Android的GestureDetector与内SurfaceView SimpleOnGestureListener [英] Android GestureDetector with SimpleOnGestureListener within SurfaceView

问题描述

public class GameActivity extends Activity {
    private static final String TAG = "GameActivity";

   . . .

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.d(TAG, "+ onTouchEvent(event:" + event + ")");
        Log.d(TAG, "- onTouchEvent()");
        return super.onTouchEvent(event);
    }

    . . .
}


public class GameView extends SurfaceView implements SurfaceHolder.Callback {
    private static final String TAG = "GameView";

    . . .

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.d(TAG, "+ onTouchEvent(event:" + event + ")");
        gestureDetector.onTouchEvent(event);
        Log.d(TAG, "- onTouchEvent()");
        return super.onTouchEvent(event);
    }

    private SimpleOnGestureListener gestureListener = new SimpleOnGestureListener() {
        private static final String TAG = "GestureListener";

        @Override
        public boolean onSingleTapConfirmed(MotionEvent event) {
            Log.d(TAG, "+ onSingleTapConfirmed(event:" + event + ")");
            singleTapDetected = true;
            Log.d(TAG, "- onSingleTapConfirmed()");
            return true;
        }

        @Override
        public boolean onDoubleTap(MotionEvent event) {
            Log.d(TAG, "+ onDoubleTap(event:" + event + ")");
            doubleTapDetected = true;
            Log.d(TAG, "- onDoubleTap()");
            return true;
        }
    };

    private GestureDetector gestureDetector = new GestureDetector(getContext(), gestureListener);

    . . .
}

我跑了它的AVD作出的SurfaceView（GameView）一个单一的点击。结果
据LogCat中日志：

I ran it on AVD an made a single click on the SurfaceView (GameView).
According to LogCat logs:

03-11 14:19:51.171: D/GameView(4839): + onTouchEvent(event:MotionEvent { action=ACTION_DOWN, id[0]=0, x[0]=1071.0, y[0]=437.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=27223172, downTime=27223172, deviceId=0, source=0x1002 })
03-11 14:19:51.171: D/GameView(4839): - onTouchEvent()
03-11 14:19:51.171: D/GameActivity(4839): + onTouchEvent(event:MotionEvent { action=ACTION_DOWN, id[0]=0, x[0]=1071.0, y[0]=437.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=27223172, downTime=27223172, deviceId=0, source=0x1002 })
03-11 14:19:51.171: D/GameActivity(4839): - onTouchEvent()
03-11 14:19:51.299: D/GameActivity(4839): + onTouchEvent(event:MotionEvent { action=ACTION_UP, id[0]=0, x[0]=1071.0, y[0]=437.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=27223303, downTime=27223172, deviceId=0, source=0x1002 })
03-11 14:19:51.299: D/GameActivity(4839): - onTouchEvent()

有几个问题：

1. 为什么 SimpleOnGestureListener 不叫？ （即使 onTouchEvent（）被称为和presummably行 gestureDetector.onTouchEvent（事件）; 被执行死刑）

1. Why the SimpleOnGestureListener was not called? (Even though onTouchEvent() was called and presummably the line gestureDetector.onTouchEvent(event); was executed)

为什么GameActivity的 onTouchEvent（）获得 ACTION_DOWN 和 ACTION_UP ，但在GameView的 onTouchEvent（）只得到 ACTION_DOWN

Why the GameActivity's onTouchEvent() gets ACTION_DOWN and ACTION_UP, but the GameView's onTouchEvent() only gets ACTION_DOWN?

有些事情我已经试过

• 我实现了 GestureDetector 使用同一code中的 GameActivity 类，如上图所示和它的工作如预期，称 onSingleTapConfirmed（）

• I implemented the GestureDetector on the GameActivity class with the same code as shown above and it worked as expected, calling onSingleTapConfirmed()

在GameView，而不是一个私有成员 SimpleOnGestureListener ，创建了一个私人类GestureListener扩展SimpleOnGestureListener 和用它来构建 GestureDetector 。我看到的描述相同的行为，给听者没有呼叫。

In GameView, instead of a private member SimpleOnGestureListener, created a private class GestureListener extends SimpleOnGestureListener and used it to construct the GestureDetector. I see the same behavior as described, no call to the listener.

