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.netwpftriggersdatatriggerstackpanel

Defining DataTrigger for StackPanel


How do I define a DataTrigger for a StackPanel? It does have a Trigger property, but defining a trigger here gives the following error on Initialize when starting the application:

Failed object initialization (ISupportInitialize.EndInit). Triggers collection members must be of type EventTrigger. ....

This is given from the following simple DataTrigger:

<StackPanel x:Name="PersonPanel" DataContext="{Binding CurrentPerson}">
    <TextBlock Text="{Binding Id}" />
    <TextBlock Text="{Binding Name}" />
    <StackPanel.Triggers>
        <DataTrigger Binding="{Binding Id}" Value="1">
            <Setter TargetName="PersonPanel" Property="StackPanel.Background" Value="Green" />
        </DataTrigger>                
    </StackPanel.Triggers>
</StackPanel>

This is my first Trigger ever, so what do I do wrong? Should I define the Trigger elsewhere?


Solution

  • Try something like this

       <Window.Resources>
            <Style x:Key="spStyle" TargetType="StackPanel">
                <Setter Property="StackPanel.Background" Value="Red" />
                <Style.Triggers>
                    <DataTrigger Binding="{Binding Id}" Value="1">
                        <Setter Property="StackPanel.Background" Value="Green" />
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </Window.Resources>
        <StackPanel x:Name="PersonPanel" Style="{StaticResource spStyle}" DataContext="{Binding CurrentPerson}">
            <TextBlock Text="{Binding Id}" />
            <TextBlock Text="{Binding Name}" />
        </StackPanel>