java - Java中如何从另一个对象调用对象的方法？

Question

我有两门课:

MainActivity.java

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        new MyAsyncTask().execute("string");
    }

    public void setSomething(int param) {
        // ... some code here ...
    }
}

和

MyAsyncTask.java

public class MyAsyncTask extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... str) {
        return "Someting here";
    }

    @Override
    protected void onPostExecute(String jsonStr) {
         // how to call setSomething(param) from here?
    }
}

如何从 MyAsyncTask 调用 setSomething(param)？

Answer 1

将 MainActivity 的引用传递给 MyAsyncTask:

public class MyAsyncTask extends AsyncTask<String, Void, String>
{
    private MainActivity mainActivity;

    public MyAsyncTask(MainActivity mainActivity)
    {
        this.mainActivity = mainActivity;
    }
}

然后，每当在类 MainActivity 中创建 MyAsyncTask 实例时，传递 this (MainActivity 实例)到构造函数:

new MyAsyncTask(this).execute();