推荐答案

我调试的code到Android源$ C ​​$ C，GestureDetector类。这解释了为什么 SimpleOnGestureListener 不叫：

I debugged the code into the android source code, GestureDetector class. And this explains why SimpleOnGestureListener was not called:

• 的ACTION_DOWN被接收并产生内部TAP消息GestureDetector消息处理程序。


• 的处理程序将调用监听器 onSingleTapConfirmed（）仅在事件的不可以仍下降（！mStillDown ）


• 事件仍然下跌，因为从来没有收到ACTION_UP事件。

• The ACTION_DOWN is received and generates an internal TAP message to the GestureDetector message Handler.
• The Handler calls the listener onSingleTapConfirmed() only if the event is not still down (!mStillDown)
• The event is still down, because the ACTION_UP event was never received.

所以你看，这两个问题是相关的，当我发现为什么ACTION_UP不发我会解决这个问题！

So you see, the two questions are related, when I find out why ACTION_UP is not issued I will solve the problem!

修改

这样就完成了答案，现在它正在工作。

This completes the answer, now it is working.

• 到 super.onTouchEvent（）的调用在GameView回报假，因为超级类SurfaceView是查看，并返回假。这就是为什么ACTION_UP不会被调用


• 在GameActivity返回 super.onTouchEvent（）呼叫真正，这就是为什么ACTION_UP上GameActivity发出。

• The call to super.onTouchEvent() in GameView returns false, because the super class of SurfaceView is View, and it returns false. That's why ACTION_UP is never called
• The call to super.onTouchEvent() in GameActivity returns true, that's why ACTION_UP is issued on GameActivity.

的注：如果我设置的 GameView.setclickable（真）的然后的超。 onTouchEvent（）的返回的真正。的这也是一个可接受的解决方案的

现在我GameView code是：

Now my GameView code is:

@Override
public boolean onTouchEvent(MotionEvent event) {
    Log.d(TAG, "+ onTouchEvent(event:" + event + ")");
    gestureDetector.onTouchEvent(event);
    Log.d(TAG, "- onTouchEvent()");
    return true;
}

目前LogCat中日志是：

The current LogCat logs are:

03-11 16:32:06.629: D/GameView(5316): + onTouchEvent(event:MotionEvent { action=ACTION_DOWN, id[0]=0, x[0]=977.0, y[0]=414.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=35158623, downTime=35158623, deviceId=0, source=0x1002 })
03-11 16:32:06.629: D/GameView(5316): - onTouchEvent()
03-11 16:32:06.641: D/GameView(5316): + onTouchEvent(event:MotionEvent { action=ACTION_MOVE, id[0]=0, x[0]=978.0, y[0]=414.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=35158623, downTime=35158623, deviceId=0, source=0x1002 })
03-11 16:32:06.641: D/GameView(5316): - onTouchEvent()
03-11 16:32:06.772: D/GameView(5316): + onTouchEvent(event:MotionEvent { action=ACTION_UP, id[0]=0, x[0]=978.0, y[0]=414.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=35158772, downTime=35158623, deviceId=0, source=0x1002 })
03-11 16:32:06.772: D/GameView(5316): - onTouchEvent()
03-11 16:32:06.931: D/GestureListener(5316): + onSingleTapConfirmed(event:MotionEvent { action=ACTION_DOWN, id[0]=0, x[0]=977.0, y[0]=414.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=35158623, downTime=35158623, deviceId=0, source=0x1002 })
03-11 16:32:06.931: D/GestureListener(5316): - onSingleTapConfirmed()

这篇关于Android的GestureDetector与内SurfaceView SimpleOnGestureListener的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！