ViewModel

Creating a ViewModel

• To create a ViewModel for MyUserControl:
  • Add a new class to the same namespace where your UserControl is located
    • Name it [TheNameOfTheUserControl]ViewModel (in this case: MyUserControlViewModel)
  • Set the base class to ViewModel (from GM.WPF.MVVM)

using GM.WPF.MVVM;

namespace MyWpfApplication
{
    class MyUserControlViewModel : ViewModel
    {
        // ...
    }
}

Using the ViewModel

• In the MyUserControl constructor, set the property ViewModel to an instance of your ViewModel class

public MyUserControl()
{
    InitializeComponent();
    
    var vm = new MyUserControlViewModel();
    ViewModel = vm;
}

You can get the ViewModel later like this:

var vm = (MyUserControlViewModel)ViewModel;

• [optional] In the MyUserControl.xaml file, add this attribute to the opening tag: d:DataContext="{d:DesignInstance Type=local:MyUserControlViewModel, IsDesignTimeCreatable=True}"

If your ViewModel implements IDisposable and is used inside the BaseControl or BaseWindow, it will automatically be disposed when the window closes.