Problem with TreeView

>>I think the second one would work, but now that you seen more of the code, I do appreciate your thoughts and opinions on how I should solve the problem with the child leaves.

The PartsList class doesn't seem to contain any property that contains other PartsList objects so it is not hierarchical...You need to add a collection property to the PartsList class that returns the child parts of that particular PartsList object. I have already provided you with such an example: https://social.msdn.microsoft.com/Forums/vstudio/en-US/fdebbcf9-6e3d-4be6-b110-728154305d1c/wpf-treeview-get-child-and-parent?forum=wpf. The Discipline class has a Tests property that returns a collection of Test objects. In this case you set the ItemsSource property of the HierarchicalDataTemplate to "Tests". You need to add a corresponding collection property to your class if you intend to display hierarchical items in a TreeView:

public class PartsList
{
        public long PartsListID { get; set;}
        public long? PartID { get; set;}
        public long? VendorID { get; set;}
        public string VendorName { get; set;}
        public string VendorPartNo { get; set;}
        public string VendorPartNoLink { get; set;}
        public double? Price { get; set;}
        public string Alternative { get; set;}
        public string AlternativeLink1 { get; set;}
        public string AlternativeLink2 { get; set;}
        public string AlternativeLink3 { get; set;}
        public string Description { get; set;}
        public virtual StockControl StockControl { get; set;} public ICollection<PartsList> Children {get;set;}
 public bool IsParent {get { return this.Children != null && this.Children.Any(); }}
}

Then you set the ItemsSource of the HierarchicalDataTemplate to the Children collection, put all TextBlocks in the same HierarchicalDataTemplate and use a DataTrigger that binds to some property (IsParent) of a PartsList that determines whether it is a leaf or parent node and then change the Visibility property of the TextBlocks to be shown/hidden as I explained in my previous reply.

<HierarchicalDataTemplate DataType="{x:Type local:ParentPart}" ItemsSource="{Binding Children}">
                    ...</HierarchicalDataTemplate>

You won't be able to display hierarchical data unless the PartsList class has any collection property.

And just taking some auto generated Entity Framework class and plug it in into a solution as-is is rarely going to work in a real time scenario. You will have to modify or wrap the POCO class to make it adopt to your WPF requirements. In this case you have to add a collection property to it and populate it with the child objects for each PartsList.

Hope that helps.

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