Android 开发：如何创建全屏透明悬浮窗，并实现触摸穿透功能？

要实现满足以上需求的悬浮窗，可以使用以下代码：

public class FloatingWindowService extends Service implements View.OnTouchListener {

    private WindowManager windowManager;
    private WindowManager.LayoutParams params;
    private View floatingView;
    private float touchX, touchY;

    @Override
    public void onCreate() {
        super.onCreate();

        windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

        floatingView = LayoutInflater.from(this).inflate(R.layout.floating_window_layout, null);

        params = new WindowManager.LayoutParams(
                WindowManager.LayoutParams.MATCH_PARENT,
                WindowManager.LayoutParams.MATCH_PARENT,
                WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
                WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL |
                        WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE |
                        WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN |
                        WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS,
                PixelFormat.TRANSPARENT);

        params.gravity = Gravity.TOP | Gravity.LEFT;
        params.x = 0;
        params.y = 0;

        floatingView.setOnTouchListener(this);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if (floatingView != null) {
            windowManager.addView(floatingView, params);
        }
        return START_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (floatingView != null) {
            windowManager.removeView(floatingView);
        }
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            touchX = event.getRawX();
            touchY = event.getRawY();
        }
        return false;
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

这段代码创建了一个悬浮窗的服务，通过在 onStartCommand 方法中将悬浮窗添加到 WindowManager 中。设置 WindowManager.LayoutParams 的一些属性可以实现悬浮窗的全屏透明效果，并且不影响用户操作悬浮窗下面的界面。在 onTouch 方法中记录触摸位置，返回 false 可以使触摸事件穿透悬浮窗正常操作下面的界面。

请确保在 AndroidManifest.xml 文件中添加以下权限：

<uses-permission android:name='android.permission.SYSTEM_ALERT_WINDOW' />

然后在你的 Activity 中启动悬浮窗服务：

Intent intent = new Intent(this, FloatingWindowService.class);
startService(intent);

这样就可以实现满足你需求的悬浮窗了。