Silverlight dataform MVVM command binding on update - silverlight

Question

I'm new to MVVM and Silverlight and I'm just trying to figure out a simple scenario.
I'm using the MVVM Light toolkit and Silverlight 3.0 without Expression Blend.
I have a DataGrid and a DataForm bound to an observable collection in a ViewModel. I would like to bind to my RelayCommand Save() property after I make changes to the data in the DataForm control and have this accomplished without using the code behind for my view.
The DataForm doesn't use the cmd:ButtonBaseExtensions.Command that MVVM Light uses for normal button click command binding, so I'm not sure how to tie the control to my ViewModel.
Any help is appreciated!

Answer 1

I figured it out shortly after posting the question. Go figure.
When using the MVVM Light Toolkit you can bind to events using the EventToCommand feature.
My Xaml looks like this:
<UserControl x:Class="CountyBusinessDirectory.UI.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
xmlns:dataFormToolkit="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data.DataForm.Toolkit"
xmlns:data="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data"
xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight"
xmlns:cmdextras="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras"
DataContext="{Binding BusinessesViewModel, Source={StaticResource Locator}}">
<Grid x:Name="LayoutRoot" ShowGridLines="False">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="2*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<data:DataGrid x:Name="dgAllBusinesses" CanUserSortColumns="True"
IsReadOnly="True" AutoGenerateColumns="True"
ItemsSource="{Binding Businesses}"
Grid.Column="0">
</data:DataGrid>
<ScrollViewer x:Name="svScroll" Grid.Column="1" >
<dataFormToolkit:DataForm x:Name="dfDetails"
ItemsSource="{Binding Businesses}"
AutoGenerateFields="True"
CommitButtonContent="Save"
CommandButtonsVisibility="Edit, Navigation, Commit, Cancel" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="EditEnded">
<cmdextras:EventToCommand Command="{Binding SaveBusiness}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</dataFormToolkit:DataForm>
</ScrollViewer>
</Grid>
And my ViewModel looks like this (using direct silverlight enabled WCF service in ViewModel for quick example, would normally pull this into an interface to decouple):
//using statements ommitted for brevity
namespace MyProject.ViewModels
{
public class BusinessesViewModel : ViewModelBase
{
private PagedCollectionView _businesses;
DALServiceClient _proxy;
public RelayCommand SaveBusiness
{ get; private set; }
public PagedCollectionView Businesses
{
get
{
return _businesses;
}
set
{
if (_businesses != value)
{
_businesses = value;
base.RaisePropertyChanged("Businesses");
}
}
}
public BusinessesViewModel()
{
_proxy = new DALServiceClient(); //Data Access Layer WCF Service
_proxy.GetBusinessesCompleted += new EventHandler<GetBusinessesCompletedEventArgs>(_proxy_GetBusinessesCompleted);
_proxy.GetBusinessesAsync();
SaveBusiness = new RelayCommand(() => SaveBusinessToDB());
}
private void SaveBusinessToDB()
{
Business bus = Businesses.CurrentItem as Business;
_proxy.UpdateBusinessesAsync(bus);
}
void _proxy_GetBusinessesCompleted(object sender, GetBusinessesCompletedEventArgs e)
{
if (e.Result != null)
{
Businesses = new PagedCollectionView(e.Result);
}
}
}
}