解决android6.0打开摄像头"Failed to connect to camera service"的问题

android6.0使用camera.open()时需要在onCreate()里面添加如下代码，否则会报错"Failed to connect to camera service"：

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {            if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {                requestPermissions(new String[] {Manifest.permission.CAMERA}, 1);            }        }