如何将屏幕宽度分成两部分以进行滑动手势

问题描述

我正在使用 Exoplayer 开发视频播放器应用程序并应用滑动手势来调节音量和亮度。顶部、底部、右侧、左侧的滑动手势运行良好。 但我想将宽度分为音量和亮度功能的两部分，建议我做额外的代码。 这是我的 OnSwipetouchListner.java 代码

 struct ContainerView: UIViewRepresentable {

        func makeUIView(context: Context) -> DonationCell {
            DonationCell()
        }

        func updateUIView(_ uiView: DonationCell,context: Context) {
        }
    }
}

下面的代码是在Main Activity中的实现

public class OnSwipetouchListener implements View.OnTouchListener {
private final GestureDetector gestureDetector;

public OnSwipetouchListener(Context ctx) {
    gestureDetector = new GestureDetector(ctx,new GestureListener());
}

@Override
public boolean onTouch(View v,MotionEvent event) {
    return gestureDetector.onTouchEvent(event);
}

private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
    private static final int SWIPE_THRESHOLD = 100;
    private static final int SWIPE_VELociTY_THRESHOLD = 100;

    @Override
    public boolean onDown(MotionEvent e) {
        return true;
    }

    ///below first one is downEvent second is moveEvent
    @Override
    public boolean onFling(MotionEvent e1,MotionEvent e2,float veLocityX,float veLocityY) {
        boolean result = false;
        try {
            float diffY = e2.getY() - e1.getY();
            float diffX = e2.getX() - e1.getX();
            if (Math.abs(diffX) > Math.abs(diffY)) {
                if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(veLocityX) > SWIPE_VELociTY_THRESHOLD) {
                    if (diffX > 0) {
                        onSwipeRight();
                    } else {
                        onSwipeLeft();
                    }
                    result = true;
                }
            } else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(veLocityY) > SWIPE_VELociTY_THRESHOLD) {
                if (diffY > 0) {
                    onSwipeBottom();
                } else {
                    onSwipetop();
                }
                result = true;
            }
        } catch (Exception exception) {
            exception.printstacktrace();
        }
        return result;
    }
}

public void onSwipeRight() {
}

public void onSwipeLeft() {
}

public void onSwipetop() {
}

public void onSwipeBottom() {
}}

解决方法

要检查屏幕的哪一部分被触摸（左侧部分或右侧部分），首先尝试在 onDown 中计算屏幕的宽度和高度：

screen_width = getResources().getDisplayMetrics().widthPixels;
screen_height = getResources().getDisplayMetrics().heightPixels;

创建 2 个布尔值：

private boolean isLeft;
private boolean isRight;

@Override
        public boolean onDown(MotionEvent event) {
            Log.d("TAG","onDown: ");
            screen_width = getResources().getDisplayMetrics().widthPixels;
            screen_height = getResources().getDisplayMetrics().heightPixels;
            
            if (event.getX() < (screen_width / 2)) {
                // isLeft means the left side is touched
                isLeft = true;
                isRight = false;

            } else if (event.getX() > (screen_width / 2)) {
                // isRight means the right side is touched
                isLeft = false;
                isRight = true;
            }
            // don't return false here
            // or else none of the other gestures will work
            return true;
        }

然后根据需要使用布尔值：

if (isRight) {

} else if (isLeft) {

}