What is the correct way to update a TextView after a callback in the following scenario:
I have an activity that extends ListActivity. At some point that activity creates an AlertDialog to allow the user the option of filtering the list for items that contain a certain String (because the unfiltered list might be too long to scroll through it conveniently). My AlertDialog has, in addition to an OK and Cancel button, an EditText so the user can enter the String to use for filtering, and two radio buttons to select whether we should filter for list items that start with the specified String or merely contain the specified String. I have listeners set up for any changes to the EditText or RadioButtons so that I can cause the list to be reloaded based on the revised filtering criteria. All this is working fine with no problems. I can see the list changing behind the AlertDialog as I enter characters into the EditText. The problem is this. I also want to have a TextView that displays "(X items found)" after each reloading of the list, so the user can know when he has sufficiently narrowed the search so he can quit the AlertDialog and then pick from the (reduced) set of items now in the list. One other complication is that the reloading of the list involves a callback on a worker thread. You see, the list is a list of Dropbox files, and the asynchronous load is necessary because it might involve an Internet access. The callback is actually from a library provided by Dropbox. Therefore the place where the reloading (and item counting) is done is not the UI thread, so I can't update a TextView from there. I am familiar with Handlers and posting from threads, but there is a problem with that too. The Handler would be owned by the Activity, not by the AlertDialog, which could be dismissed before the asynchronous reload occurs. Will there be a problem if a post is made to start a Runnable that updates the TextView that was in the AlertDialog if that AlertDialog, and therefore the TextView inside it, has been destroyed? What if I define a strong reference in the Activity to the TextView, and the Runnable that is triggered by the asynchronous Dropbox operation just calls setText on that reference? Will that do anything bad if the Runnable is invoked after the AlertDialog is dismissed? What is the clean way of doing this? -Robert Scott Hopkins, MN -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/android-developers. To view this discussion on the web visit https://groups.google.com/d/msgid/android-developers/e79ac507-3ba7-4fca-8ab7-456abef374d3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
