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I am using the DataGrid control from Windows Community Toolkit for UWP, but I can't find a solution to dynamically hide or show columns.

Runtime error: Failed to assign to property 'Microsoft.Toolkit.Uwp.Ui.Controls.DataGridColumn.Visibility'

<controls:DataGrid x:Name="TradeGrid">
  <controls:DataGridTextColumn
    x:Uid="DataColumnPositionContract"
    Width="SizeToCells"
    Binding="{Binding Path=TradePosition.Contract.Name}"
    Tag="Contract"
    Visibility="{Binding ElementName=TradeGrid, Path=DataContext.IsContractVisible, Converter={StaticResource BoolToVisConv}}" />
</controls:DataGrid>

The view model structure looks like:

PageViewModel (bound to page)

  • List of items (itemsource of DataGrid)
  • Column visibility properties

ItemViewModel (DataContext of a column)

  • Item properties

The converter is the converter provided by the toolkit. The boolean property to bind is not part of the DataContext of the column (ItemViewModel). I need to access the parent view model (PageViewModel) to get the property.

Can anyone give me a hint on how to bind to the Visibility property of a DataGridColumn?

I am open for other solutions if the binding is not possible this way in UWP.

Thanks!

xmashallax
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1 Answers1

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Firstly, I cannot reproduce the Runtime error based on the code provided by you.

Secondly, the Visibility property of DataGridTextColumn is not a dependency property from the source code, so the binding will not work.

So, you could try to set the value of Visibility property to Visibility.Collapsed or Visibility.Visible directly when you know the target columns to hide or show.

Update:

If you want to set the Visibility property directly, you need to know the index(such as the “0”) of the target column and write the code in a method in code-behind such as a Click event handler on a button, like this:

dataGrid1.Columns.ElementAt(0).Visibility = Visibility.Visible;

You can use {x:Bind} extension instead of {Binding} extension to show or hide columns in a DataGrid, and the binding source class need to implement System.ComponentModel.InotifyPropertyChanged, like this

<controls:DataGridTextColumn 
            ……    Visibility="{x:Bind SourceClass.Visible,Mode=OneWay}"  />

You can change the value of SourceClass.Visible to show or hide a column at runtime.

YanGu
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  • How can I set the `Visibility` property directly? In a method in code-behind? Is there no way to use a binding to show/hide columns in a DataGrid on demand at runtime? – xmashallax Oct 27 '20 at 14:45
  • I update the previous answer, you could check if it can meet your requirements. – YanGu Oct 28 '20 at 07:43
  • I went with the code-behind solution as my view models would need some refactoring before I could use `{x:Bind}`. It's working, so I could reach my goal! – xmashallax Oct 28 '20 at 14:36