Activity中
当屏幕有touch事件时，首先调用Activity的dispatchTouchEvent方法
/** * Called to process touch screen events. You can override this to * intercept all touch screen events before they are dispatched to the * window. Be sure to call this implementation for touch screen events * that should be handled normally. * * @param ev The touch screen event. * * @return boolean Return true if this event was consumed. */ public boolean dispatchTouchEvent(MotionEvent ev) { if (ev.getAction() == MotionEvent.ACTION_DOWN) { onUserInteraction(); } if (getWindow().superDispatchTouchEvent(ev)) { return true; } return onTouchEvent(ev); } 只有ACTION_DOWN事件派发时调运了onUserInteraction方法，直接跳进去可以看见是一个空方法。接着往下看
首先分析Activity的attach方法可以发现getWindow()返回的就是PhoneWindow对象（PhoneWindow为抽象Window的实现子类），那就简单了，也就相当于PhoneWindow类的方法，而PhoneWindow类实现于Window抽象类，所以先看下Window类中抽象方法的定义，如下：
<span style="font-size:24px;">/** * Used by custom windows, such as Dialog, to pass the touch screen event * further down the view hierarchy. Application developers should * not need to implement or call this. *用户不需要重写实现的方法，实质也不能，在Activity中没有提供重写的机会，因为Window是以组</span><pre name="code" class="java"><span style="font-size:24px;">*</span><span style="font-family: Arial, Helvetica, sans-serif;"><span style="font-size:18px;">合模式与Activity建立关系的</span></span> */ public abstract boolean superDispatchTouchEvent(MotionEvent event); PhoneWindow里看下Window抽象方法的实现：@Override public boolean superDispatchTouchEvent(MotionEvent event) { return mDecor.superDispatchTouchEvent(event); } 这里出现了mDecor变量，是啥？其实是DecorView的实例，有人会问DecorView又是啥？
在PhoneWindow类里发现，mDecor是DecorView类的实例，同时DecorView是PhoneWindow的内部类。最惊人的发现是DecorView extends FrameLayout implements RootViewSurfaceTaker，看见没有？它是一个真正Activity的root view,它继承了FrameLayout。 不知道大家是不是熟悉Android App开发技巧中关于UI布局优化使用的SDK工具Hierarchy Viewer，打开的时候在最上面会有个DecorView$PhoneWindow的框框
Activity中setContentView时，把我们编写的xmlLayout文件放置在一个id为content的FrameLayout的布局（DecorView）中，这也就是为啥Activity的setContentView方法叫set content view了，就是把我们的xml放入了这个id为content的FrameLayout中
讲完了DecorView，我们在来看看mDecor.superDispatchTouchEvent(event)：
public boolean superDispatchTouchEvent(MotionEvent event) { return super.dispatchTouchEvent(event); }
上面PhoneWindow的superDispatchTouchEvent直接返回了DecorView的superDispatchTouchEvent，而DecorView又是FrameLayout的子类，FrameLayout又是ViewGroup的子类，touch事件就被分发到的我们们定义的xmlLayout布局中。接下来分析ViewGroup的事件分发。
Activity的dispatchTouchEvent方法的if (getWindow().superDispatchTouchEvent(ev))本质执行的是一个ViewGroup的dispatchTouchEvent方法（这个ViewGroup是Activity特有的root view，也就是id为content的FrameLayout布局）
在Activity的触摸屏事件派发中：Activity,PhoneWindow,DecorView,ViewGroup 1,首先会触发Activity的dispatchTouchEvent方法。 2,dispatchTouchEvent方法中如果是ACTION_DOWN的情况下会接着触发onUserInteraction方法。 3,接着在dispatchTouchEvent方法中会通过Activity的root View（id为content的FrameLayout），实质是ViewGroup，通过super.dispatchTouchEvent把touchevent派发给各个activity的子view，也就是我们再Activity.onCreat方法中setContentView时设置的view。 4，若Activity下面的子view拦截了touchevent事件(返回true)则Activity.onTouchEvent方法就不会执行。
ViewGroup中
既然Activity中的DecorView是ViewGroup的子类调用了dispatchTouchEvent方法，来看看这个方法：
