Proper way of dismissing DialogFragment while application is in background

Question

I started using DialogFragment, because they are working nicely through orientation changes, and stuff. But there is nasty problem I encountered.

I have AsyncTask that shows progress DialogFragment and dismisses it onPostExecute. Everything works fine, except when onPostExecute happens while application is in background (after pressing Home button, for example). Then I got this error on DialogFragment dismissing - "Can not perform this action after onSaveInstanceState". Doh. Regular dialogs works just fine. But not FragmentDialog.

So I wonder, what is the proper way of dismissing DialogFragment while application is in background? I haven't really worked with Fragments a lot, so I think that I'm just missing something.

Answer 1

DialogFragment has a method called dismissAllowingStateLoss()

Answer 2

This is what I did (df == dialogFragment):

Make sure that you call the dialog this way:

df.show(getFragmentManager(), "DialogFragment_FLAG");

When you want to dismis the dialog make this check:

if (df.isResumed()){
  df.dismiss();
}
return;

Make sure that you have the following in the onResume() method of your fragment (not df)

@Override
public void onResume(){
  Fragment f = getFragmentManager().findFragmentByTag("DialogFragment_FLAG");
  if (f != null) {
    DialogFragment df = (DialogFragment) f;
    df.dismiss();
  }
  super.onResume();
}   

This way, the dialog will be dismissed if it's visible.. if not visible the dialog is going to be dismisded next the fragment becomes visible (onResume)...

Answer 3

This is what I had to do to achieve what you want: I have a Fragment activity on which i was showing a dialog fragment named fragment_RedemptionPayment which is globally declared at the top. The following code dismisses the DialogFragment if it was showing before the activity goes in background and comes back in foreground.

     @Override
        public void onResume() {
            super.onResume();        
            if(fragment_RedemptionPayment.isVisible()){
                fragment_RedemptionPayment.dismiss();
            }
}

Answer 4

A solution that might work is setting Fragment.setRetainInstance(true) in your dialogfragment, but that's not the prettiest of fixes.

Sometimes I have noticed that I have to queue up my dialog actions to let the framework restore the state first. If you can get hold of the current Looper (Activity.getMainLooper()) and wrap that in a Handler you could try passing your dismissal to the back of the queue by posting a runnable on that queue.

I often end up using a separate fragment that it retaininstance(true) that has a ResultReceiver. So i pass on that result receiver to my jobs and handle callbacks in its onReceive (often as a router for other receivers). But that might be a bit more work than it is worth if you are using async tasks.