Linq with Xceed's WPF Grid - Part II

In my first post I showed a handy binding class that wraps around your linq data tables, now I'm going to show some handy changes to Xceed's data grid, to complete the linq binding.

My main problem with the data grid, is there isn't any good place to commit a transaction after editing a row.

To fix this, we can provide our own DataRow class which handles the SubmitChanges() when a row is dirty.

Update: Modified code to use IsDirty flag. Note that IsDirty is reset to false in base.EndEdit().

 class LinqRow : DataRow
 {
   public override void EndEdit()
   {
     if (IsDirty == true)
       DataSource.Context.SubmitChanges();
   
     base.EndEdit();
   }
 }
  

To make the DataGridControl aware of our new DataRow class, we need to derive and override the GetContainerForItemOverride() method.

 class LinqGrid : DataGridControl
 {
   protected override DependencyObject 
       GetContainerForItemOverride()
   {
     return new LinqRow();
   }
  
   protected override void OnInitialized(EventArgs e)
   {
     base.OnInitialized(e);
  
     if (View == null)
     {
       View = new TableView();
       AdjustHeadersFooters();
     }
   }
  
   private void AdjustHeadersFooters()
   {
     // Show / hide the element base
     View.FixedHeaders.Clear();
     View.Headers.Clear();
  
     // Add a ColumnManagerRow
     DataTemplate columnTemplate = new DataTemplate();
     columnTemplate.VisualTree = 
       new FrameworkElementFactory(typeof(ColumnManagerRow));
     View.FixedHeaders.Add(columnTemplate);
  
     // Add the insertion row
     DataTemplate insertTemplate = new DataTemplate();
     insertTemplate.VisualTree = 
       new FrameworkElementFactory(typeof(InsertionRow));
     View.FixedHeaders.Add(insertTemplate);
   }
 }
  

Insertion Row

You may have noticed the AdjustHeadersFooters call in the class above, this code removes the GroupBy control and adds in the Insertion row by default. The GroupBy control is cool, but I rarely use it.

Putting it together

Instead of using the DataGridControl in your xaml file, simply use the LinqGrid.

In my next few posts I'll discuss hooking up the delete, sorting and filtering, and how to use the linq queries instead of the whole table.