Hello,
when I bind the TaskSource of the RadGanttView (WPF) to a CompositeCollection I get the Exception "Object of Type System.Windows.Data.CollectionContainer cannot be converted to Type IGanttTask". With the RadTreeView it works. All Items in the Collections implements IGanttTask.
<CompositeCollection x:Key="ProjectChildCollection"><br> <CollectionContainer Collection="{Binding DataContext.SelectedProject.ProjectActions, Source={x:Reference control}}" /><br> <CollectionContainer Collection="{Binding DataContext.SelectedProject.Tasks, Source={x:Reference control}}" /><br> <CollectionContainer Collection="{Binding DataContext.SelectedProject.ResourceBookings, Source={x:Reference control}}" /><br> </CompositeCollection>
TasksSource="{Binding Source={StaticResource ProjectChildCollection}}"