布局很简单,代码就是打个日志看看,为了不影响阅读,放在最后 Android事件处理机制真是个磨人的小妖精,被她卡过两次,一卡住就不行玩安卓,跑过去玩html、js、css了 最好自己动手测试一下,印象更深
点击:ViewGroup1(最外层)
I/System.out: MainActivity dispatchTouchEvent I/System.out: ViewGroup1 dispatchTouchEvent ViewGroup1 onInterceptTouchEvent I/System.out: ViewGroup1 onTouchEvent MainActivity onTouchEvent I/System.out: MainActivity dispatchTouchEvent MainActivity onTouchEvent 点击ViewGroup 1.png点击:ViewGroup2(中间层)
I/System.out: MainActivity dispatchTouchEvent ViewGroup1 dispatchTouchEvent ViewGroup1 onInterceptTouchEvent ViewGroup2 dispatchTouchEvent ViewGroup2 onInterceptTouchEvent ViewGroup2 onTouchEvent ViewGroup1 onTouchEvent MainActivity onTouchEvent I/System.out: MainActivity dispatchTouchEvent MainActivity onTouchEvent 点击ViewGroup 2.png点击:View1
I/System.out: MainActivity dispatchTouchEvent I/System.out: ViewGroup1 dispatchTouchEvent ViewGroup1 onInterceptTouchEvent ViewGroup2 dispatchTouchEvent ViewGroup2 onInterceptTouchEvent View1 dispatchTouchEvent View1 onTouchEvent ViewGroup2 onTouchEvent ViewGroup1 onTouchEvent MainActivity onTouchEvent I/System.out: MainActivity dispatchTouchEvent MainActivity onTouchEvent 点击View.png苹果树上掉下(分发:dispatchTouchEvent false)个苹果(event),爷爷(ViewGroup1)拿到。 爷爷如果不分发(dispatchTouchEvent true)了,相当于把苹果扔了,谁都不吃,包括他自己 他如果截断(onInterceptTouchEvent true),自己可以把苹果吃了(执行onTouchEvent 并返回true),也可以不吃(flase),但只要截断,就不会再向下传了。
点击ViewGroup.png dispatchTouchEvent:决定了事件是否继续分发下去和是否响应事件 false:继续分发, true:不继续分发--此次事件到此结束,也不会有任何控件执行onTouchEvent方法。 onInterceptTouchEvent:决定了是否拦截该事件 false:不拦截 true:拦截---此时当前控件执行onTouchEvent方法。 onTouchEvent:决定了是否消费该事件 false:不消费 true:消费。二、事件处理机制对view.setOnClickListener的影响
对于View1来说:setOnClickListener: 能执行必须前面的分发,不截断,畅通无阻, 并且自己的onTouchEvent返回super.onTouchEvent(event),有一个环节出现意外都无法触发
对于ViewGroup2(也就是View1的父容器),所有均默认,如果View1的onTouchEvent返回false 则点击View1的时候ViewGroup2的setOnClickListener会触发。
所以来看setOnClickListener的触发条件还是蛮苛刻的。
三、View的几个生命函数的调用顺序
用一个ViewGroup3,包裹View2和View3两个View,进行测试,详情看图
ViewGroup.pngView1
public class View1 extends View { public View1(Context context) { super(context); } public View1(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public View1(Context context, AttributeSet attrs) { super(context, attrs); } @Override public boolean dispatchTouchEvent(MotionEvent event) { System.out.println(getClass().getSimpleName() + " dispatchTouchEvent:" ); return super.dispatchTouchEvent(event); } @Override public boolean onTouchEvent(MotionEvent event) { System.out.println(getClass().getSimpleName() + " onTouchEvent:" ); return super.onTouchEvent(event); } }ViewGroup1
public class ViewGroup1 extends LinearLayout { public ViewGroup1(Context context) { super(context); } public ViewGroup1(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public ViewGroup1(Context context, AttributeSet attrs) { super(context, attrs); } @Override public boolean dispatchTouchEvent(MotionEvent ev) { System.out.println(getClass().getSimpleName() + " dispatchTouchEvent:" ); return super.dispatchTouchEvent(ev); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { System.out.println(getClass().getSimpleName() + " onInterceptTouchEvent:"); return super.onInterceptTouchEvent(ev); } @Override public boolean onTouchEvent(MotionEvent event) { System.out.println(getClass().getSimpleName() + " onTouchEvent:" ); return super.onTouchEvent(event); } }ViewGroup2
public class ViewGroup2 extends LinearLayout { public ViewGroup2(Context context) { super(context); } public ViewGroup2(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public ViewGroup2(Context context, AttributeSet attrs) { super(context, attrs); } @Override public boolean dispatchTouchEvent(MotionEvent ev) { System.out.println(getClass().getSimpleName() + " dispatchTouchEvent:" ); return super.dispatchTouchEvent(ev); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { System.out.println(getClass().getSimpleName() + " onInterceptTouchEvent:" ); return super.onInterceptTouchEvent(ev); } @Override public boolean onTouchEvent(MotionEvent event) { System.out.println(getClass().getSimpleName() + " onTouchEvent:"); return super.onTouchEvent(event); } }布局:
