void ITrackedList_CollectionChanged(object sender, TrackedListChangedEventArgs <TId, TTrackedModel> e)
{
if (e.ChangeEvent == TrackedListChangeEvent.Select)
{
// Update selection on grid control.
var trackedListSelectedItem = e.NewItems?.FirstOrDefault();
if (trackedListSelectedItem == null)
{
if (this.SelectedItem != null)
{
this.SelectedItem = null;
}
}
else
{
if (this.SelectedItem == null || !this.SelectedItem.Id.Equals(trackedListSelectedItem.Id))
{
var newStartingIndex = e.NewStartingIndex;
if (newStartingIndex > 0 && newStartingIndex < this.Items.Count)
{
this.SelectedItem = this.Items[newStartingIndex];
}
}
}
}
else
{
// Update observable collection, that is bound to grid, based on changes to shared data service tracked list.
var notifyCollectionChangedEventArgs = e.ConvertToNotifyCollectionChangedEventArgs();
if (notifyCollectionChangedEventArgs != null)
{
TrackedListUtilities.ReplayChanges <TTrackedModel, TTrackedModel>(
notifyCollectionChangedEventArgs,
this.Items,
(sourceModel, targetModel) => sourceModel.Id.Equals(targetModel.Id),
tm => tm);
}
}
}
private void ObservableCollection_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.OldItems != null)
{
MultipleItemsRemovedFromCollection(e.OldItems.Cast <TTrackedModel>());
}
if (e.NewItems != null)
{
MultipleItemsAddedToCollection(e.NewItems.Cast <TTrackedModel>());
}
// Update shared data service.
TrackedListUtilities.ReplayChanges <TTrackedModel, TTrackedModel>(
e,
trackedList,
(sourceModel, targetModel) => sourceModel.Id.Equals(targetModel.Id),
vm => vm);
OnCollectionChanged(e);
this.CollectionChanged?.Invoke();
}