEvent action:ACTION_MOVE
07-29 11:02:48.082: E/Test(20818): MyLinearLayout1---- dispatchTouchEvent action:ACTION_UP
07-29 11:02:48.082: E/Test(20818): MyLinearLayout1---- onInterceptTouchEvent action:ACTION_UP
07-29 11:02:48.082: E/Test(20818): MyLinearLayout2---- dispatchTouchEvent action:ACTION_UP
07-29 11:02:48.082: E/Test(20818): MyLinearLayout2---- onInterceptTouchEvent action:ACTION_UP
07-29 11:02:48.082: E/Test(20818): MyTextView---- dispatchTouchEvent action:ACTION_UP
07-29 11:02:48.082: E/Test(20818): MyTextView---- onTouchEvent action:ACTION_UP


以上的 onInterceptTouchEvent 和 onTouchEvent 的取值 都是 最基本的测试 :

总结:

1. onInterceptTouchEvent 负责 事件的 拦截,onTouchEvent 负责事件的处理。

2. onInterceptTouchEvent 决定事件是否要 继续向下传递给 子View , onTouchEvent 决定事件是否 往上传递给 父View。

3. 事件传递的完整顺序:( 父View1 ) dispatchTouchEvent ------> ( 父View1 ) onInterceptTouchEvent --------> ( 父View2 ) dispatchTouchEvent --------> ( 父View2 ) onInterceptTouchEvent -------> (基础控件) dispatchTouchEvent --------> (基础控件) onTouchEvent -------->
(父View2) onTouchEvent ---------> (父View 1)onTouchEvent

如下图:



如果你多测试几次,细心的 会发现 onIntercepterTouch 在同一个手势行为当中( DOWN, UP , MOVE ) 值执行一次, 而且当 dispatcherOnTouch 设为 true 的时候 ,onIntercpterTouchEvent 和 onTouchEvent不会执行.

4. 总的执行顺序为 由上往下 ,再由下往上( 由父传子,再由子传父 ). 类似于类加载的向上托管机制.

以上就只是我的简单测试,如果 还要继续深入学习的话,还需多找资料.

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