/// <summary>
/// This delagate is called when the view model is changed.
/// </summary>
/// <param name="pObject">The event sender.</param>
/// <param name="pEventArgs">The event arguments.</param>
private static void OnViewModelChanged(DependencyObject pObject, DependencyPropertyChangedEventArgs pEventArgs)
{
TreeListView lTreeListView = pObject as TreeListView;
if (lTreeListView != null && lTreeListView.InnerListView != null)
{
// Unloading the view model from the inner list.
lTreeListView.InnerListView.ViewModel = null;
// Invalidating the old view model.
IRootHierarchicalItemViewModel lOldViewModel = pEventArgs.OldValue as IRootHierarchicalItemViewModel;
if (lOldViewModel != null)
{
lOldViewModel.PropertyChanged -= lTreeListView.OnRootViewModelPropertyChanged;
lOldViewModel.ItemViewModelModified -= lTreeListView.OnItemViewModelModified;
}
// Loading the new view model.
lTreeListView.LoadViewModel();
// Notifying the user.
if (lTreeListView.ViewModelChanged != null)
{
lTreeListView.ViewModelChanged(lTreeListView, pEventArgs);
}
}
}
/// <summary>
/// This delagate is called when the view model is changed.
/// </summary>
/// <param name="pSender">The event sender.</param>
/// <param name="pEventArgs">The event arguments.</param>
private static void OnViewModelChanged(DependencyObject pSender, DependencyPropertyChangedEventArgs pEventArgs)
{
ExtendedListView lExtendedListView = pSender as ExtendedListView;
if (lExtendedListView != null)
{
// Unloading the old view model.
IRootHierarchicalItemViewModel lOldViewModel = pEventArgs.OldValue as IRootHierarchicalItemViewModel;
if (lOldViewModel != null)
{
// Unregistering from items modification events.
lOldViewModel.ItemViewModelsAdded -= lExtendedListView.OnItemViewModelsAdded;
lOldViewModel.ItemViewModelsRemoved -= lExtendedListView.OnItemViewModelsRemoved;
lOldViewModel.ItemViewModelMoved -= lExtendedListView.OnItemViewModelMoved;
// Initializing the view model.
lExtendedListView.DropChildrenItems(lOldViewModel, false);
}
// Loading the new view model.
IRootHierarchicalItemViewModel lNewViewModel = pEventArgs.NewValue as IRootHierarchicalItemViewModel;
if (lNewViewModel != null)
{
// Registering on items modification events.
lNewViewModel.ItemViewModelsAdded += lExtendedListView.OnItemViewModelsAdded;
lNewViewModel.ItemViewModelsRemoved += lExtendedListView.OnItemViewModelsRemoved;
lNewViewModel.ItemViewModelMoved += lExtendedListView.OnItemViewModelMoved;
// Loading the first level items.
lExtendedListView.LoadsChildrenItems(lNewViewModel);
}
}
}
