Question

我知道如何检测双击和双指触摸事件，但我如何将这些结合起来反应，以便有人需要用两根手指双击？

默认情况下，Android长按可以作为第二种点击形式，但我特意寻找双指双击。

Answer 1

我想要一个简单且可重复使用的界面，它可以侦听两个手指双击并且表现得像GestureDetector。所以你可以像这样使用它（所有剪切和粘贴可运行的代码）：

public class Example extends Activity {
    SimpleTwoFingerDoubleTapDetector multiTouchListener = new SimpleTwoFingerDoubleTapDetector() {
        @Override
        public void onTwoFingerDoubleTap() {
            // Do what you want here, I used a Toast for demonstration
            Toast.makeText(Example.this, "Two Finger Double Tap", Toast.LENGTH_SHORT).show();
        }
    };

    // Override onCreate() and anything else you want

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if(multiTouchListener.onTouchEvent(event))
            return true;
        return super.onTouchEvent(event);
    }
}

我创建了SimpleTwoFingerDoubleTapDetector。（这是一个很长的名字，但它是描述性的。你可以将它重命名为你想要的任何东西。）将这个新文件保存在你的项目中或作为一个库：

public abstract class SimpleTwoFingerDoubleTapDetector {
    private static final int TIMEOUT = ViewConfiguration.getDoubleTapTimeout() + 100;
    private long mFirstDownTime = 0;
    private boolean mSeparateTouches = false;
    private byte mTwoFingerTapCount = 0;

    private void reset(long time) {
        mFirstDownTime = time;
        mSeparateTouches = false;
        mTwoFingerTapCount = 0;
    }

    public boolean onTouchEvent(MotionEvent event) {
        switch(event.getActionMasked()) {
        case MotionEvent.ACTION_DOWN:
            if(mFirstDownTime == 0 || event.getEventTime() - mFirstDownTime > TIMEOUT) 
                reset(event.getDownTime());
            break;
        case MotionEvent.ACTION_POINTER_UP:
            if(event.getPointerCount() == 2)  
                mTwoFingerTapCount++;
            else 
                mFirstDownTime = 0;
            break;
        case MotionEvent.ACTION_UP:
            if(!mSeparateTouches)
                mSeparateTouches = true;
            else if(mTwoFingerTapCount == 2 && event.getEventTime() - mFirstDownTime < TIMEOUT) {
                onTwoFingerDoubleTap();
                mFirstDownTime = 0;
                return true;
            }
        }               

        return false;
    }

    public abstract void onTwoFingerDoubleTap();
}

首先，关于Android的一些注意事项（一键式） GestureDetector ：

Android的onDoubleTap()事件使用ViewConfiguration中的标准超时值。我指的是同一时间。
他们测量从第一次点击手指向下事件到第二次点按手指向下事件所经过的时间，然后广播onDoubleTap()和onDoubleTapEvent()。
- onDoubleTap()仅在第二次敲击手指发生事件时触发。
- onDoubleTapEvent()会针对每个操作触发：向下，向上移动。

关于 SimpleTwoFingerDoubleTapDetector 的几点说明：

我的超时是从第一个手指向下事件到最后一个手指向上事件测量的，以防止错误的双击通知。我为默认的ViewConfiguration双击超时添加了一些额外的时间来解决这个问题。
Android的GestureDetector测量slop（两个水龙头相隔多远）。我没有看到这里的需要，也没有检查每个水龙头上两个手指之间的距离。
我只播放了一个事件onTwoFingerDoubleTap()。

最后说明： 您可以轻松更改此操作，使其行为类似于OnTouchListener：

更改SimpleTwoFingerDoubleTapDetector的定义：

public abstract class SimpleTwoFingerDoubleTapListener implements OnTouchListener {

添加新的类变量：
```
private View mFirstView;
```

更改ACTION_DOWN案例：

case MotionEvent.ACTION_DOWN:
    if(mFirstDownTime == -1 || mFirstView != v || hasTimedOut(event.getEventTime())) {
        mFirstView = v;
        reset(event.getDownTime());
    }
    break;

在mFirstView案例中传递ACTION_UP：
```
onTwoFingerDoubleTap(mFirstView);
```
最后，更改onTwoFingerDoubleTap()方法以反映点击了哪个视图：
```
public abstract void onTwoFingerDoubleTap(View v);
```

Answer 2

这是我创建的双击侦听器，用于检测双指双击。

使用的变量：

private GestureDetector gesture;
private View.OnTouchListener gestureListener;
boolean click1 = false;
boolean click2 = false;
long first = 0;
long second = 0;

在活动的onCreate()中注册触摸事件：

gesture = new GestureDetector(getApplicationContext(), new SimpleOnGestureListener(){
    public boolean onDown(MotionEvent event) {
        return true;
    }
});
gestureListener = new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return gesture.onTouchEvent(event);
    }
};

活动内onCreate()之外：

@Override
public boolean onTouchEvent(MotionEvent event) {   
    try {
        int action = event.getAction() & MotionEvent.ACTION_MASK;
        //capture the event when the user lifts their fingers, not on the down press
        //to make sure they're not long pressing
        if (action == MotionEvent.ACTION_POINTER_UP) {
            //timer to get difference between clicks
            Calendar now = Calendar.getInstance();

            //detect number of fingers, change to 1 for a single-finger double-click, 3 for a triple-finger double-click, etc.
            if (event.getPointerCount() == 2) {
                if (!click1) {
                    //if this is the first click, then there hasn't been a second
                    //click yet, also record the time
                    click1 = true;
                    click2 = false;
                    first = now.getTimeInMillis(); 
                } else if (click1) {
                    //if this is the second click, record its time 
                    click2 = true;
                    second = now.getTimeInMillis();

                    //if the difference between the 2 clicks is less than 500 ms (1/2 second)
                    //Math.abs() is used because you need to be able to detect any sequence of clicks, rather than just in pairs of two
                    //(e.g. click1 could be registered as a second click if the difference between click1 and click2 > 500 but
                    //click2 and the next click1 is < 500)
                    if (Math.abs(second-first) < 500) {

                        //do something!!!!!!

                    } else if (Math.abs(second-first) >= 500) {
                        //reset to handle more clicks
                        click1 = false;
                        click2 = false;
                    }
                }
            }
        }
    } catch (Exception e){

    }
    return true;
}

如何在Android中实现双指双击？

2 个答案: