Android 高级UI4 事件传递机制

作者: 香沙小熊 | 来源:发表于2018-06-06 13:25 被阅读95次

1.View的事件分发

流程

dispatchTouchEvent():
onTouchListener--->onTouch方法
onTouchEvent
onClickListener--->onClick方法

ListenerInfo

    static class ListenerInfo {
        /**
         * Listener used to dispatch focus change events.
         * This field should be made private, so it is hidden from the SDK.
         * {@hide}
         */
        protected OnFocusChangeListener mOnFocusChangeListener;

        /**
         * Listeners for layout change events.
         */
        private ArrayList<OnLayoutChangeListener> mOnLayoutChangeListeners;

        protected OnScrollChangeListener mOnScrollChangeListener;

        /**
         * Listeners for attach events.
         */
        private CopyOnWriteArrayList<OnAttachStateChangeListener> mOnAttachStateChangeListeners;

        /**
         * Listener used to dispatch click events.
         * This field should be made private, so it is hidden from the SDK.
         * {@hide}
         */
        public OnClickListener mOnClickListener;

        /**
         * Listener used to dispatch long click events.
         * This field should be made private, so it is hidden from the SDK.
         * {@hide}
         */
        protected OnLongClickListener mOnLongClickListener;

        /**
         * Listener used to dispatch context click events. This field should be made private, so it
         * is hidden from the SDK.
         * {@hide}
         */
        protected OnContextClickListener mOnContextClickListener;

        /**
         * Listener used to build the context menu.
         * This field should be made private, so it is hidden from the SDK.
         * {@hide}
         */
        protected OnCreateContextMenuListener mOnCreateContextMenuListener;

        private OnKeyListener mOnKeyListener;

        private OnTouchListener mOnTouchListener;

        private OnHoverListener mOnHoverListener;

        private OnGenericMotionListener mOnGenericMotionListener;

        private OnDragListener mOnDragListener;

        private OnSystemUiVisibilityChangeListener mOnSystemUiVisibilityChangeListener;

        OnApplyWindowInsetsListener mOnApplyWindowInsetsListener;

        OnCapturedPointerListener mOnCapturedPointerListener;
    }

dispatchTouchEvent

    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)) {
            if ((mViewFlags & ENABLED_MASK) == ENABLED && handleScrollBarDragging(event)) {
                result = true;
            }
            //noinspection SimplifiableIfStatement
            ListenerInfo li = mListenerInfo;
            if (li != null && li.mOnTouchListener != null
                    && (mViewFlags & ENABLED_MASK) == ENABLED
                    && li.mOnTouchListener.onTouch(this, event)) {
                result = true;
            }

            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;
    }

onTouchEvent

/**
     * 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;
        final int action = event.getAction();

        final boolean clickable = ((viewFlags & CLICKABLE) == CLICKABLE
                || (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)
                || (viewFlags & CONTEXT_CLICKABLE) == CONTEXT_CLICKABLE;

        if ((viewFlags & ENABLED_MASK) == DISABLED) {
            if (action == MotionEvent.ACTION_UP && (mPrivateFlags & PFLAG_PRESSED) != 0) {
                setPressed(false);
            }
            mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
            // A disabled view that is clickable still consumes the touch
            // events, it just doesn't respond to them.
            return clickable;
        }
        if (mTouchDelegate != null) {
            if (mTouchDelegate.onTouchEvent(event)) {
                return true;
            }
        }

        if (clickable || (viewFlags & TOOLTIP) == TOOLTIP) {
            switch (action) {
                case MotionEvent.ACTION_UP:
                    mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
                    if ((viewFlags & TOOLTIP) == TOOLTIP) {
                        handleTooltipUp();
                    }
                    if (!clickable) {
                        removeTapCallback();
                        removeLongPressCallback();
                        mInContextButtonPress = false;
                        mHasPerformedLongPress = false;
                        mIgnoreNextUpEvent = false;
                        break;
                    }
                    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.
                        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 && !mIgnoreNextUpEvent) {
                            // 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.
                                if (mPerformClick == null) {
                                    mPerformClick = new PerformClick();
                                }
                                if (!post(mPerformClick)) {
                                    performClick();
                                }
                            }
                        }

