WPF TreeView binding shows only top hierachy

Question

I want to have a two level TreeView in WPF, but it doesn't show the second level.

My first class ist

 public class MyClass : BaseViewModel
{
    #region Fields

    public ObservableCollection<MySubClass> SubClassCollection
    {
        get;
        private set;
    }

    #endregion Fields

    #region Propertys

    public string Name
    {
        get
        {
            return Model.Name;
        }
    }

    #endregion Propertys
}

And then i got my MySubClass

public class MySubClass : BaseViewModel
{
    #region Propertys


    public string Name
    {
        get
        {
            return Model.Name;
        }
    }

    public int Number
    {
        get
        {
            return Model.Number;
        }
    }
    #endregion Propertys

}

And my XAML looks like this:

<TreeView ItemsSource="{Binding Path=MyClassCollection, Mode=OneWay}">
    <TreeView.Resources>
        <HierarchicalDataTemplate DataType="{x:Type vm:MyClass}">
            <Grid>
                <TextBlock Text="{Binding Name}" Foreground="{DynamicResource AccentColorBrush}"  />
            </Grid>
        </HierarchicalDataTemplate>
        <DataTemplate DataType="{x:Type vm:MySubClass}">
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="19"></ColumnDefinition>
                    <ColumnDefinition Width="*" />
                </Grid.ColumnDefinitions>
                <TextBlock Text="{Binding Number}" 
                           HorizontalAlignment="Left"
                           />
                <StackPanel Orientation="Horizontal"
                            Grid.Column="1"
                            HorizontalAlignment="Left"
                            >
                    <TextBlock Text=" (" 
                               Foreground="{DynamicResource AccentColorBrush}"  
                               />
                    <TextBlock Text="{Binding Name}" 
                               Foreground="{DynamicResource AccentColorBrush}"  
                               />
                    <TextBlock Text=")" 
                               Foreground="{DynamicResource AccentColorBrush}"  
                               />
                </StackPanel>
            </Grid>
        </DataTemplate>
    </TreeView.Resources>
</TreeView>

But it shows me only a List of MyClass without the relative MySubClass.

What am I doing wrong?

Answer 1

HierarchicalDataTemplate for MyClass is missing ItemsSource binding which provide data for nested levels

<HierarchicalDataTemplate DataType="{x:Type vm:MyClass}" 
                          ItemsSource="{Binding Path=SubClassCollection}">

---

also 3 TextBlocks are redundant

<TextBlock Text=" (" 
           Foreground="{DynamicResource AccentColorBrush}"/>  
<TextBlock Text="{Binding Name}" 
           Foreground="{DynamicResource AccentColorBrush}"/>  
<TextBlock Text=")" 
           Foreground="{DynamicResource AccentColorBrush}"/>  

1 TextBlock with a StringFormat parameter will do

<TextBlock Text="{Binding Name, StringFormat=' (\{0\})'}" 
           Foreground="{DynamicResource AccentColorBrush}"  />

that probably makes StackPanel redundant as well