android - 使用 onInterceptTouchEvent() 时检测触摸事件

Question

我问这个相当复杂的问题，希望能从您那里得到一些想法。

事情是这样的:我创建了一个自定义 ListView 类，上面那个:

public class FolderListView extends ListView {

    private float xDistance, yDistance, lastX, lastY;
    private int folder_index;
    private FolderViewInterface openFolder;

    // private boolean swiping = false;

    // If built programmatically
    public FolderListView(Context context) {
        super(context);
    }

    // This example uses this method since being built from XML
    public FolderListView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    // Build from XML layout
    public FolderListView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {

        switch (ev.getAction()) {

        case MotionEvent.ACTION_UP:
            // if (swiping == false) {

            //if (xDistance > yDistance)
            //  return false;
        //  else {
                folder_index = pointToPosition((int) lastX, (int) lastY);
            //  Toast.makeText(getContext(),
            //          "You pressed a folder with index: " + folder_index,
            //          Toast.LENGTH_SHORT).show();
        //  }
            HomeScreenFragment f = new HomeScreenFragment();
            openFolder = (FolderViewInterface) f;
            openFolder.onFolderOpened(folder_index);
            // }
            // swiping = false;
            break;

        case MotionEvent.ACTION_DOWN:
            // swiping = false;
            xDistance = yDistance = 0f;
            lastX = ev.getX();
            lastY = ev.getY();
            break;
        case MotionEvent.ACTION_MOVE:
            // swiping = true;
            final float curX = ev.getX();
            final float curY = ev.getY();
            xDistance += Math.abs(curX - lastX);
            yDistance += Math.abs(curY - lastY);
            lastX = curX;
            lastY = curY;
            if (xDistance > yDistance)
                return false;
        }

        return super.onInterceptTouchEvent(ev);

    }

}

我正在寻找正确检测触摸事件的方法。我想通过触摸打开另一个 fragment ，但现在 fragment 是通过触摸和滑动打开的。

我使用了 onInterceptTouchEvent，因为我的列表中的元素是 viewpager，它们在滚动时表现不正常。

我需要某种逻辑来检测滑动而不执行这部分:

HomeScreenFragment f = new HomeScreenFragment();
            openFolder = (FolderViewInterface) f;
            openFolder.onFolderOpened(folder_index);

仅当事件是触摸事件而不是滑动事件时。

非常感谢任何类型的建议/帮助，如果您需要更多详细信息，请告诉我。

谢谢!

Answer 1

我根据 PRESSED_STATE_DURATION 花费 时间 125

试试这个

//Declare as instance variables
int oldX,oldY,newX,newY;
//State the minimum distance of swipe that you forgive the user for ;)
int distance = 10;
int time = 125;
boolean cancel = false;
case MotionEvent.ACTION_DOWN:
cancel = false;
//Get x and y of touch
oldX = ev.getX();
oldY = ev.getY();
startActionTimer();

case MotionEvent.ACTION_MOVE:
//Get x and y of touch
newX = ev.getX();
newY = ev.getY();

case MotionEvent.ACTION_UP:
cancel = true;

private void startActionTimer(){
        //time is pressed state duration
          new CountDownTimer(time, time) {
             public void onTick(long millisUntilFinished) {}

             public void onFinish() {
                //Time to do our action!!!
                // please consider
                if((Math.abs(newX - oldX )< distance) && (Math.abs(newY - oldY ) <distance)){
                    if(cancel == false){
                    // Now its a touch so do your action
                    }
                }
             }
          }.start();
     }

注意:请使用所有变量作为类变量(实例变量)以避免出现问题。因为有时我会遇到值未正确更新的奇怪情况

或

你为什么不试试 gesture detection

并覆盖onSingleTapUp方法