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我在 ListView 上有一个自定义 Swipe 事件，当我从左到右或从右到左滑动时应该触发该事件。我已经得到了整洁和工作，但有一个问题：当我尝试滚动时自然发生的 Fling 事件现在不再生效（我稍后会解释）。如何手动重新创建 Fling 事件？我正在使用的代码如下：

刷卡类：

public class Swipe implements SwipeInterface {

public Swipe() {}

@Override
public void bottom2top(View v) {
    //Help!
}

@Override
public void left2right(View v) {
    //Does logic here
}

@Override
public void right2left(View v) {
    //Does logic here
}

@Override
public void top2bottom(View v) {
    //Help!
}

}

自定义检测器类。这个类主要检查滑动的距离：

public class ActivitySwipeDetector implements View.OnTouchListener {

static final String logTag = "ActivitySwipeDetector";
private Swipe swipe;
static final int MIN_DISTANCE = 200;
private float downX, downY, upX, upY;

public ActivitySwipeDetector(Swipe swipe) {
    this.swipe = swipe;
}

public void onRightToLeftSwipe(View v) {
    Log.i(logTag, "RightToLeftSwipe!");
    swipe.right2left(v);
}

public void onLeftToRightSwipe(View v) {
    Log.i(logTag, "LeftToRightSwipe!");
    swipe.left2right(v);
}

public void onTopToBottomSwipe(View v) {
    Log.i(logTag, "onTopToBottomSwipe!");
    swipe.top2bottom(v);
}

public void onBottomToTopSwipe(View v) {
    Log.i(logTag, "onBottomToTopSwipe!");
    swipe.bottom2top(v);
}

public boolean onTouch(View v, MotionEvent event) {
    switch (event.getAction()) {
    case MotionEvent.ACTION_DOWN: {
        downX = event.getX();
        downY = event.getY();
        return true;
    }
    case MotionEvent.ACTION_UP: {
        upX = event.getX();
        upY = event.getY();

        float deltaX = downX - upX;
        float deltaY = downY - upY;

        // swipe horizontal?
        if (Math.abs(deltaX) > MIN_DISTANCE) {
            // left or right
            if (deltaX < 0) {
                this.onLeftToRightSwipe(v);
                return true;
            }
            if (deltaX > 0) {
                this.onRightToLeftSwipe(v);
                return true;
            }
        } else {
            Log.i(logTag, "Swipe was only " + Math.abs(deltaX) + " long, need at least " + MIN_DISTANCE);
        }

        // swipe vertical?
        if (Math.abs(deltaY) > MIN_DISTANCE) {
            // top or down
            if (deltaY < 0) {
                this.onTopToBottomSwipe(v);
                return true;
            }
            if (deltaY > 0) {
                this.onBottomToTopSwipe(v);
                return true;
            }
        } else {
            Log.i(logTag, "Swipe was only " + Math.abs(deltaX) + " long, need at least " + MIN_DISTANCE);
        }
    }
    }
    return false;
}

}

最后，这是我为实现自定义监听器所做的：

Swipe swipe = new Swipe();
ActivitySwipeDetector detector = new ActivitySwipeDetector(swipe);
listview.setOnTouchListener(detector);

同样，它运行良好，我仍然可以在 ListView 上实现 OnItemClickListener，但由于 Swipe 类中覆盖了 bottom2top 和 top2bottom 方法，它不再执行任何“滚动滚动”。所以问题是我如何再次“创建” Fling 滚动？我的猜测是我必须替换我标记为“帮助！”的代码。有东西，但我不知道是什么。

请帮忙？

4

1 回答 1

1

为什么不使用GestureDetector来检测滑动动作。

于 2013-06-11T08:17:29.520 回答