Question

I found a nice solution on this webiste http://www.thesilvermethod.com/Default.aspx?Id=ModalDialogManagerAsimpleapproachtodealingwithmodaldialogsinMVVM

But had to do some changes to get it integrated into my code. Along the way I get some small problems mostly because there are certain parts of the code I’m not getting completely.

How I did it was to bind the ModalDialogManager to a MainWindow property of the Type IDialogViewModel. I then have a WindowsManager class that handles putting the right instance inside this property. One such is EditDialogViewModel that exposes a EditableViewModel to this DialogManager. I set the EditDialog view as a DataTemplate for this EditDialogViewModel but when I show it the new window only shows a part of it.

Here is the View:

<UserControl.Resources>

    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>

            <ResourceDictionary Source="EditDataTemplates.xaml" />

        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>

</UserControl.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="7*" />
            <RowDefinition Height="2*" />
            <RowDefinition Height="1*" />
        </Grid.RowDefinitions>

        <ContentControl Content="{Binding Path=ViewModel}" />

        <TextBlock Text="{Binding Path=ViewModel.Error}" />

        <UniformGrid Grid.Row="2" Columns="2">

            <Button Command="{Binding SaveCommand}" />

            <Button Command="{Binding CancelCommand}" />

        </UniformGrid>

    </Grid>
</UserControl>

But the new Dialog window only shows the ContentControl bound to the ViewModel property of EditDialogViewModel (it holds the ViewModel being edited).

My guess is it has something to do with this code in the ModelDialogManager:

 void Show()
    {
        if (_window != null) Close();

        Window w = new Window();
        _window = w;
        w.Closing += w_Closing;
        w.Owner = GetParentWindow(this);

        w.DataContext = this.DataContext;
        w.SetBinding(Window.ContentProperty, ""); //This code here does something I don't fully understand

        w.Title = Title;
        w.Icon = Icon;
        w.Height = DialogHeight;
        w.Width = DialogWidth;
        w.ResizeMode = DialogResizeMode;
        w.ShowDialog();
    }

He is applying the binding there but I guess it’s only the first ContentControl that gets bound or something. It’s quite tricky.

Another problem is that the mouse just doesn’t work inside the Modal Dialog. I can tab into the textboxes but not click into them.

Is there a way to fix this or a better method to handle Modal Dialog boxes in WPF?

EDIT

Ok I’m going to admit it. I’m a huge idiot. This was so simple I just couldn’t see it. I had set Height and Width on the UserControl to a fixed value while I was still messing around with it being a Window. So in actuality it was showing the whole thing, there just wasn’t room. I have no idea why the mouse didn’t work at that point but now it works perfectly.

Answer 1

Answering “a better method to handle Modal Dialog boxes in WPF?” there is a new control called Child Window in the WPF Extended Toolkit that addresses your Modal Dialog pains.