android studio创建悬浮窗

第一步：创建一个项目。

第二步：创建一个service class，继承 Service

public class MyService extends Service {
    private static final String TAG = "MyService";

    //要引用的布局文件.
    ConstraintLayout toucherLayout;
    //布局参数.
    WindowManager.LayoutParams params;
    //实例化的WindowManager.
    WindowManager windowManager;

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

    @Override
    public void onCreate() {
        super.onCreate();
        Log.d(TAG, "into MyService onCreate");
        //OnCreate中来生成悬浮窗.
        createToucher();
    }

    private void createToucher() {
        //赋值WindowManager&LayoutParam.
        params = new WindowManager.LayoutParams();
        windowManager = (WindowManager) getApplication().getSystemService(Context.WINDOW_SERVICE);
        //设置type.系统提示型窗口，一般都在应用程序窗口之上.
        params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
        //设置效果为背景透明.
        //params.format = PixelFormat.RGBA_8888;
        //设置flags.不可聚焦及不可使用按钮对悬浮窗进行操控.
        params.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;

        //设置窗口初始停靠位置.
        params.gravity = Gravity.TOP | Gravity.LEFT;
        params.x = 0;
        params.y = 0;

        //设置悬浮窗口长宽数据.
        //注意，这里的width和height均使用px而非dp.这里我偷了个懒
        //如果你想完全对应布局设置，需要先获取到机器的dpi
        //px与dp的换算为px = dp * (dpi / 160).
        params.width = 200;
        params.height = 200;

        LayoutInflater inflater = LayoutInflater.from(getApplication());
        //获取浮动窗口视图所在布局.
        toucherLayout = (ConstraintLayout) inflater.inflate(R.layout.activity_main, null);
        //添加toucherlayout
        windowManager.addView(toucherLayout, params);
    }
}

第三步：注册我们创建的Service，并相应添加权限

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

<application
        ....
        <service android:name=".MyService" />
</application>

第四步：启动Service

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.activity_main);

        if (Build.VERSION.SDK_INT >= 23) {
            if (Settings.canDrawOverlays(MainActivity.this)) {
                Intent intent = new Intent(MainActivity.this, MyService.class);
                Toast.makeText(MainActivity.this, "已开启Toucher", Toast.LENGTH_SHORT).show();
                startService(intent);
                finish();
            } else {
                //若没有权限，提示获取.
                Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);
                Toast.makeText(MainActivity.this, "需要取得权限以使用悬浮窗", Toast.LENGTH_SHORT).show();
                startActivity(intent);
            }
        } else {
            //SDK在23以下，不用管.
            Intent intent = new Intent(MainActivity.this, MyService.class);
            startService(intent);
            finish();
        }
    }

最后，看下结果：

github:

https://github.com/C11761726/Corner.git