Question: Sorting and filtering a templated column

[VisualAlf]

@w-ahmad : Thanks for your time and labour on TableView.

I tried the version of Feb 07, 2025 (52a0ef4) and feel a bit lost at the moment about the usage of IColumnFilterHandler ( as of #98)

Could you please provide a simple example:

• assume a templated column using a TextBlock in the datatemplate (bound to some item.prop).
  something like:

                    <TableViewTemplateColumn Header="Template" Width="100" CanSort="True" CanFilter="True">
                        <TableViewTemplateColumn.CellTemplate>
                            <DataTemplate x:DataType="TestItem" >
                                <TextBlock Text="{x:Bind Name}" />
                            </DataTemplate>
                        <TableViewTemplateColumn.CellTemplate>
                    <TableViewTemplateColumn>

• how can we sort this column ?
• how can we filter this column ?

[w-ahmad]

https://github.com/w-ahmad/WinUI.TableView.SampleApp

@VisualAlf try this sample app, it has custom filter implementation.

[VisualAlf]

@w-ahmad nice and useful app! Thanks.

My question was a followup of #55, where I mentioned my 'overdue-problem', which simply describes a task as: if a certain date in a cell is overdue, draw it in Red.

For that I used to have a TableViewTemplateColumn encapsulating a TextBlock. Which worked, except that Column is not sortable/filterable by default.

Looking at your example, that's possible now. But honestly that's just a lot of code for the simple task at hand.

If we could have a simple Event on a Bound Column that fires after generating an Element, delivering

• the generated Element (so we can manipulate it's attributes)
• the item (e.g. the current row content) so we can base the manipulation on the context

that would reduce the code to 1 attribute on the TableViewColumn and perhaps 3 lines of code behind.

Example:

<Tableview   ... >
   ...
   <TableViewTextColumn 
      x:Name="specialCol"
      ElementGenerated="specialCol_ElementGenerated"             <--- the eventhandler
      ...
   >
</TableView>

Code-behind:

private void specialCol_ElementGenerated(object sender, ElementCreatedEventArgs e)
{
   if (sender is not TableViewTextColumn col || e.Element is not TextBlock tb || e.DataItem is not object item) return;
   if (item.ItemState == TestState.finished) tb.Foreground = new SolidColorBrush(Colors.Magenta);
}

'sender' is the generating column, which gives us access to Binding et. al.

What do you think?

[w-ahmad]

@VisualAlf I would consider adding events on generate element and on generate editing element at some point. but for now, did you try setting ElementStyle to add conditional foreground? The second option to try is, creating custom column type and override generate element method!