<com.toly1994.d.event.ViewGroup1 android:id="@+id/vg1" xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center" android:orientation="vertical"> <com.toly1994.d.event.ViewGroup2 android:id="@+id/vg2" android:layout_width="@dimen/dp_200" android:layout_height="@dimen/dp_200" android:background="@android:color/darker_gray" android:orientation="vertical" android:padding="20dp"> <com.toly1994.d.event.View1 android:id="@+id/v1" android:layout_width="100dp" android:layout_height="100dp" android:background="@android:color/white" android:gravity="center" android:padding="20dp" android:text="me is textview"/> </com.toly1994.d.event.ViewGroup2> </com.toly1994.d.event.ViewGroup1>View2
public class View2 extends View { public View2(Context context) { super(context); } public View2(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public View2(Context context, AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); System.out.println(getClass().getSimpleName() + " onMeasure:" ); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); System.out.println(getClass().getSimpleName() + " onSizeChanged:" ); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); System.out.println(getClass().getSimpleName() + " onLayout:" ); } @Override protected void onFinishInflate() { super.onFinishInflate(); System.out.println(getClass().getSimpleName() + " onFinishInflate:" ); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); System.out.println(getClass().getSimpleName() + " onDraw:" ); } }View3
public class View3 extends View { public View3(Context context) { super(context); } public View3(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public View3(Context context, AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); System.out.println(getClass().getSimpleName() + " onMeasure:" ); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); System.out.println(getClass().getSimpleName() + " onSizeChanged:" ); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); System.out.println(getClass().getSimpleName() + " onLayout:" ); } @Override protected void onFinishInflate() { super.onFinishInflate(); System.out.println(getClass().getSimpleName() + " onFinishInflate:" ); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); System.out.println(getClass().getSimpleName() + " onDraw:" ); } }ViewGroup3
public class ViewGroup3 extends LinearLayout { public ViewGroup3(Context context) { super(context); } public ViewGroup3(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public ViewGroup3(Context context, AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); System.out.println(getClass().getSimpleName() + " onMeasure:"); } @Override protected void onFinishInflate() { super.onFinishInflate(); System.out.println(getClass().getSimpleName() + " onFinishInflate:"); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); System.out.println(getClass().getSimpleName() + " onSizeChanged:"); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); System.out.println(getClass().getSimpleName() + " onLayout:"); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); System.out.println(getClass().getSimpleName() + " onDraw:"); } }布局:
<?xml version="1.0" encoding="utf-8"?> <com.toly1994.d.event.ViewGroup3 xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_margin="5dp" android:background="@color/bisque" android:orientation="horizontal"> <com.toly1994.d.event.View2 android:layout_width="100dp" android:layout_height="100dp" android:background="@color/blue_dark"/> <com.toly1994.d.event.View3 android:layout_width="100dp" android:layout_height="100dp" android:background="@color/darkkhaki"/> </com.toly1994.d.event.ViewGroup3>[1]本文由张风捷特烈原创,转载请注明 [2]欢迎广大编程爱好者共同交流 [3]个人能力有限,如有不正之处欢迎大家批评指证,必定虚心改正 [4]你的喜欢与支持将是我最大的动力
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转载于:https://www.cnblogs.com/toly-top/p/9781895.html
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