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c#wpfxamlbindingmaterial-design-in-xaml

Why Color Binding doesn't work for HorizontalGridLinesBrush in DataGrid in WPF

I'm using C# WPF and MaterialDesign Theme, I bound the Background of the VerticalGridLinesBrush property of DataGrid to a Background of Button : enter image description here

NOTE ↑: This works when I use Binding just like this, Not when I want to bind opacity along with it

.

What I need: the Color Binding works as well, but I want to bind the Opacity property of VerticalGridLinesBrush to the Opacity property of that button enter image description here

The Problem

so I tried this in XAML :

         <DataGrid.HorizontalGridLinesBrush>
            <SolidColorBrush Color="Red" Opacity="0.5"/>
        </DataGrid.HorizontalGridLinesBrush>

and it works well: enter image description here

But when I try to use Binding it doesn't work:

        <DataGrid.HorizontalGridLinesBrush>
            <SolidColorBrush Color="{Binding ElementName=GENERAL_RANG,Path=Background}" Opacity="{Binding ElementName=GENERAL_RANG,Path=Opacity}"/>
        </DataGrid.HorizontalGridLinesBrush>

enter image description here

Full XAML:

         <DataGrid x:Name="tASKSDataGrid" 
              EnableRowVirtualization="True"
              VirtualizingPanel.IsVirtualizing="True"
              VirtualizingPanel.VirtualizationMode="Recycling"
              ScrollViewer.CanContentScroll="False"
              SelectionMode="Single"
                           
              FlowDirection="RightToLeft" AutoGenerateColumns="False"  Margin="26,66,230,88" CanUserDeleteRows="False" BorderThickness="1" >
        
        <!--<DataGrid.HorizontalGridLinesBrush>
            <SolidColorBrush Color="Red" Opacity="0.1"/>
        </DataGrid.HorizontalGridLinesBrush>-->
        
        <!--↓-->

        <DataGrid.HorizontalGridLinesBrush>
            <SolidColorBrush Color="{Binding ElementName=MY_BUTTON,Path=Background}" Opacity="{Binding ElementName=GENERAL_RANG,Path=Opacity}"/>
        </DataGrid.HorizontalGridLinesBrush>


        <DataGrid.Columns>
                 <DataGridTextColumn x:Name="IDNUM" Binding="{Binding IDNUM, UpdateSourceTrigger=LostFocus}"  Header="Number" IsReadOnly="True"  MinWidth="50" Width="auto" />
            <DataGridTextColumn x:Name="gRColumn" Binding="{Binding GR, UpdateSourceTrigger=LostFocus}" Visibility="Visible" Header="Personel"  Width="auto" />

          
        </DataGrid.Columns>
    </DataGrid>
    
    <Button x:Name="MY_BUTTON" Visibility="Collapsed" Margin="95,56,0,0"  Width="1"/>

I even removed Opacity Binding but it still does not work!

What should I do?

Solution

  • The type of Background property of Control is Brush. There are a variety of Brushes and SolidColorBrush is one of them. If you are sure that current value of Background is a SolidColorBrush, you can refer its Color property in binding.

    <SolidColorBrush Color="{Binding ElementName=MY_BUTTON,Path=Background.Color}" Opacity="{Binding ElementName=GENERAL_RANG,Path=Opacity}"/>

    However, keep in mind that the value of Background does not necessarily has Color property and this binding won't work depending on its type.