Event Distribution Process

As you can see from the figure above, the focus of event distribution is dispatchTouchEvent

Analysis of ViewGroup

DispatchTouchEvent analysis for ViewGroup

Step1: Clears the state if it is a new event

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();
}
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The Down event is the start of a time series that clears the previous state. Reset TouchTargets clear View held by TouchTarget Step2: Whether to intercept

if (actionMasked == MotionEvent.ACTION_DOWN || mFirstTouchTarget ! = null) { final boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) ! = 0; if (! disallowIntercept) { intercepted = onInterceptTouchEvent(ev); ev.setAction(action); // restore action in case it was changed } else { intercepted = false; } } else { // There are no touch targets and this action is not an initial down // so this view group continues to intercepted = true; }Copy the code

If it is a Down event or mFirstTouchTarget is not null, the event is consumed. OnInterceptTouchEvent (EV) returns false by default

public boolean onInterceptTouchEvent(MotionEvent ev) {
    if (ev.isFromSource(InputDevice.SOURCE_MOUSE)
            && ev.getAction() == MotionEvent.ACTION_DOWN
            && ev.isButtonPressed(MotionEvent.BUTTON_PRIMARY)
            && isOnScrollbarThumb(ev.getX(), ev.getY())) {
        return true;
    }
    return false;
}
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Step3: execute the process normally

if (! canceled && ! Intercepted) {/ / for children with focus View childWithAccessibilityFocus = ev. IsTargetAccessibilityFocus ()? findChildWithAccessibilityFocus() : null; / / if the down event enter below the 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; / / remove pointer id removePointersFromTouchTargets (idBitsToAssign); final int childrenCount = mChildrenCount; if (newTouchTarget == null && childrenCount ! = 0) { final float x = ev.getX(actionIndex); final float y = ev.getY(actionIndex); / / find children can receive events, from the beginning to the end to find final ArrayList < View > preorderedList = buildTouchDispatchChildList (); final boolean customOrder = preorderedList == null && isChildrenDrawingOrderEnabled(); final View[] children = mChildren; for (int i = childrenCount - 1; i >= 0; i--) { final int childIndex = getAndVerifyPreorderedIndex( childrenCount, i, customOrder); final View child = getAndVerifyPreorderedView( preorderedList, children, childIndex); / / if the child has a focus to traverse the if (childWithAccessibilityFocus! = null) { if (childWithAccessibilityFocus ! = child) { continue; } childWithAccessibilityFocus = null; i = childrenCount - 1; } / / filter cannot receive events and to be outside the scope of finger click on children / / canViewReceivePointerEvent visible or in the execution animation representative to receive events / / isTransformedTouchPointInView x, y point is within the scope of the children  if (! canViewReceivePointerEvents(child) || ! isTransformedTouchPointInView(x, y, child, null)) { ev.setTargetAccessibilityFocus(false); continue; } newTouchTarget = getTouchTarget(child); if (newTouchTarget ! = null) {/ / to touch the target set for the new pointer exit loop newTouchTarget. PointerIdBits | = idBitsToAssign; break; } // Reset the child's up flag resetCancelNextUpFlag(child); / / distribution convert touch events if (dispatchTransformedTouchEvent (ev, false, child, idBitsToAssign)) {/ / 1 record down time, MLastTouchDownTime = ev.getdowntime (); 1 if (preorderedList ! = null) {2 // 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(); 3 mLastTouchDownY = ev.getY(); NewTouchTarget = addTouchTarget(Child, idBitsToAssign); // Add the child to the start of the touch target. 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; } } // 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; // Distribute events to touch targets 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; }Copy the code

Distribution process

    // ViewGroup
    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        boolean handled = false;
        if (onFilterTouchEventForSecurity(ev)) {
            final int action = ev.getAction();
            final int actionMasked = action & MotionEvent.ACTION_MASK;

            //1.
            if (actionMasked == MotionEvent.ACTION_DOWN) {
                // 在down事件开始 重置状态 重置记录的触摸目标
                cancelAndClearTouchTargets(ev);
                resetTouchState();
            }

            // 2. 检查拦截
            final boolean intercepted;
            if (actionMasked == MotionEvent.ACTION_DOWN
                    || mFirstTouchTarget != null) {
                final boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0;
                if (!disallowIntercept) {
                    intercepted = onInterceptTouchEvent(ev);
                    ev.setAction(action); // restore action in case it was changed
                } else {
                    intercepted = false;
                }
            } else {
                // 没有触摸目标
                intercepted = true;
            }


