DataGridCheckBoxColumn immediate binding

Question

I'm using the WPF Toolkit Datagrid and have one column which is a DataGridCheckBoxColumn bound to a bool property on my ViewModel.

My problem is that I wan't the property to get it's value updated immediately when the user checks or unchecks the checkbox.

Now you have to navigate away from the cell in order to have the property updated. It's a checkbox. It can't be in the middle of editing like a textbox can.

Solution 1

You have to set the UpdateSourceTrigger property of the Binding to PropertyChanged. The default is LostFocus.

Solution 2

The solution is to NOT use the DataGridCheckBoxColumn for this. Instead use

<dg:DataGridTemplateColumn Width="20" Header="" SortMemberPath="IsSelected">
   <dg:DataGridTemplateColumn.CellTemplate>
      <DataTemplate>
         <CheckBox  IsChecked="{Binding Path=IsSelected}" />
       </DataTemplate>
   </dg:DataGridTemplateColumn.CellTemplate>
 </dg:DataGridTemplateColumn>

which defaults to having its UpdateSourcerigger to PropertyChanged...

DataGridCheckBoxColumn has it's UpdateSourceTrigger set to Explicit and it cannot be changed. Read more here: http://blogs.msdn.com/vinsibal/archive/2009/04/07/5-random-gotchas-with-the-wpf-datagrid.aspx

Comments

[greenoldman]

No, it does not default to it. You have to set it manually, i.e. "UpdateSourceTrigger=PropertyChanged". Otherwise you will make changes only visually (VS2010). Anyway, BIG THANK YOU for the help.

[Will Dean]

This worked for me (WPF4) too - perhaps this was something that changed for .NET4

[aruno]

note: you need to do UpdateSourceTrigger even for a textbox inside a DataGrid. probably want PropertyChanged=LostFocus in this case (even though this is the default)

[Richard]

Not for me it doesn't. (WPF4)

[Aducci]

I had to do this when using Silverlight 5