Unable to cast type isse in silverlight

Question

Once I click on the button i am getting this error.

This is my code

<sdk:DataGrid MinHeight="100" x:Name="dgCounty" AutoGenerateColumns="False"
 VerticalAlignment="Top"  IsReadOnly="True"  Margin="5,5,5,0"
 RowDetailsVisibilityChanged="dgCounty_RowDetailsVisibilityChanged"
 RowDetailsVisibilityMode="VisibleWhenSelected">
 <sdk:DataGrid.Columns>
   <data:DataGridTemplateColumn.CellTemplate>
     <DataTemplate>
        <Button Content="+" Click="Button_Click"></Button>
     </DataTemplate>
   </data:DataGridTemplateColumn.CellTemplate>
   <sdk:DataGridTextColumn Header="Countryname" Width="100"
     Binding="{Binding Region Name}" CanUserReorder="False"/>
     <sdk:DataGridTextColumn Header="Populution" Width="80"
       Binding="{Binding Number Of People}" CanUserReorder="False"/>
     </sdk:DataGrid.Columns>
     <sdk:DataGrid.RowDetailsTemplate>
       <DataTemplate>
         <sdk:DataGrid x:Name="dgrdRowDetail" Width="400" AutoGenerateColumns="False"
           HorizontalAlignment="Center" IsReadOnly="True" Grid.Row="1">
           <sdk:DataGrid.Columns>
             <sdk:DataGridTextColumn Header="county" Binding="{Binding CompanyName}" />
             <sdk:DataGridTextColumn Header="Number Of People" Binding="{Binding CompanyID}"/>
           </sdk:DataGrid.Columns>
         </sdk:DataGrid>
       </DataTemplate>
     </sdk:DataGrid.RowDetailsTemplate>
   </sdk:DataGrid>

code:-

private void Button_Click(object sender, RoutedEventArgs e)
        {
            Button btnExpandCollapse = sender as Button;

            var Row = DataGridRow.GetRowContainingElement(sender as FrameworkElement);
            if (Row.DetailsVisibility == Visibility.Collapsed)
            {
                Row.DetailsVisibility = Visibility.Visible;
            }
            else
            {
                Row.DetailsVisibility = Visibility.Collapsed;
            }



            if (btnExpandCollapse.Content.ToString() == "+")
            {
                btnExpandCollapse.Content = "-";
            }
            else if (btnExpandCollapse.Content.ToString() == "-")
            {
                btnExpandCollapse.Content = "+";
            }


        }

 void dtg_RowDetailsVisibilityChanged(object sender, DataGridRowDetailsEventArgs e)
        {

            DataGrid RowDetails = e.DetailsElement as DataGrid

            if(RowDetails.YourDesiciveFlag = true)
            {

            }
             else
              {

            }


        }
}

Working on this issue from past 3 days any idea how to solve this issue. just going mad on this issue. for expand /collpase in data grid in silverlight.

Let me know if you people can provide me any code that can solve my issue.

thanks in advance prince

Answer 1

From the looks of your code, you are trying to do what I've shown here:

http://gallery.expression.microsoft.com/en-us/ToggleRowDetail

Hopefully the code sample (a behavior) can help you. Michael