@Override public boolean dispatchTouchEvent(MotionEvent ev) { if (mInputEventConsistencyVerifier != null) { mInputEventConsistencyVerifier.onTouchEvent(ev, 1); } // If the event targets the accessibility focused view and this is it, start // normal event dispatch. Maybe a descendant is what will handle the click. if (ev.isTargetAccessibilityFocus() && isAccessibilityFocusedViewOrHost()) { ev.setTargetAccessibilityFocus(false); } boolean handled = false; if (onFilterTouchEventForSecurity(ev)) { final int action = ev.getAction(); final int actionMasked = action & MotionEvent.ACTION_MASK; /*清除以往的Touch状态然后开始新的手势。在这里你会发现cancelAndClearTouchTargets(ev)方法中有一个非常重要的操作就是将mFirstTouchTarget设置为了null（刚开始分析大眼瞄一眼没留意，结果越往下看越迷糊，所以这个是分析ViewGroup的dispatchTouchEvent方法第一步中重点要记住的一个地方），接着在resetTouchState()方法中重置Touch状态标识。*/ // Handle an initial down. if (actionMasked == MotionEvent.ACTION_DOWN) { // Throw away all previous state when starting a new touch gesture. // The framework may have dropped the up or cancel event for the previous gesture // due to an app switch, ANR, or some other state change. cancelAndClearTouchTargets(ev); resetTouchState(); } // Check for interception.检查拦截 final boolean intercepted; if (actionMasked == MotionEvent.ACTION_DOWN || mFirstTouchTarget != null) {// 说明当事件为ACTION_DOWN或者mFirstTouchTarget不为null(即已经找到能够接收touch事件的目标组件)时if成立，否则if不成立，然后将intercepted设置为true，也即拦截事件 final boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0; if (!disallowIntercept) { // 如果没有禁止拦截，就调用onInterceptTouchEvent方法，touch事件就继续传递给子View，默认不拦截 intercepted = onInterceptTouchEvent(ev); ev.setAction(action); // restore action in case it was changed存储动作以防止它改变 } else { intercepted = false; // 如果禁止拦截，intercepted就是false，touch事件就继续传递给子View } } else { // There are no touch targets and this action is not an initial down // so this view group continues to intercept touches.如果没有touch目标组件和down事件，这个viewgroup就是继续拦截touch intercepted = true; } // If intercepted, start normal event dispatch. Also if there is already // a view that is handling the gesture, do normal event dispatch. if (intercepted || mFirstTouchTarget != null) { ev.setTargetAccessibilityFocus(false); } // Check for cancelation.检查取消，然后将结果赋值给局部boolean变量canceled final boolean canceled = resetCancelNextUpFlag(this) || actionMasked == MotionEvent.ACTION_CANCEL; // Update list of touch targets for pointer down, if needed. 默认是true，作用是是否把事件分发给多个子View final boolean split = (mGroupFlags & FLAG_SPLIT_MOTION_EVENTS) != 0; TouchTarget newTouchTarget = null; boolean alreadyDispatchedToNewTouchTarget = false; if (!canceled && !intercepted) { // 如果没有被取消也没有被拦截，就开始进行分发事件了 // If the event is targeting accessiiblity focus we give it to the // view that has accessibility focus and if it does not handle it // we clear the flag and dispatch the event to all children as usual. // We are looking up the accessibility focused host to avoid keeping // state since these events are very rare. View childWithAccessibilityFocus = ev.isTargetAccessibilityFocus() ? findChildWithAccessibilityFocus() : null; if (actionMasked == MotionEvent.ACTION_DOWN || (split && actionMasked == MotionEvent.ACTION_POINTER_DOWN) || actionMasked == MotionEvent.ACTION_HOVER_MOVE) { final int actionIndex = ev.getActionIndex(); // always 0 for down final int idBitsToAssign = split ? 