File list (Check if you may need any files):
TreeViewWithViewModelDemo
.........................\BusinessLib
.........................\...........\BusinessLib.csproj
.........................\...........\DataAccess
.........................\...........\..........\Database.cs
.........................\...........\DataModel
.........................\...........\.........\City.cs
.........................\...........\.........\Person.cs
.........................\...........\.........\Region.cs
.........................\...........\.........\State.cs
.........................\...........\Properties
.........................\...........\..........\AssemblyInfo.cs
.........................\TreeViewWithViewModelDemo
.........................\.........................\App.xaml
.........................\.........................\App.xaml.cs
.........................\.........................\DemoWindow.xaml
.........................\.........................\DemoWindow.xaml.cs
.........................\.........................\LoadOnDemand
.........................\.........................\............\Images
.........................\.........................\............\......\City.png
.........................\.........................\............\......\Region.png
.........................\.........................\............\......\State.png
.........................\.........................\............\LoadOnDemandDemoControl.xaml
.........................\.........................\............\LoadOnDemandDemoControl.xaml.cs
.........................\.........................\............\ViewModel
.........................\.........................\............\.........\CityViewModel.cs
.........................\.........................\............\.........\CountryViewModel.cs
.........................\.........................\............\.........\RegionViewModel.cs
.........................\.........................\............\.........\StateViewModel.cs
.........................\.........................\............\.........\TreeViewItemViewModel.cs
.........................\.........................\Properties
.........................\.........................\..........\AssemblyInfo.cs
.........................\.........................\..........\Resources.Designer.cs
.........................\.........................\..........\Resources.resx
.........................\.........................\..........\Settings.Designer.cs
.........................\.........................\..........\Settings.settings
.........................\.........................\TextSearch
.........................\.........................\..........\TextSearchDemoControl.xaml
.........................\.........................\..........\TextSearchDemoControl.xaml.cs
.........................\.........................\..........\ViewModel
.........................\.........................\..........\.........\FamilyTreeViewModel.cs
.........................\.........................\..........\.........\PersonViewModel.cs
.........................\.........................\TreeViewWithViewModelDemo.csproj
.........................\TreeViewWithViewModelDemo.sln