前言

本文例子实现了点击显示悬浮窗口,同时窗口可播放视频,拖动位置,点击关闭及返回APP页面,通过例子来讲述悬浮窗口实现原理及细节处理,效果图如下所示:

原理

  1. WindowManagerView视图进行添加、移除、更新处理;
  2. WindowManager.LayoutParams对窗口参数进行一系列设置。

实现

  1. 首先,需要添加相对应悬浮窗权限:
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
  1. Activity页面中,需要判断悬浮窗权限是否获取,如果未曾获取,需要跳转系统页,进行对应的授权操作:
public boolean requestOverlayPermission() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (!Settings.canDrawOverlays(this)) {
            Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + getPackageName()));
            startActivityForResult(intent, REQUEST_OVERLAY_CODE);
            return true;
        } else {
            return false;
        }
    }
    return false;
}
  1. 获取权限后,我们可以首先初始化我们要显示的视图,并且设置相对应的事件,这里我们采用了VideoView进行简单的视频播放,并且设置悬浮窗关闭及返回前台的操作:
private View initFloatView() {
    View view = View.inflate(this, R.layout.view_floating_window, null);
    // 设置视频封面
    final ImageView mThumb = (ImageView) view.findViewById(R.id.thumb_floating_view);
    Glide.with(this).load(R.drawable.thumb).into(mThumb);
    // 悬浮窗关闭
    view.findViewById(R.id.close_floating_view).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            mFloatingWindow.dismiss();
        }
    });
    // 返回前台页面
    view.findViewById(R.id.back_floating_view).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            mFloatingWindow.setTopApp(FloatingWindowActivity.this);
        }
    });
    final VideoView videoView = view.findViewById(R.id.video_view);
    //视频内容设置
  videoView.setVideoPath("https://stream7.iqilu.com/10339/article/202002/18/2fca1c77730e54c7b500573c2437003f.mp4");
    // 视频准备完毕,隐藏正在加载封面,显示视频
    videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
        @Override
        public void onPrepared(MediaPlayer mp) {
            mThumb.setVisibility(View.GONE);
        }
    });
    // 循环播放
    videoView.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mp) {
            videoView.start();
        }
    });
    // 开始播放视频
    videoView.start();
    return view;
}
  1. 通过获取窗口管理WindowManager,设置悬浮窗口参数WindowManager.LayoutParams后,就可以通过WindowManageraddView方法,生成对应视图的悬浮窗口:
public void showFloatingWindowView(Context context, View view) {
    // 悬浮窗显示视图
    mShowView = view;
    // 获取系统窗口管理服务
    mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    // 悬浮窗口参数设置及返回
    mFloatParams = getParams();
    // 设置窗口触摸移动事件
    mShowView.setOnTouchListener(new FloatViewMoveListener());
    // 悬浮窗生成
    mWindowManager.addView(mShowView, mFloatParams);
}
  1. WindowManager.LayoutParams参数设置,主要设置悬浮窗口类型为WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
private WindowManager.LayoutParams getParams() {
    WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();
    //设置悬浮窗口类型
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        layoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
    } else {
        layoutParams.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
    }
    //设置悬浮窗口属性
    layoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
            | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
            | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
            | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR
            | WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH;
    //设置悬浮窗口透明
    layoutParams.format = PixelFormat.TRANSLUCENT;
    //设置悬浮窗口长宽数据
    layoutParams.width = 600;
    layoutParams.height = 340;
    //设置悬浮窗显示位置
    layoutParams.gravity = Gravity.START | Gravity.TOP;
    layoutParams.x = 100;
    layoutParams.y = 100;
    return layoutParams;
}
  1. 窗口触摸移动事件,主要通过获取触摸位置,通过WindowManagerupdateViewLayout方法设置悬浮窗口的参数,进行窗口视图位置更新:
private class FloatViewMoveListener implements View.OnTouchListener {

    //开始触控的坐标,移动时的坐标(相对于屏幕左上角的坐标)
    private int mTouchStartX;
    private int mTouchStartY;
    //开始时的坐标和结束时的坐标(相对于自身控件的坐标)
    private int mStartX, mStartY;
    //判断悬浮窗口是否移动,这里做个标记,防止移动后松手触发了点击事件
    private boolean isMove;

    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
        int action = motionEvent.getAction();
        int x = (int) motionEvent.getX();
        int y = (int) motionEvent.getY();
        switch (action) {
            case MotionEvent.ACTION_DOWN:
                isMove = false;
                mTouchStartX = (int) motionEvent.getRawX();
                mTouchStartY = (int) motionEvent.getRawY();
                mStartX = x;
                mStartY = y;
                break;
            case MotionEvent.ACTION_MOVE:
                int mTouchCurrentX = (int) motionEvent.getRawX();
                int mTouchCurrentY = (int) motionEvent.getRawY();
                mFloatParams.x += mTouchCurrentX - mTouchStartX;
                mFloatParams.y += mTouchCurrentY - mTouchStartY;
                mWindowManager.updateViewLayout(mShowView, mFloatParams);
                mTouchStartX = mTouchCurrentX;
                mTouchStartY = mTouchCurrentY;
                float deltaX = x - mStartX;
                float deltaY = y - mStartY;
                if (Math.abs(deltaX) >= 5 || Math.abs(deltaY) >= 5) {
                    isMove = true;
                }
                break;
            case MotionEvent.ACTION_UP:
                break;
            default:
                break;
        }
        //如果是移动事件不触发OnClick事件,防止移动的时候一放手形成点击事件
        return isMove;
    }
}
  1. 关闭悬浮窗,调用WindowManagerremoveView方法即可:
public void dismiss() {
    if (mWindowManager != null && mShowView != null) {
        mWindowManager.removeView(mShowView);
    }
}
  1. 悬浮窗点击返回前台方法:
public void setTopApp(Context context) {
    //获取ActivityManager
    ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    //获得当前运行的task(任务)
    List<ActivityManager.RunningTaskInfo> taskInfoList = null;
    if (activityManager != null) {
        taskInfoList = activityManager.getRunningTasks(100);
    }
    if (taskInfoList != null) {
        for (ActivityManager.RunningTaskInfo taskInfo : taskInfoList) {
            //找到本应用的 task,并将它切换到前台
            if (taskInfo.topActivity != null && taskInfo.topActivity.getPackageName().equals(context.getPackageName())) {
                activityManager.moveTaskToFront(taskInfo.id, 0);
                break;
            }
        }
    }
}

关于悬浮窗的一些基本操作到这里就基本结束了