问在手指触摸和弹出移动之间拖动弹出距离

EN

public class PopupDragUtility implements OnTouchListener {

ReaderLaunchActivity readerAct;
PopupWindow targetWindow;
private float dX = 0;
private float dY = 0;

public PopupDragUtility(ReaderLaunchActivity readerAct, PopupWindow targetWindow) {
    super();
    this.readerAct = readerAct;
    this.targetWindow = targetWindow;
}

@Override
public boolean onTouch(View p_v, MotionEvent p_event) {
    switch (p_event.getAction()) {
    case MotionEvent.ACTION_DOWN: {
        dX = p_event.getRawX();
        dY = p_event.getRawY();
        break;
    }
    case MotionEvent.ACTION_UP: {
        break;
    }

    case MotionEvent.ACTION_MOVE: {

        if (readerAct.deviceOrientation == Configuration.ORIENTATION_LANDSCAPE) {
            float newX = p_event.getRawX() - 390;
            float newY = p_event.getRawY();

            System.out.println("newX    " + newX);
            System.out.println("newY   " + newY);

            if (newX > -390 && newY > 75 && (newX + targetWindow.getWidth()) < readerAct.readerLayout.getWidth()
                    && (newY + targetWindow.getHeight()) < readerAct.readerLayout.getHeight()) {

                targetWindow.update((int) newX, (int) newY, -1, -1, true);

            }

        } else {
            float newX = p_event.getRawX() - 140;
            float newY = p_event.getRawY();

            System.out.println("newX    " + newX);
            System.out.println("newY   " + newY);

            if (newX > -140 && newY > 75 && (newX + targetWindow.getWidth()) < readerAct.readerLayout.getWidth()
                    && (newY + targetWindow.getHeight()) < readerAct.readerLayout.getHeight()) {

                targetWindow.update((int) newX, (int) newY, -1, -1, true);

            }
        }

        break;
    }
    }
    return true;
}

 and the pop up movement.I have temporary resolved this issue with the help      of some constants.But Can anyone suggest a solution without constants.  Here target window is the reference of the popup and reader layout is the

 reference of the entire screen.