These days I'm working on simulating modal dialog in Android. I've googled a lot, there's much discussions but sadly there's not much options to get it modal. Here's some background,
Dialogs, Modal Dialogs and Blockin
Dialogs / AlertDialogs: How to "block execution" while dialog is up (.NET-style)
There's no straight way to get modal behavior, then I came up with 3 possible solutions,
1. Use a dialog-themed activity, like this thread said, but I still can't make main activity truly wait for dialog-activity return. Main activity turned to stop status and got restarted then.
2. Build one worker thread, and use thread synchronization. However, it's a huge refactoring job for my app, now I have a single main activity and a service both in main UI thread.
3. Take over event handling within a loop when there is a modal dialog up, and quit loop when dialog gets closed. Actually it's the way to build a real modal dialog like what it exactly does in Windows. I still haven't prototyped this way.
I'd still like to simulate it with a dialog-themed activity,
1. start dialog-activity by startActivityForResult()
2. get result from onActivityResult()
Here's some source
public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView v = new MyView(this);
setContentView(v);
}
private final int RESULT_CODE_ALERT = 1;
private boolean mAlertResult = false;
public boolean startAlertDialog() {
Intent it = new Intent(this, DialogActivity.class);
it.putExtra("AlertInfo", "This is an alert");
startActivityForResult(it, RESULT_CODE_ALERT);
// I want to wait right here
return mAlertResult;
}
@Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case RESULT_CODE_ALERT:
Bundle ret = data.getExtras();
mAlertResult = ret.getBoolean("AlertResult");
break;
}
}
}
The caller of startAlertDialog will block execution and expect returned result. But startAlertDialog returned immediately of course, and main activity went into STOP status while DialogActivity was up.
So the question is, how to make main activity really wait for result?
Thanks.
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