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Android Threads and Services Threads in Android Extending Thread

Cameron Stewart
Cameron Stewart
18,041 Points
Posted by Cameron Stewart
Cameron Stewart
18,041 Points

Scoping with Threads

I am not sure how to complete this code challange. If we extend a Thread, how do we pass back the result of twitterClient.update() to the Main activity;

public class MainActivity extends Activity {

public class TwitterThread extends Thread{

    final TwitterClient twitterClient = new TwitterClient();
    @Override
    public void run() {
        twitterClient.update();
    }
}
@Override
public void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.activity_main);

    TwitterThread t = new TwitterThread();
    t.setName("TwitterThread");
    t.start();
}

}

MainActivity.java 
public class MainActivity extends Activity {

    public class TwitterThread extends Thread{

        final TwitterClient twitterClient = new TwitterClient();
        @Override
        public void run() {
            twitterClient.update();
        }
    }
    @Override
    public void onCreate(Bundle savedInstanceState) {
        setContentView(R.layout.activity_main);

        TwitterThread t = new TwitterThread();
        t.setName("TwitterThread");
        t.start();
    }
}

1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

The problem is that you've moved the line defining the twitterClient variable inside the inner class. The code should look like this:

public class MainActivity extends Activity {
    final TwitterClient twitterClient = new TwitterClient();

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

      TwitterThread t = new TwitterThread();
      t.setName("TwitterThread");
      t.start();
    }

    public class TwitterThread extends Thread {
      @Override
      public void run() {
        twitterClient.update();
      } 
    }
}
Cameron Stewart
Cameron Stewart
18,041 Points
Cameron Stewart
Cameron Stewart
18,041 Points

Thanks Kourosh!

I didnt understand that Inner classes had scope of the external class :S