Muliple items keep selecting even with SelectionMode="Single"

[Ken]

Hi there, 

I am using a RadGridView, here is the XAML

<telerik:RadGridView Grid.Row="1"
                            Grid.ColumnSpan="3"
                            SelectionMode="Single"
                            IsReadOnly="True"
                            Name="radGridView1"
                            ItemsSource="{Binding Path=ModelCodeList}"
                            SelectedItem="{Binding Path=SelectedModel, Mode=TwoWay}"
                            AutoGenerateColumns="False"  >
           <telerik:RadGridView.Columns>
               <telerik:GridViewDataColumn DataMemberBinding="{Binding Code}" Header="Model"/>
               <telerik:GridViewDataColumn DataMemberBinding="{Binding ID}" Header="ID"/>
               <telerik:GridViewDataColumn DataMemberBinding="{Binding OemName}" Header="OEM Name"/>
               <telerik:GridViewDataColumn DataMemberBinding="{Binding ModalityCode}" Header="Modality Code"/>
               <telerik:GridViewDataColumn DataMemberBinding="{Binding Active}" Header="Model Active"/>
           </telerik:RadGridView.Columns>
       </telerik:RadGridView>

As you can see I am binding the selected item, I followed the example from the code download in this (http://www.telerik.com/community/forums/wpf/gridview/select-a-row-from-viewmodel.aspx) post. I works the first time no problem... I put a breakpoint in my view model and I can see my SelectedModel getting set. The problem is that I can't unselect the first item and have it set the second item. At this point I am stuck - here is the pertinent code from the view model.

public Model SelectedModel
   {
     get { return selectedModel; }
     set
     {
       if (selectedModel != value)
       {
         selectedModel = value;
       }
       RaisePropertyChanged(() => this.SelectedModel);
       AddSelectedModelCommand.RaiseCanExecuteChanged();
     }
   }

What is does is keeps highlighting rows - even though I have SelectionMode="sinlge" - Uhm? Any suggestions? I attached a screen capture to show what I mean - see all the highlighted rows?

Thanks!

** Also - The only difference I can see between my project and the sample is that we are "Target Framework:" is set to ".NET Framework 4" and your project is being built as ".NET Framework 4 Client Profile"

[Milan]

Hi Ken,

Do you data items override GetHashCode and Equals methods by any chance ? If that is the case, problems like the one that you have mentioned can occur if several items have the same hash code. Currently the grid expects that hash codes are unique.

Kind regards,
Milan
the Telerik team

[Ken]

Yeah - it does...

public override bool Equals(object obj)
  {
    bool match = false;

    if (obj.GetType() == typeof(Model))
    {
      Model m = (Model)obj;

      match = Active != m.Active
        || Code != m.Code
        || Description != m.Description
        || ModalityId != m.ModalityId
        || OemId != m.OemId
        || ParentID != m.ParentID;
    }

    return match;
  }

Is there something we could change in the Equals method that would fix it?

Thanks

[Milan]

Hi Ken,

You could try changing the Equals to :

public override bool Equals(object obj)
{
    return ReferenceEquals(this, obj);
}

Hope this helps.

Regards,
Milan
the Telerik team