Pass data from thread into Activity
I am want to pass data back from a Thread
to Activity
(which created the thread).
So I am doing like described on And开发者_Python百科roid documentation:
public class MyActivity extends Activity {
[ . . . ]
// Need handler for callbacks to the UI thread
final Handler mHandler = new Handler();
// Create runnable for posting
final Runnable mUpdateResults = new Runnable() {
public void run() {
updateResultsInUi();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
[ . . . ]
}
protected void startLongRunningOperation() {
// Fire off a thread to do some work that we shouldn't do directly in the UI thread
Thread t = new Thread() {
public void run() {
mResults = doSomethingExpensive();
mHandler.post(mUpdateResults);
}
};
t.start();
}
private void updateResultsInUi() {
// Back in the UI thread -- update our UI elements based on the data in mResults
[ . . . ]
}
}
Only one thing I am missing here - where and how should be defined mResults
so I could access it from both Activity
and Thread
, and also would be able to modify as needed? If I define it as final
in MyActivity
, I can't change it anymore in Thread
- as it is shown in example...
Thanks!
If you define mResults in the class and not the method, you can change it from either location. For example:
protected Object mResults = null;
(Use protected because it's faster)
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