<TreeView.ItemTemplate>
            <HierarchicalDataTemplate ItemsSource="{Binding ElementName=ParentControl, Path=DataContext.ConfigurationGroups}">

                <TextBlock Text="{Binding}"/>

                <!--ConfigurationGroups template-->
                <HierarchicalDataTemplate.ItemTemplate>
                    <HierarchicalDataTemplate ItemsSource="{Binding Configurations}">
                        <HierarchicalDataTemplate.ItemContainerStyle>


                        </HierarchicalDataTemplate.ItemContainerStyle>
                        <TextBlock Text="{Binding Name}"/>

                        <!--Configuration template-->
                        <HierarchicalDataTemplate.ItemTemplate>
                            <DataTemplate>
                                <Grid>
                                    <Grid.InputBindings>
                                        <MouseBinding Gesture="LeftClick"
                                                      Command="{Binding ElementName=ParentControl, Path=DataContext.SelectCurrentTabCommand}"
                                                      CommandParameter="{Binding}"/>
                                    </Grid.InputBindings>
                                    <TextBlock Text="{Binding Name}"/>
                                </Grid>

                            </DataTemplate>
                        </HierarchicalDataTemplate.ItemTemplate>

                    </HierarchicalDataTemplate>
                </HierarchicalDataTemplate.ItemTemplate>

            </HierarchicalDataTemplate>
        </TreeView.ItemTemplate>
    </TreeView>

SelectCurrentTabCommand = new RelayCommand((c) => projectManager.SelectCurrentTab(c as Configuration));