I have a Silverlight DataGrid
, a DataPager
and a PagedCollectionView
.
After the PagedCollection view is bound to the DataGrid
, the first row of the DataGrid
is selected.
This behaviour does not happen, if i am using an ObservableCollection
. But due to the DataPager
, I need to use the PagedCollectionView
.
I am using Silverlight 5 RC, and the SL 4 Toolkit.
Example of Usage:
<sdk:DataGrid x:Name="gridSomeItems" ItemsSource="{Binding SomeItems, Mode=TwoWay}" SelectedItem="{Binding SelectedItem, Mode=TwoWay}" CanUserSortColumns="True">
<sdk:DataGrid.Columns>
<sdk:DataGridTextColumn Header="Column1" Width="*" Binding="{Binding Column1}" />
</sdk:DataGrid.Columns>
</sdk:DataGrid>
<sdk:DataPager Source="{Binding Path=ItemsSource, ElementName=gridSomeItems}"/>
public class SomeViewModel : ViewModelBase
{
public SomeViewModel(IDataAccess dataAccess)
{
_dataAccess = dataAccess;
_dataAccess.GetSomeItemsCompleted += GetSomeItemsCompleted;
_dataAccess.GetSomeItems();
}
public PagedCollectionView SomeItems { get; set; }
public SomeItem SelectedItem { get; set; }
private void GetSomeItemsCompleted(GetSomeItemsCompletedEventArgs e)
{
SomeItems = new PagedCollectionView(e.Result.SomeItems);
RaisePropertyChanged("SomeItems");
}
}
The best workaround is to set a _isLoading
flag. The following code would be the correct code for the ViewModel:
public class SomeViewModel : ViewModelBase
{
private bool _isLoading;
public SomeViewModel(IDataAccess dataAccess)
{
_dataAccess = dataAccess;
_dataAccess.GetSomeItemsCompleted += GetSomeItemsCompleted;
_isLoading = true;
_dataAccess.GetSomeItems();
}
public PagedCollectionView SomeItems { get; set; }
public SomeItem SelectedItem { get; set; }
private void GetSomeItemsCompleted(GetSomeItemsCompletedEventArgs e)
{
SomeItems = new PagedCollectionView(e.Result.SomeItems);
SomeItems.CurrentChanged += CurrentItemChanged;
RaisePropertyChanged("SomeItems");
SomeItems.MoveCurrentTo(null);
_isLoading = false;
}
private void CurrentItemChanged(object sender, System.EventArgs e)
{
if (!_isLoading)
{
SelectedItem = SomeItems.CurrentItem as SomeItem;
// Do something more...
}
}
}
Please have a look at the row SomeItems.MoveCurrentTo(null);
- This command really sets the CurrentItem of the PagedCollectionView to null (not selected).
It is still a workaround... Would be great if anybody came up with a better solution.