miactivity.java

public class MiActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
	
		MiAsyncTask task = new MiAsyncTask(new Callback() {
	    
		    	public void finished() {
		        	Toast.makeText(MiActivity.this, “Tarea terminada.”, Toast.LENGTH_SHORT).show();
			}
	
		});
		task.execute((Void) null);
	}

}