                        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();
                    }
                    mIgnoreNextUpEvent = false;
                    break;

                case MotionEvent.ACTION_DOWN:
                    if (event.getSource() == InputDevice.SOURCE_TOUCHSCREEN) {
                        mPrivateFlags3 |= PFLAG3_FINGER_DOWN;
                    }
                    mHasPerformedLongPress = false;

                    if (!clickable) {
                        checkForLongClick(0, x, y);
                        break;
                    }

                    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, x, y);
                    }
                    break;

                case MotionEvent.ACTION_CANCEL:
                    if (clickable) {
                        setPressed(false);
                    }
                    removeTapCallback();
                    removeLongPressCallback();
                    mInContextButtonPress = false;
                    mHasPerformedLongPress = false;
                    mIgnoreNextUpEvent = false;
                    mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
                    break;

                case MotionEvent.ACTION_MOVE:
                    if (clickable) {
                        drawableHotspotChanged(x, y);
                    }

                    // Be lenient about moving outside of buttons
                    if (!pointInView(x, y, mTouchSlop)) {
                        // Outside button
                        // Remove any future long press/tap checks
                        removeTapCallback();
                        removeLongPressCallback();
                        if ((mPrivateFlags & PFLAG_PRESSED) != 0) {
                            setPressed(false);
                        }
                        mPrivateFlags3 &= ~PFLAG3_FINGER_DOWN;
                    }
                    break;
            }

            return true;
        }

        return false;
    }

performClick

   /**
     * Call this view's OnClickListener, if it is defined.  Performs all normal
     * actions associated with clicking: reporting accessibility event, playing
     * a sound, etc.
     *
     * @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) {
            playSoundEffect(SoundEffectConstants.CLICK);
            li.mOnClickListener.onClick(this);
            result = true;
        } else {
            result = false;
        }

        sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED);

        notifyEnterOrExitForAutoFillIfNeeded(true);

        return result;
    }

public class MyButton extends android.support.v7.widget.AppCompatButton {
    public MyButton(Context context) {
        super(context);
    }

    public MyButton(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent event) {
        Log.i("kpioneer", "dispatchTouchEvent:action--" + event.getAction());
        return super.dispatchTouchEvent(event);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.i("kpioneer", "onTouchEvent:action--" + event.getAction());
        return super.onTouchEvent(event);
    }
}

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;

/**
 * Created by Xionghu on 2018/6/5.
 * Desc:
 */

public class MainActivity extends Activity implements View.OnTouchListener, View.OnClickListener {

    private Button button1;
    private RelativeLayout layout;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        button1 = (Button)findViewById(R.id.button1);
        layout = (RelativeLayout)findViewById(R.id.layout);

        layout.setOnTouchListener(this);
        button1.setOnTouchListener(this);

        layout.setOnClickListener(this);
        button1.setOnClickListener(this);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        Log.i("kpioneer", "OnTouchListener:acton--"+event.getAction()+"----view:"+v);
        return false;
    }

    @Override
    public void onClick(View v) {
        Log.i("kpioneer", "OnClickListener----view:"+v);
    }

}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/layout"
    >

    <com.haocai.eventdemo.MyButton
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="14dp"
        android:text="Button" />

</RelativeLayout>

结论：

控件的Listener事件触发的顺序是onTouch，再onClick
控件的onTouch返回true,将会使onClick的事件没有了---阻止了事件的传递。返回false，才会传递onClick事件。
如果onTouchListener的onTouch方法返回了true，那么view里面的onTouchEvent就不会被调用了。顺序dispatchTouchEvent-->onTouchListener---return false-->onTouchEvent
如果view为disenable,则：onTouchListener里面不会执行，但是会执行onTouchEvent(event)方法
onTouchEvent方法中的ACTION_UP分支中触发onclick事件监听
onTouchListener-->onTouch方法返回true，消耗次事件。down,但是up事件是无法到达onClickListener.
onTouchListener-->onTouch方法返回false，不会消耗此事件

2.ViewGroup+View的事件分发

ViewGroup继承View

dispatchTouchEvent()
onInterceptTouchEvent() (拦截触摸，ViewGroup独有)
onTouchEvent()

dispatchTouchEvent

  @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;

            // 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.
            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 {
                // There are no touch targets and this action is not an initial down
                // so this view group continues to intercept touches.
                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.
            final boolean canceled = resetCancelNextUpFlag(this)
                    || actionMasked == MotionEvent.ACTION_CANCEL;

            // Update list of touch targets for pointer down, if needed.
            final boolean split = (mGroupFlags & FLAG_SPLIT_MOTION_EVENTS) != 0;
            TouchTarget newTouchTarget = null;
            boolean alreadyDispatchedToNewTouchTarget = false;
            if (!canceled && !intercepted) {