1 << ev.getPointerId(actionIndex) : TouchTarget.ALL_POINTER_IDS; // Clean up earlier touch targets for this pointer id in case they // have become out of sync. removePointersFromTouchTargets(idBitsToAssign); final int childrenCount = mChildrenCount; if (newTouchTarget == null && childrenCount != 0) { // childrenCount个数是否不为0且新的touch target是空，目的就是为了找到touch target final float x = ev.getX(actionIndex); final float y = ev.getY(actionIndex); // Find a child that can receive the event. // Scan children from front to back. final ArrayList<View> preorderedList = buildOrderedChildList();//子View的list集合preorderedList final boolean customOrder = preorderedList == null && isChildrenDrawingOrderEnabled(); final View[] children = mChildren; for (int i = childrenCount - 1; i >= 0; i--) {//for循环i从childrenCount - 1开始遍历到0，倒序遍历所有的子view final int childIndex = customOrder ? getChildDrawingOrder(childrenCount, i) : i; final View child = (preorderedList == null) ? children[childIndex] : preorderedList.get(childIndex); // If there is a view that has accessibility focus we want it // to get the event first and if not handled we will perform a // normal dispatch. We may do a double iteration but this is // safer given the timeframe. if (childWithAccessibilityFocus != null) { if (childWithAccessibilityFocus != child) { continue; } childWithAccessibilityFocus = null; i = childrenCount - 1; } if (!canViewReceivePointerEvents(child) || !isTransformedTouchPointInView(x, y, child, null)) { ev.setTargetAccessibilityFocus(false); continue; } newTouchTarget = getTouchTarget(child); //这一句很重要，通过getTouchTarget去查找当前子View是否在mFirstTouchTarget.next这条target链中的某一个target中，如果在则返回这个target，否则返回null if (newTouchTarget != null) {//找到了接收Touch事件的子View，即newTouchTarget，那么，既然已经找到了，所以执行break跳出for循环 // Child is already receiving touch within its bounds. // Give it the new pointer in addition to the ones it is handling. newTouchTarget.pointerIdBits |= idBitsToAssign; break; } resetCancelNextUpFlag(child); /** *调用方法dispatchTransformedTouchEvent()将Touch事件传递给特定的子View。该方法十分重要，在该方法中为一个递归调用，会递归调用 dispatchTouchEvent()方法。在dispatchTouchEvent()中如果子View为ViewGroup并且Touch没有被拦截那么递归调用dispatchTouchEvent()，如果子View为View那么就会调用其onTouchEvent()。dispatchTransformedTouchEvent方法如果返回true则表示子View消费掉该事件，同时进入该if判断。满足if语句后重要的操作有： 1,给newTouchTarget赋值； 2,给alreadyDispatchedToNewTouchTarget赋值为true； 3,执行break，因为该for循环遍历子View判断哪个子View接受Touch事件，既然已经找到了就跳出该外层for循环； */ if (dispatchTransformedTouchEvent(ev, false, child, idBitsToAssign)) { // Child wants to receive touch within its bounds. mLastTouchDownTime = ev.getDownTime(); if (preorderedList != null) { // childIndex points into presorted list, find original index for (int j = 0; j < childrenCount; j++) { if (children[childIndex] == mChildren[j]) { mLastTouchDownIndex = j; break; } } } else { mLastTouchDownIndex = childIndex; } mLastTouchDownX = ev.getX(); mLastTouchDownY = ev.getY(); newTouchTarget = addTouchTarget(child, idBitsToAssign); alreadyDispatchedToNewTouchTarget = true; break; } // The accessibility focus didn't handle the event, so clear // the flag and do a normal dispatch to all children. ev.setTargetAccessibilityFocus(false); } if (preorderedList != null) preorderedList.clear(); } if (newTouchTarget == null && mFirstTouchTarget != null) { // Did not find a child to receive the event. // Assign the pointer to the least recently added target. newTouchTarget = mFirstTouchTarget; while (newTouchTarget.next != null) { newTouchTarget = newTouchTarget.next; } newTouchTarget.pointerIdBits |= idBitsToAssign; } } } /** *因为在dispatchTransformedTouchEvent()会调用递归调用dispatchTouchEvent()和onTouchEvent()，所以dispatchTransformedTouchEvent()的返回值实际上是由 onTouchEvent()决定的。