TreeViewItem.Expanded
问题 Im using the latest version of mvvm light toolkit, however i'm not clear how I can use EventToCommand for the event TreeViewItem.Expanded. THis dosent work... what am I doing wrong? <TreeView Grid.Column="0" Grid.Row="0" ItemsSource="{Binding Path= MonitoredDatabases}"> <TreeView.ItemTemplate> <HierarchicalDataTemplate ItemsSource="{Binding Queues}"> <StackPanel Orientation="Horizontal"> <TextBlock Text="{Binding ServerName}" /> <TextBlock Text="\" /> <TextBlock Text="{Binding DatabaseName}"