Wpf listbox observablecollection not updating

🙂 No, you are not lost in your path to enlightenment. More specifically, you are binding to a collection of Person objects (namely an Observable Collection) that, in turn, implements the IList interface.The binding engine will automatically generate a List Collection View for such a collection.

Jedoch dynamische Bindungen einrichten, sodass Einfüge- oder Löschvorgänge in der Sammlung aktualisieren die UI automatisch die Sammlung implementieren muss die INotify Collection Changed Schnittstelle. NET Framework Verfügbar seit 3.0 Portierbare Klassenbibliothek Unterstützt in: portierbare .

Wenn Sie ein erweitertes Szenario und eine eigene Auflistung implementieren möchten, sollten Sie verwenden IList, stellt eine nicht generische Auflistung von Objekten, die einzeln nach Index zugegriffen werden kann.

For example, if the Bart character was the current item before it was removed from the collection, that state will be lost.

If this is important to your scenario, you must add additional code around the remove/re-add routine to save and restore currency.

Furthermore, when a Refresh() occurs within the view, it raises a Collection Changed notification and supplies the Action as “Reset”.

The Item Container Generator for the List Box receives this notification and responds by discarding all the existing visuals for the items.

Such a routine would need to move existing items to their new locations in the view, add items that were not previously present, and remove items that should no longer be present.

All of these changes would need to be made per the view’s sorting, grouping, and filter criteria.

Here is what the List Box declaration might look like: The image below depicts our List Box with grouping and sorting.

You can download the sample for this post to see the complete item template, item container style, and group item style.

Dynamically Updating Items is Problematic Ideally, applying a sort order to a Collection View would result in a grouped and sorted view of the collection that is fully maintained even when items within the collection are changed.

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