简单地说onTouchEvent()是否消费了Touch事件的返回值决定了dispatchTransformedTouchEvent()的返回值，从而决定mFirstTouchTarget是否为null，进一步决定了ViewGroup 是否处理Touch事件 */ // Dispatch to touch targets. if (mFirstTouchTarget == null) { // No touch targets so treat this as an ordinary view. handled = dispatchTransformedTouchEvent(ev, canceled, null, TouchTarget.ALL_POINTER_IDS); } else { // Dispatch to touch targets, excluding the new touch target if we already // dispatched to it. Cancel touch targets if necessary. TouchTarget predecessor = null; TouchTarget target = mFirstTouchTarget; while (target != null) { final TouchTarget next = target.next; if (alreadyDispatchedToNewTouchTarget && target == newTouchTarget) { handled = true; } else { final boolean cancelChild = resetCancelNextUpFlag(target.child) || intercepted; if (dispatchTransformedTouchEvent(ev, cancelChild, target.child, target.pointerIdBits)) { handled = true; } if (cancelChild) { if (predecessor == null) { mFirstTouchTarget = next; } else { predecessor.next = next; } target.recycle(); target = next; continue; } } predecessor = target; target = next; } } // Update list of touch targets for pointer up or cancel, if needed. if (canceled || actionMasked == MotionEvent.ACTION_UP || actionMasked == MotionEvent.ACTION_HOVER_MOVE) { resetTouchState(); } else if (split && actionMasked == MotionEvent.ACTION_POINTER_UP) { final int actionIndex = ev.getActionIndex(); final int idBitsToRemove = 1 << ev.getPointerId(actionIndex); removePointersFromTouchTargets(idBitsToRemove); } } if (!handled && mInputEventConsistencyVerifier != null) { mInputEventConsistencyVerifier.onUnhandledEvent(ev, 1); } return handled; } ViewGroup中的onInterceptTouchEvent
/** * Implement this method to intercept all touch screen motion events. This * allows you to watch events as they are dispatched to your children, and * take ownership of the current gesture at any point. *实现这个方法拦截屏幕的所有触摸事件，这就允许你观察这些事件被分发给你的孩子，在任何一个点掌控当前手势 * <p>Using this function takes some care, as it has a fairly complicated * interaction with {@link View#onTouchEvent(MotionEvent) * View.onTouchEvent(MotionEvent)}, and using it requires implementing * that method as well as this one in the correct way. Events will be * received in the following order: *使用这个函数要小心，它和View的onTouchEvent有十分复杂的交互，事件能够按照下列的顺序被收到: * <ol> * <li> You will receive the down event here.1,你将先收到down事件 * <li> The down event will be handled either by a child of this view * group, or given to your own onTouchEvent() method to handle; this means * you should implement onTouchEvent() to return true, so you will * continue to see the rest of the gesture (instead of looking for * a parent view to handle it). Also, by returning true from * onTouchEvent(), you will not receive any following * events in onInterceptTouchEvent() and all touch processing must * happen in onTouchEvent() like normal. * 2，down事件要么被子View的handle,要么被这个viewgroup的onTouchEvent方法处理 * <li> For as long as you return false from this function, each following * event (up to and including the final up) will be delivered first here * and then to the target's onTouchEvent(). * 3，只要onInterceptTouchEvent返回false，后面的每个事件都会继续分发到touch target执行target's onTouchEvent() * <li> If you return true from here, you will not receive any * following events: the target view will receive the same event but * with the action {@link MotionEvent#ACTION_CANCEL}, and all further * events will be delivered to your onTouchEvent() method and no longer * appear here. * 4，onInterceptTouchEvent返回true, 交给这个ViewGroup的onTouchEvent处理。 * </ol> * * @param ev The motion event being dispatched down the hierarchy. * @return Return true to steal motion events from the children and have * them dispatched to this ViewGroup through onTouchEvent(). * The current target will receive an ACTION_CANCEL event, and no further * messages will be delivered here. */ public boolean onInterceptTouchEvent(MotionEvent ev) { return false; } 看到了吧，这个方法算是ViewGroup不同于View特有的一个事件派发调运方法。在源码中可以看到这个方法实现很简单，但是有一堆注释。其实上面分析了，如果ViewGroup的onInterceptTouchEvent返回false就不阻止事件继续传递派发，否则阻止传递派发。
如上就是所有ViewGroup关于触摸屏事件的传递机制源码分析。具体总结如下： 1,Android事件派发是先传递到最顶级的ViewGroup，再由ViewGroup递归传递到View的。 2,在ViewGroup中可以通过onInterceptTouchEvent方法对事件传递进行拦截，3,onInterceptTouchEvent方法
1）返回true 代表不允许事件继续向子View传递，则交给这个ViewGroup的onTouchEvent处理
2）返回false 代表不对事件进行拦截，默认返回false，则交给子View的dispatchTouchEvent方法处理 4,事件传递到子view 的 dispatchTouchEvent方法中，通过方法传递到当前View的onTouchEvent方法中： （1）如果返回true，那么这个事件就会止于该view。 （2）如果返回 false ，那么这个事件会从这个子view 往上传递，而且都是传递到父View的onTouchEvent 来接收。
（3）如果传递到ViewGroup的 onTouchEvent 也返回 false 的话，则继续传递到Activity的onTouchEvent中，如果还是false,则这个事件就会“消失“；事件向上传递到中间的任何onTouchEvent方法中，如果返回true，则事件被消费掉，不会再传递。
View中触摸消息机制：
在Android中你只要触摸控件首先都会触发控件的dispatchTouchEvent方法（其实这个方法一般都没在具体的控件类中，而在他的父类View中），所以我们先来看下View的dispatchTouchEvent方法
View中的触摸消息机制： /** * Pass the touch screen motion event down to the target view, or this * view if it is the target. * * @param event The motion event to be dispatched. * @return True if the event was handled by the view, false otherwise. */ public boolean dispatchTouchEvent(MotionEvent event) { // If the event should be handled by accessibility focus first. if (event.isTargetAccessibilityFocus()) { // We don't have focus or no virtual descendant has it, do not handle the event. if (!isAccessibilityFocusedViewOrHost()) { return false; } // We have focus and got the event, then use normal event dispatch. event.setTargetAccessibilityFocus(false); } boolean result = false; if (mInputEventConsistencyVerifier != null) { mInputEventConsistencyVerifier.onTouchEvent(event, 0); } final int actionMasked = event.getActionMasked(); if (actionMasked == MotionEvent.ACTION_DOWN) { // Defensive cleanup for new gesture stopNestedScroll(); } if (onFilterTouchEventForSecurity(event)) { // 判断当前View是否没被遮住 //noinspection SimplifiableIfStatement ListenerInfo局部变量，ListenerInfo是View的静态内部类，用来定义一堆关于View的XXXListener等方法 ListenerInfo li = mListenerInfo; /**一,首先判断是不是设置onTouch监听器，onTouch的返回值 * 首先li对象自然不会为null, li.mOnTouchListener是不是null取决于控件（View）是否设置setOnTouchListener监听 * 接着通过位与运算确定控件（View）是不是ENABLED 的，默认控件都是ENABLED 的 * 接着判断onTouch的返回值是不是true */ if (li != null && li.mOnTouchListener != null && (mViewFlags & ENABLED_MASK) == ENABLED && li.mOnTouchListener.onTouch(this, event)) { result = true; //如果设置了onTouchListener，并且onTouch返回时true，result就是true，下一句if就不执行了，onTouchEvent和onClick就不执行了 } //上面的执行了result等于true，这句就不执行了。