Question

I’m completely new to WPF.

I’m making a simple application in the MVVM pattern.

I have a viewmodel with a model referenced in it. The model contains some netelements I want to put in a combobox.

Here is the relevant part of the viewmodel:

public class MainWindowVM : ViewModelBase
{
    private Model _model = null;

    public Model Model
    {
        get
        {
            return _model;
        }
    }

    #region ActiveElement

    private NetElement _activeElement = null;

    public NetElement ActiveElement
    {
        get
        {
            return _activeElement;
        }
        set
        {
            if (_activeElement != value)
            {
                _activeElement = value;
                RaisePropertyChanged("ActiveElement");
                if (ActiveElementChanged != null)
                    ActiveElementChanged(this, EventArgs.Empty);
            }
        }
    }
}

I would like to be able to select a NetElement in a combobox and set the ActiveElement to it.

here is the relevant part of my current XAML:

<ItemsControl Background="White" IsTabStop="True" ItemsSource="{Binding Path=Model.RootNet.Elements}">
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <TextBlock Margin="2,6">
            <Hyperlink Command="{Binding Path=I'm not able to figure out what to write here}">
              <TextBlock Text="{Binding Path=Name}" />
            </Hyperlink>
          </TextBlock>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

This is not a combobox but a list of TextBlocks, but you can see where it is going.

How can I set the ActiveElement from the view?

Answer 1

Create a binding for the SelectedItem property of the ComboBox to your ActiveElement property:

 <ComboBox SelectedItem="{Binding Path=ActiveElement}" ... />

then set the DataContext property of the view to your view model.