android 如何判读app应用是否拥有某种权限

"android.permission.CAMERA"表示要判断的权限，此处以相机权限为例说明

"com.zhengyuan.learningqrscan"表示项目的包名

//动态申请权限
    private void getPrimission() {
        PackageManager pm = getPackageManager();
        boolean permission = (PackageManager.PERMISSION_GRANTED ==
                pm.checkPermission("android.permission.CAMERA", "com.zhengyuan.learningqrscan"));
        if (permission) {
            //"有这个权限"
            Toast.makeText(MainActivity.this, "有权限", Toast.LENGTH_SHORT).show();
        } else {
            //"木有这个权限"
            //如果android版本大于等于6.0，权限需要动态申请
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                requestPermissions(new String[]{Manifest.permission.CAMERA}, 15);
            }
        }


    }

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