Data binding to SelectedItem in a WPF Treeview

Question

How can I retrieve the item that is selected in a WPF-treeview? I want to do this in XAML, because I want to bind it.

You might think that it is SelectedItem

Answer 1

This can be accomplished in a 'nicer' way using only binding and the GalaSoft MVVM Light library's EventToCommand. In your VM add a command which will be called when the selected item is changed, and initialize the command to perform whatever action is necessary. In this example I used a RelayCommand and will just set the SelectedCluster property.

public class ViewModel
{
    public ViewModel()
    {
        SelectedClusterChanged = new RelayCommand( c => SelectedCluster = c );
    }

    public RelayCommand SelectedClusterChanged { get; private set; } 

    public Cluster SelectedCluster { get; private set; }
}

Then add the EventToCommand behavior in your xaml. This is really easy using blend.