                // 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) {
                        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--) {
                            final int childIndex = getAndVerifyPreorderedIndex(
                                    childrenCount, i, customOrder);
                            final View child = getAndVerifyPreorderedView(
                                    preorderedList, children, 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);
                            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)) {
                                // 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;
                    }
                }
            }

            // 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;
    }

onInterceptTouchEvent

  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;
    }

示例

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

/**
 * Created by Xionghu on 2018/6/6.
 * Desc:
 */

public class MyRelativeLayout extends RelativeLayout {
    public MyRelativeLayout(Context context) {
        super(context);
    }

    public MyRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        Log.i("kpioneer", "dispatchTouchEvent:action--"+ev.getAction()+"---view:MyRelativeLayout");
        return super.dispatchTouchEvent(ev);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        Log.i("kpioneer", "onInterceptTouchEvent:action--"+ev.getAction()+"---view:MyRelativeLayout");
        return super.onInterceptTouchEvent(ev);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.i("kpioneer", "onTouchEvent:action--"+event.getAction()+"---view:MyRelativeLayout");
        return super.onTouchEvent(event);
    }
}

点击Button

06-06 11:05:18.340 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--0---view:MyRelativeLayout
06-06 11:05:18.340 27438-27438/com.haocai.eventdemo I/kpioneer: onInterceptTouchEvent:action--0---view:MyRelativeLayout
06-06 11:05:18.340 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--0
06-06 11:05:18.340 27438-27438/com.haocai.eventdemo I/kpioneer: OnTouchListener:acton--0----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ........ 0,42-264,186 #7f070022 app:id/button1}
06-06 11:05:18.340 27438-27438/com.haocai.eventdemo I/kpioneer: onTouchEvent:action--0
06-06 11:05:18.370 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.370 27438-27438/com.haocai.eventdemo I/kpioneer: onInterceptTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.370 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2
06-06 11:05:18.370 27438-27438/com.haocai.eventdemo I/kpioneer: OnTouchListener:acton--2----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ...P.... 0,42-264,186 #7f070022 app:id/button1}
06-06 11:05:18.380 27438-27438/com.haocai.eventdemo I/kpioneer: onTouchEvent:action--2
06-06 11:05:18.390 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.390 27438-27438/com.haocai.eventdemo I/kpioneer: onInterceptTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.390 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2
06-06 11:05:18.390 27438-27438/com.haocai.eventdemo I/kpioneer: OnTouchListener:acton--2----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ...P.... 0,42-264,186 #7f070022 app:id/button1}
06-06 11:05:18.390 27438-27438/com.haocai.eventdemo I/kpioneer: onTouchEvent:action--2
06-06 11:05:18.400 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.400 27438-27438/com.haocai.eventdemo I/kpioneer: onInterceptTouchEvent:action--2---view:MyRelativeLayout
06-06 11:05:18.400 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--2
06-06 11:05:18.400 27438-27438/com.haocai.eventdemo I/kpioneer: OnTouchListener:acton--2----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ...P.... 0,42-264,186 #7f070022 app:id/button1}
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: onTouchEvent:action--2
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--1---view:MyRelativeLayout
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: onInterceptTouchEvent:action--1---view:MyRelativeLayout
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: dispatchTouchEvent:action--1
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: OnTouchListener:acton--1----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ...P.... 0,42-264,186 #7f070022 app:id/button1}
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: onTouchEvent:action--1
06-06 11:05:18.410 27438-27438/com.haocai.eventdemo I/kpioneer: OnClickListener----view:com.haocai.eventdemo.MyButton{8e32527 VFED..C.. ...P.... 0,42-264,186 #7f070022 app:id/button1}

该例子中Button事件点击：

先接触到事件的是父容器
ViewGroup顺序：dispatchTouchEvent--->onInterceptTouchevent-->dispatchTouchEvent（Button）-->OnTouchListener(Button) --->return false---> onTouchEvent（Button）（消耗事件） ----- onTouchevent(该示例父布局并没调用)

Android 高级UI4 事件传递机制

1.View的事件分发

流程

ListenerInfo

dispatchTouchEvent

onTouchEvent

performClick

结论：

2.ViewGroup+View的事件分发

dispatchTouchEvent

onInterceptTouchEvent

示例

该例子中Button事件点击：

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