Java View.dispatchTouchEvent方法代码示例

import android.view.View; //导入方法依赖的package包/类
/**
 * Duplicate touch events to child views.
 * We want to dispatch a down motion event and the move events to
 * child views, but calling dispatchTouchEvent() causes StackOverflowError.
 * Therefore we do it manually.
 *
 * @param ev            motion event to be passed to children
 * @param pendingEvents pending events like ACTION_DOWN. This will be passed to the children before ev
 */
private void duplicateTouchEventForChildren(MotionEvent ev, MotionEvent... pendingEvents) {
    if (ev == null) {
        return;
    }
    for (int i = getChildCount() - 1; 0 <= i; i--) {
        View childView = getChildAt(i);
        if (childView != null) {
            Rect childRect = new Rect();
            childView.getHitRect(childRect);
            MotionEvent event = MotionEvent.obtainNoHistory(ev);
            if (!childRect.contains((int) event.getX(), (int) event.getY())) {
                continue;
            }
            float offsetX = -childView.getLeft();
            float offsetY = -childView.getTop();
            boolean consumed = false;
            if (pendingEvents != null) {
                for (MotionEvent pe : pendingEvents) {
                    if (pe != null) {
                        MotionEvent peAdjusted = MotionEvent.obtainNoHistory(pe);
                        peAdjusted.offsetLocation(offsetX, offsetY);
                        consumed |= childView.dispatchTouchEvent(peAdjusted);
                    }
                }
            }
            event.offsetLocation(offsetX, offsetY);
            consumed |= childView.dispatchTouchEvent(event);
            if (consumed) {
                break;
            }
        }
    }
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean onTouchEvent(MotionEvent event) {
    int width = getWidth() / getChildCount();
    int height = getHeight();
    int count = getChildCount();
    float eventX = event.getX();
    if (eventX < width) {
        getChildAt(0).dispatchTouchEvent(event);
    } else if (eventX > width && eventX < 2 * width) {
        float eventY = event.getY();
        if (eventY < height / 2) {
            for (int i = 0; i < count; i++) {
                View child = getChildAt(i);
                child.dispatchTouchEvent(event);
            }
        } else {
            getChildAt(1).dispatchTouchEvent(event);
        }
    } else if (eventX > 2 * width) {
        getChildAt(2).dispatchTouchEvent(event);
    }

    return true;
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
    final int actionMasked = motionEvent.getActionMasked();
    if (actionMasked == MotionEvent.ACTION_DOWN) {
        if (view instanceof ViewGroup) {
            mInitialTouchTarget = findNearestChild((ViewGroup) view,
                    (int) motionEvent.getX(), (int) motionEvent.getY());
        } else {
            mInitialTouchTarget = null;
        }
    }

    final View child = mInitialTouchTarget;
    if (child == null) {
        return false;
    }

    final float offsetX = view.getScrollX() - child.getLeft();
    final float offsetY = view.getScrollY() - child.getTop();
    motionEvent.offsetLocation(offsetX, offsetY);
    final boolean handled = child.dispatchTouchEvent(motionEvent);
    motionEvent.offsetLocation(-offsetX, -offsetY);

    if (actionMasked == MotionEvent.ACTION_UP
            || actionMasked == MotionEvent.ACTION_CANCEL) {
        mInitialTouchTarget = null;
    }

    return handled;
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
    for (int i = 0; i < getChildCount(); i++) {
        View child = getChildAt(i);
        try {
            child.dispatchTouchEvent(ev);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    return true;
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean onTouchEvent(CoordinatorLayout parent, View child, MotionEvent ev) {
    if (!mShouldIntercept) return false;
    ev.offsetLocation(-child.getX(), -child.getY());
    child.dispatchTouchEvent(ev);
    return true;
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean propagateEvent(MotionEvent e) {
    if (e == null) return false;

    View view = getActiveLayout().getViewForInteraction();
    if (view == null) return false;

    e.offsetLocation(-view.getLeft(), -view.getTop());
    return view.dispatchTouchEvent(e);
}
 

import android.view.View; //导入方法依赖的package包/类
@Override
public boolean onTouchEvent(MotionEvent event) {
    updateSourcePartial();

    // The logic below is mostly copied from the parent class, since we
    // can't update private mBounds variable.

    // http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;
    // f=core/java/android/view/TouchDelegate.java;hb=eclair#l98

    final Rect sourcePartial = mSourcePartial;
    final View target = mTarget;

    int x = (int)event.getX();
    int y = (int)event.getY();

    boolean sendToDelegate = false;
    boolean hit = true;
    boolean handled = false;

    switch (event.getAction()) {
    case MotionEvent.ACTION_DOWN:
        if (sourcePartial.contains(x, y)) {
            mDelegateTargeted = true;
            sendToDelegate = true;
        }
        break;
    case MotionEvent.ACTION_UP:
    case MotionEvent.ACTION_MOVE:
        sendToDelegate = mDelegateTargeted;
        if (sendToDelegate) {
            if (!sourcePartial.contains(x, y)) {
                hit = false;
            }
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        sendToDelegate = mDelegateTargeted;
        mDelegateTargeted = false;
        break;
    }

    if (sendToDelegate) {
        if (hit) {
            event.setLocation(target.getWidth() / 2, target.getHeight() / 2);
        } else {
            event.setLocation(-1, -1);
        }
        handled = target.dispatchTouchEvent(event);
    }
    return handled;
}
 

import android.view.View; //导入方法依赖的package包/类
/**
 * fake a ACTION_DOWN to adjust child's motion track
 *
 * @param v
 * @param e
 */
private void adjustDownMotion(View v, MotionEvent e) {
    MotionEvent fakeDownEvent = MotionEvent.obtain(e);
    fakeDownEvent.setAction(MotionEvent.ACTION_DOWN);
    v.dispatchTouchEvent(fakeDownEvent);
}