我需要帮助完成我的学校项目。我有两个活动-主要活动与图像视图和设置活动与两个单选按钮。我想在主要活动的图像改变时，我在设置活动单选按钮点击。这是我设置活动的代码：

private RadioGroup radioGroup;
private ImageView imageView;
private Integer []photos = {R.drawable.red, R.drawable.blue};

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

    this.imageView = (ImageView ) findViewById(R.id.imageView);
    this.radioGroup = (RadioGroup) findViewById(R.id.radioGroup);
    radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup radioGroup, int id) {
            RadioButton radioButton = (RadioButton) radioGroup.findViewById(id);
            int index = radioGroup.indexOfChild(radioButton);
            imageView.setImageResource(photos[index]);
        }
    });
}

谢谢你的回答。