Authority list doesn't update in FilterDisplayTableView when the property changes

[vteague]

FilterDisplayTableView.cs is meant to bind to an instance of FilterChoices.cs.

I've implemented OnPropertyChanged in FilterChoices.cs (correctly I think), but FilterDisplayTableView.cs doesn't update.

For example, when the user clicks
Start drafting -> A public authority -> [chooses something] -> save -> next
we get a screen (which happens to be an instance of QuestionAskerPage) with the right authority list displayed in the FilterDisplayTableView at the top, after "Who should answer it?". This is correct.

But then if the user clicks on the list of authorities they've chosen, selects or deselects some, and clicks 'save,' we go back to the QuestionAskerPage (good), but the FilterDisplayTableView hasn't updated with the edited list of authorities (wrong). I'm pretty sure the underlying data is updating correctly, because if you go back and reload you get the correct, updated, version - it's just a question of getting the view to update as soon as the property changes.

Please fix FilterDisplayTableView so that when the SelectedAuthorities property of its FilterChoices binding changes, it updates its display of SelectedAuthorities.

I think if you're a Xamarin Forms pro you'll be able to fix this in about 5 minutes.