Question

I have three linked Entities (Categories->Types->Classes) with one to many relationship.
Is it possible to bind only Categories entity and represent the rest using Navigation properties andHierarchicalDataTemplate ?

I imagine something like this :

<TreeView ItemsSource="{Binding Categories}">

            <TreeView.ItemTemplate>

                <HierarchicalDataTemplate ItemsSource="{Binding Categories}" >
                    <TextBlock Foreground="Red" Text="{Binding Types}" />

                    <HierarchicalDataTemplate.ItemTemplate>
                        <HierarchicalDataTemplate ItemsSource="{Binding Classes}">
                            <TextBlock Text="{Binding TypeName}" />

                            <HierarchicalDataTemplate.ItemTemplate>
                                <DataTemplate >
                                    <TextBlock Text="{Binding ClassName}" />
                                </DataTemplate>
                            </HierarchicalDataTemplate.ItemTemplate>

                        </HierarchicalDataTemplate>

                    </HierarchicalDataTemplate.ItemTemplate>

                </HierarchicalDataTemplate>
            </TreeView.ItemTemplate>

        </TreeView>

Answer 1

I’ve done this recently, in a WPF project, I’ve updated the Types to match your names and Nav Properties.

You might want to consider changing Type/Class to something more specific since they’re used as keywords in the c# language, but I think you get the idea

  <!-- The Root Category Table -->
           <HierarchicalDataTemplateDataType="{x:Type Entities1:Categories}" ItemsSource="{Binding Types}" >
              <StackPanel Orientation="Horizontal">
                 <Image Name="img" Source="{Binding ., Converter={Converters:DataTypeImageConverter}}" />
                 <TextBlock Text="{Binding CategoryName}" FontWeight="Bold" />
              </StackPanel>
           </HierarchicalDataTemplate>
           <!-- Your Type Table -->
           <HierarchicalDataTemplate DataType="{x:Type Entities1:Type}"  ItemsSource="{Binding Classes}" >
              <StackPanel Orientation="Horizontal">
                 <Image Name="img" Source="{Binding ., Converter={Converters:DataTypeImageConverter}}" />
                 <TextBlock  Text="{Binding TypeName}" />
              </StackPanel>
           </HierarchicalDataTemplate>
           <!-- Your Class Table-->
           <DataTemplate DataType="{x:Type Entities1:Class}">
              <StackPanel Orientation="Horizontal">
                 <Image Name="img" Source="{Binding ., Converter={Converters:DataTypeImageConverter}}" />
                 <TextBlock Text="{Binding ClassName}" />
              </StackPanel>
           </DataTemplate>

What this will do is, it will match the datatype in the tree – If it matches Category, it will create the stackpanel, then start another branch, using the navigation collection Types.

For types, it will do the same basic thing – create the panel for that item, then another branch, for it’s navigation collection Class.

If it’s class, it will only create the panel, since it’s a DataTemplate, not a HierarchicalDataTemplate