如果result是false，就执行onTouchEvent，onTouchEvent中有执行onClick的步骤 if (!result && onTouchEvent(event)) { result = true; } } if (!result && mInputEventConsistencyVerifier != null) { mInputEventConsistencyVerifier.onUnhandledEvent(event, 0); } // Clean up after nested scrolls if this is the end of a gesture; // also cancel it if we tried an ACTION_DOWN but we didn't want the rest // of the gesture. if (actionMasked == MotionEvent.ACTION_UP || actionMasked == MotionEvent.ACTION_CANCEL || (actionMasked == MotionEvent.ACTION_DOWN && !result)) { stopNestedScroll(); } return result; } 如果 if (li != null && li.mOnTouchListener != null && (mViewFlags & ENABLED_MASK) == ENABLED && li.mOnTouchListener.onTouch(this, event))语句有一个为false则 if (!result && onTouchEvent(event))就会执行，如果onTouchEvent(event)返回false则dispatchTouchEvent返回false，否则返回true。 控件触摸就会调运dispatchTouchEvent方法， 而在dispatchTouchEvent中先执行的是onTouch方法，所以验证了实例结论总结中的onTouch优先于onClick执行道理。如果控件是ENABLE且在onTouch方法里返回了true则dispatchTouchEvent方法也返回true，不会再继续往下执行；
反之，onTouch返回false则会继续向下执行onTouchEvent方法，且dispatchTouchEvent的返回值与onTouchEvent返回值相同。 所以依据这个结论和上面实例打印结果你指定已经大胆猜测认为onClick一定与onTouchEvent有关系？ 总结结论 在View的触摸屏传递机制中通过分析dispatchTouchEvent方法源码我们会得出如下基本结论： 1，触摸控件（View）首先执行dispatchTouchEvent方法。 2，在dispatchTouchEvent方法中先执行onTouch方法，后执行onClick方法（onClick方法在onTouchEvent中执行，下面会分析）。 3，如果控件（View）的onTouch返回false或者mOnTouchListener为null（控件没有设置setOnTouchListener方法）或者控件不是enable的情况下会调运onTouchEvent，dispatchTouchEvent返回值与onTouchEvent返回一样。 4，如果控件不是enable的设置了onTouch方法也不会执行，只能通过重写控件的onTouchEvent方法处理（上面已经处理分析了），dispatchTouchEvent返回值与onTouchEvent返回一样。 5，如果控件（View）是enable且onTouch返回true情况下，dispatchTouchEvent直接返回true，不会调用onTouchEvent方法。 View的dispatchTouchEvent方法中调运的onTouchEvent方法
/** * Implement this method to handle touch screen motion events. * <p> * If this method is used to detect click actions, it is recommended that * the actions be performed by implementing and calling * {@link #performClick()}. This will ensure consistent system behavior, * including: * <ul> * <li>obeying click sound preferences * <li>dispatching OnClickListener calls * <li>handling {@link AccessibilityNodeInfo#ACTION_CLICK ACTION_CLICK} when * accessibility features are enabled * </ul> * * @param event The motion event. * @return True if the event was handled, false otherwise. */ public boolean onTouchEvent(MotionEvent event) { final float x = event.getX(); final float y = event.getY(); final int viewFlags = mViewFlags; if ((viewFlags & ENABLED_MASK) == DISABLED) { // 组件设置的disabled，组件不可用，那就直接返回了 if (event.getAction() == MotionEvent.ACTION_UP && (mPrivateFlags & PFLAG_PRESSED) != 0) { setPressed(false); } // A disabled view that is clickable still consumes the touch // events, it just doesn't respond to them. return (((viewFlags & CLICKABLE) == CLICKABLE || (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)); } if (mTouchDelegate != null) { if (mTouchDelegate.onTouchEvent(event)) { return true; } } if (((viewFlags & CLICKABLE) == CLICKABLE || (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)) { //如果组件是enabled且可点击，或者可长点击 switch (event.getAction()) { case MotionEvent.ACTION_UP: boolean prepressed = (mPrivateFlags & PFLAG_PREPRESSED) != 0; if ((mPrivateFlags & PFLAG_PRESSED) != 0 || prepressed) { // take focus if we don't have it already and we should in // touch mode. // 首先判断了是否按下过，同时是不是可以得到焦点，然后尝试获取焦点，然后判断如果不是longPressed则通过post在UI Thread中执行一个PerformClick的Runnable，也就是performClick方法。 