处理触摸事件 - onInterceptTouchEvent和onTouchEvent

Question

我希望能够在屏幕上的任何位置滑动以调用某个功能.但我也有Buttons,Linear Layouts因为我希望能够点击.如果我刷上Button我想 onInterceptTouchEvent给Intercept在调用Button的onTouchEvent和进行刷卡操作.如果我只是点击一个Button我不希望onInterceptTouchEvent被调用.相反,我希望Button的onTouchEvent要调用和执行Button click

但是当我尝试实现时,我会遇到错误onInterceptTouchEvent.

这是我的代码:

public class Game extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.game_activity);

   //other code....
}
}

@Override
public boolean onInterceptTouchEvent(MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            break;
        case MotionEvent.ACTION_CANCEL:
        case MotionEvent.ACTION_UP:
            swipeScreen(); //if action recognized as swipe then swipe
            break;
        case MotionEvent.ACTION_MOVE:
            float x = event.getX();
            float y = event.getY();
            float xDelta = Math.abs(x - mLastX);
            float yDelta = Math.abs(y - mLastY);

            if (yDelta > xDelta) {
                return true;
            }
            break;
    }

    return false;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    ButtonOnClick(); //if not a swipe, then button click
    return true;
}

首先错误说: The method onInterceptTouchEvent(MotionEvent) of type Game must override or implement a supertype method

然后,而不是return true我将代码更改为:return super.onInterceptTouchEvent(event) 但后来我得到一个错误说:The method onInterceptTouchEvent(MotionEvent) is undefined for the type Activity

有人可以帮忙吗？

Answer 1

请注意,这onInterceptTouchEvent()是来自ViewGroup类的方法,而不是来自Activity.

您可以通过实现移动你的逻辑所期望的行为onInterceptTouchEvent()来dispatchTouchEvent(MotionEvent ev).记得调用超类实现dispatchTouchEvent(MotionEvent ev)来处理应该正常处理的事件.

另请注意,只有当delta大于触摸斜率的系统常量时,才应将移动视为滑动.我建议确保用户通过测试yDelta / 2 > xDelta而不是按照您想要的方向滑动yDelta > xDelta.

public class Game extends Activity {
    private int mSlop;
    private float mDownX;
    private float mDownY;
    private boolean mSwiping;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.game_activity);

        ViewConfiguration vc = ViewConfiguration.get(this)
        mSlop = vc.getScaledTouchSlop();

       //other code....
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mDownX = ev.getX();
                mDownY = ev.getY();
                mSwiping = false;
                break;
            case MotionEvent.ACTION_CANCEL:
            case MotionEvent.ACTION_UP:
                if(mSwiping) {
                    swipeScreen(); //if action recognized as swipe then swipe
                }
                break;
            case MotionEvent.ACTION_MOVE:
                float x = ev.getX();
                float y = ev.getY();
                float xDelta = Math.abs(x - mDownX);
                float yDelta = Math.abs(y - mDownY);

                if (yDelta > mSlop && yDelta / 2 > xDelta) {
                    mSwiping = true;
                    return true;
                }
                break;
        }

        return super.dispatchTouchEvent(ev);
    }
}