           // 3.分发事件
            final boolean canceled = resetCancelNextUpFlag(this)
                    || actionMasked == MotionEvent.ACTION_CANCEL;

            // 多点触控
            final boolean split = (mGroupFlags & FLAG_SPLIT_MOTION_EVENTS) != 0;
            TouchTarget newTouchTarget = null;
            boolean alreadyDispatchedToNewTouchTarget = false;
            if (!canceled && !intercepted) {// 非取消非拦截
                View childWithAccessibilityFocus = ev.isTargetAccessibilityFocus()
                        ? findChildWithAccessibilityFocus() : null;
                // down事件进入
                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;
                    removePointersFromTouchTargets(idBitsToAssign);

                    final int childrenCount = mChildrenCount;
                    if (newTouchTarget == null && childrenCount != 0) {
                        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 = buildTouchDispatchChildList();
                        final boolean customOrder = preorderedList == null
                                && isChildrenDrawingOrderEnabled();
                        final View[] children = mChildren;
                        for (int i = childrenCount - 1; i >= 0; i--) {
                            // 查找触控落点的view，把事件分发给他
                            if (!canViewReceivePointerEvents(child)
                                    || !isTransformedTouchPointInView(x, y, child, null)) {
                                ev.setTargetAccessibilityFocus(false);
                                continue;
                            }

                            newTouchTarget = getTouchTarget(child);
                            if (newTouchTarget != null) {
                                // 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);
                            if (dispatchTransformedTouchEvent(ev, false, child, idBitsToAssign)) {
                                newTouchTarget = addTouchTarget(child, idBitsToAssign);
                                alreadyDispatchedToNewTouchTarget = true;
                                break;
                            }

                            ev.setTargetAccessibilityFocus(false);
                        }
                   
                    }
                    // 把找到的触摸目标加到链表
                    if (newTouchTarget == null && mFirstTouchTarget != null) {
                        while (newTouchTarget.next != null) {
                            newTouchTarget = newTouchTarget.next;
                        }
                        newTouchTarget.pointerIdBits |= idBitsToAssign;
                    }
                }
            }

            // 4. 把事件分发给触摸目标 Dispatch to touch targets.
            if (mFirstTouchTarget == null) {
                // 这一步会让ViewGroup退化成View执行dispatchTouchEvent
                handled = dispatchTransformedTouchEvent(ev, canceled, null,
                        TouchTarget.ALL_POINTER_IDS);
            } else {
                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;
                }
            }

        }
        return handled;
    }

    // 5. 分发给子View
    private boolean dispatchTransformedTouchEvent(MotionEvent event, boolean cancel,
            View child, int desiredPointerIdBits) {
        final boolean handled;
        final int oldAction = event.getAction();
        // a. 处理cancel事件
        if (cancel || oldAction == MotionEvent.ACTION_CANCEL) {
            event.setAction(MotionEvent.ACTION_CANCEL);
            if (child == null) {
                handled = super.dispatchTouchEvent(event);
            } else {
                handled = child.dispatchTouchEvent(event);
            }
            event.setAction(oldAction);
            return handled;
        }

        if (child == null) {
            //b. 执行View的dispatchTouchEvent
            handled = super.dispatchTouchEvent(transformedEvent);
        } else {
            final float offsetX = mScrollX - child.mLeft;
            final float offsetY = mScrollY - child.mTop;
            transformedEvent.offsetLocation(offsetX, offsetY);
            if (! child.hasIdentityMatrix()) {
                transformedEvent.transform(child.getInverseMatrix());
            }
            // c. 分发给子View
            handled = child.dispatchTouchEvent(transformedEvent);
        }

        // Done.
        transformedEvent.recycle();// 回收池回收MotionEvent对象
        return handled;
    }

    // View
    public boolean dispatchTouchEvent(MotionEvent event) {
        if (onFilterTouchEventForSecurity(event)) {
            if ((mViewFlags & ENABLED_MASK) == ENABLED && handleScrollBarDragging(event)) {
                result = true;
            }
            // OnTouchListener.onTouch
            if (li != null && li.mOnTouchListener != null
                    && (mViewFlags & ENABLED_MASK) == ENABLED
                    && li.mOnTouchListener.onTouch(this, event)) {
                result = true;
            }
            // onTouchEvent
            if (!result && onTouchEvent(event)) {
                result = true;
            }
        }
        return result;
    }

    public boolean onTouchEvent(MotionEvent event) {
        final float x = event.getX();
        final float y = event.getY();
        final int viewFlags = mViewFlags;
        final int action = event.getAction();

