Getting Window from view model

Question

I have created a custom messageBox Window to replace the typical MessageBox.

My custom messageBox (child Window) needs parent window to be passed as an argument. The

Answer 1

How can I get the Window associated to the view model?

You could inject the view model with an interface that the window implements:

public interface IView
{
    double Top { get; }
    double Left { get; }
    double Height { get; }
    double Width { get; }
}

public partial class MainWindow : Window, IView
{
    public MainWindow()
    {
        InitializeComponent();
        DataContext = new ViewModel(this);
    }
}

public class ViewModel
{
    private readonly IView _view;

    public ViewModel(IView view)
    {
        _view = view;
    }

    //...
}

Then the view model knows only about an interface (which maybe should be called something else than IView).

If you want an ugly and non-MVVM friendly shortcut, you could use the Application class:

var win = Application.Current.MainWindow;

A factory class to create everything:

public MainWindow WindowFactory()
{
    MainWindow mainWindow = new MainWindow();
    ViewModel viewModel = new ViewModel();
    mainWindow.DataContext = viewModel;

    return mainWindow;
}