Android 学习手册

if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
    ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, REQUEST_CAMERA);
} else {
    // 已有权限
}

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    if (requestCode == REQUEST_CAMERA && grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
        // 权限授予
    }
}