WPF TableOfContents now expanded by default (100.7.1)

Question

In previous versions of the TableOfContents control the treeview was collapsed by default. Now in 100.7.1 it is expanded by default. We have a large number of layers and this is not acceptable to the users. Current default: I tried to see if I could close them when the TableOfContents is loaded by setting IsExpanded on the item to false, but this did not take foreach (var item in TableOfContents.ItemsSource) { if ( item is TocItem tocItem ) { tocItem.IsExpanded = false; } }‍‍‍‍‍‍‍ How can I get these to be collapsed when the TableOfContents initially Morten Nielsen‌ Thanks -Joe

JoeHershman · Accepted Answer

I did find a solution that works by setting the IsExpanded when the item is added to the collection. The following was added in the views code behind constructor var collection = TableOfContents.ItemsSource as INotifyCollectionChanged; if ( collection == null ) return; collection.CollectionChanged += (sender, args) => { if ( args.NewItems == null ) return; foreach (var item in args.NewItems) { if ( item is TocItem tocItem ) { tocItem.IsExpanded = false; } } };‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