        final boolean clickable = ((viewFlags & CLICKABLE) == CLICKABLE
                || (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)
                || (viewFlags & CONTEXT_CLICKABLE) == CONTEXT_CLICKABLE;
        // a.如果enable为false 直接返回
        if ((viewFlags & ENABLED_MASK) == DISABLED) {
            if (action == MotionEvent.ACTION_UP && (mPrivateFlags & PFLAG_PRESSED) != 0) {
                setPressed(false);
            }
            mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
            return clickable;
        }

        if (clickable || (viewFlags & TOOLTIP) == TOOLTIP) {
            switch (action) {
                case MotionEvent.ACTION_UP: // b. up事件执行performClick 内部会回调mOnClickListener.onClick

                    if (mPerformClick == null) {
                        mPerformClick = new PerformClick();
                    }
                    if (!post(mPerformClick)) {
                        performClickInternal();
                    }
                    break;

                case MotionEvent.ACTION_DOWN:
                    break;

                case MotionEvent.ACTION_CANCEL:
                    break;

                case MotionEvent.ACTION_MOVE:
                    break;
            }

            return true;
        }

        return false;
    }




// 场景1：没有子View消费任何事件 ViewGroup退化成View执行dispatchTouchEvent最终执行onTouchEvent 所以就出现 子View不消费 一级一级抛给上层消费
2021-09-07 10:17:01.889 18900-18900/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Down
2021-09-07 10:17:01.892 18900-18900/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Down
2021-09-07 10:17:01.892 18900-18900/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Down
2021-09-07 10:17:01.892 18900-18900/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Down
2021-09-07 10:17:01.892 18900-18900/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Down
2021-09-07 10:17:01.893 18900-18900/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Down
2021-09-07 10:17:01.893 18900-18900/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Down
2021-09-07 10:17:01.893 18900-18900/com.example.testandroid I/Liuzj: MyFrameLayout----onTouchEvent:  Down 退化为View
2021-09-07 10:17:01.893 18900-18900/com.example.testandroid I/Liuzj: MyLinearLayout----onTouchEvent:  Down 退化为View
2021-09-07 10:17:01.894 18900-18900/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Down 退化为View
2021-09-07 10:17:01.978 18900-18900/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Up 没有子View消费所以DecorView变为拦截后续事件所以只有Activity处理后续事件
2021-09-07 10:17:01.979 18900-18900/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Up
2021-09-07 10:45:45.140 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.141 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.360 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.361 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.377 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.377 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.393 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.393 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.410 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.410 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.427 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.427 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.525 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.525 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.542 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:45:45.542 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:45:45.664 21064-21064/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Up
2021-09-07 10:45:45.664 21064-21064/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Up

// 场景2 子View消费Down事件 由于有子View消费事件所以TouchTarget不会空 所以后续事件都可以分发
2021-09-07 10:47:55.919 21271-21271/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Down
2021-09-07 10:47:55.922 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Down
2021-09-07 10:47:55.923 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Down
2021-09-07 10:47:55.923 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Down
2021-09-07 10:47:55.923 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Down
2021-09-07 10:47:55.924 21271-21271/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Down
2021-09-07 10:47:55.924 21271-21271/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Down
2021-09-07 10:47:56.269 21271-21271/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:47:56.271 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.271 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.271 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.272 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.272 21271-21271/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Move
2021-09-07 10:47:56.272 21271-21271/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Move
2021-09-07 10:47:56.273 21271-21271/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:47:56.890 21271-21271/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:47:56.890 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Move
2021-09-07 10:47:56.891 21271-21271/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:47:56.911 21271-21271/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Move
2021-09-07 10:47:56.911 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.911 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.911 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Move
2021-09-07 10:47:56.912 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Move
2021-09-07 10:47:56.912 21271-21271/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Move
2021-09-07 10:47:56.912 21271-21271/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Move
2021-09-07 10:47:56.912 21271-21271/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Move
2021-09-07 10:47:56.928 21271-21271/com.example.testandroid I/Liuzj: MainActivity----dispatchTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----dispatchTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyLinearLayout----onInterceptTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----dispatchTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyFrameLayout----onInterceptTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyTextView----dispatchTouchEvent:  Up
2021-09-07 10:47:56.929 21271-21271/com.example.testandroid I/Liuzj: MyTextView----onTouchEvent:  Up
2021-09-07 10:47:56.930 21271-21271/com.example.testandroid I/Liuzj: MainActivity----onTouchEvent:  Up

    
Copy the code

About TouchTarget

www.jianshu.com/p/5951ebdd2…