boolean focusTaken = false; if (isFocusable() && isFocusableInTouchMode() && !isFocused()) { focusTaken = requestFocus(); } if (prepressed) { // The button is being released before we actually // showed it as pressed. Make it show the pressed // state now (before scheduling the click) to ensure // the user sees it. setPressed(true, x, y); } if (!mHasPerformedLongPress) { // This is a tap, so remove the longpress check removeLongPressCallback(); // Only perform take click actions if we were in the pressed state if (!focusTaken) { // Use a Runnable and post this rather than calling // performClick directly. This lets other visual state // of the view update before click actions start. // 使用post一个Runnable的PerformClick的任务类而不是直接调用performClick的方法。 if (mPerformClick == null) { mPerformClick = new PerformClick(); } if (!post(mPerformClick)) { performClick();// 终于找到了，onClick方法在performClick的函数中 } } } if (mUnsetPressedState == null) { mUnsetPressedState = new UnsetPressedState(); } if (prepressed) { postDelayed(mUnsetPressedState, ViewConfiguration.getPressedStateDuration()); } else if (!post(mUnsetPressedState)) { // If the post failed, unpress right now mUnsetPressedState.run(); } removeTapCallback(); } break; // ACTION_DOWN与ACTION_MOVE都进行了一些必要的设置与置位 case MotionEvent.ACTION_DOWN: mHasPerformedLongPress = false; if (performButtonActionOnTouchDown(event)) { break; } // Walk up the hierarchy to determine if we're inside a scrolling container. boolean isInScrollingContainer = isInScrollingContainer(); // For views inside a scrolling container, delay the pressed feedback for // a short period in case this is a scroll. if (isInScrollingContainer) { mPrivateFlags |= PFLAG_PREPRESSED; if (mPendingCheckForTap == null) { mPendingCheckForTap = new CheckForTap(); } mPendingCheckForTap.x = event.getX(); mPendingCheckForTap.y = event.getY(); postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); } else { // Not inside a scrolling container, so show the feedback right away setPressed(true, x, y); checkForLongClick(0); } break; case MotionEvent.ACTION_CANCEL: setPressed(false); removeTapCallback(); removeLongPressCallback(); break; case MotionEvent.ACTION_MOVE: drawableHotspotChanged(x, y); // Be lenient about moving outside of buttons if (!pointInView(x, y, mTouchSlop)) { // Outside button removeTapCallback(); if ((mPrivateFlags & PFLAG_PRESSED) != 0) { // Remove any future long press/tap checks removeLongPressCallback(); setPressed(false); } } break; } return true; } return false; } <span style="font-size:24px;">/** * Call this view's OnClickListener, if it is defined. Performs all normal * actions associated with clicking: reporting accessibility event, playing * a sound, etc. *调用这个view的OnClickListener方法。 * @return True there was an assigned OnClickListener that was called, false * otherwise is returned. */ public boolean performClick() { final boolean result; final ListenerInfo li = mListenerInfo; if (li != null && li.mOnClickListener != null) { // 和dispatchTouchEvent中的判断一样，li自然不是null,如果设置了OnclickListener那么 li.mOnClickListener也不为空 playSoundEffect(SoundEffectConstants.CLICK); li.mOnClickListener.onClick(this); // 这个是重点！！！！！，执行这个View的Onclick方法，返回true result = true; } else { result = false; } sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED); return result; } </span> 猜的没错onClick就在onTouchEvent中执行的，而且是在onTouchEvent的ACTION_UP事件中执行的
总结结论 1，onTouchEvent方法中会在ACTION_UP分支中触发onClick的监听。 2，当dispatchTouchEvent在进行事件分发的时候，只有前一个action返回true，才会触发下一个action。
参考：http://blog.csdn.net/yanbober/article/details/45887547
