Question

I am working with Wpf. I am using TabControl, In some specific condition TabItem’s Header contains ‘*’ symbol. I need to write a trigger so that whenever there is any such content in the Header, TabItem’s Background changes. I am not able to find a way to do this in xaml. Any help plz.

Answer 1

If I understand your question correctly, I think you’re having the same fundamental problem as the person who asked this question: WPF Trigger when property value is greater than a certain amount which unfortunately just links to another forum post: http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/a8ad8c14-95aa-4ed4-b806-d0ae874a8d26/ but I will summarize it here:

If you use a DataTrigger, instead of a regular trigger, and bind to the Header Text you can run the value through an IValueConverter, which will let you convert your string into a boolean True/False value based on whether it has an asterisk or not.

<TabItem Header="TabItem">
    <TabItem.Style>
        <Style TargetType="TabItem">
            <Style.Triggers>
                <DataTrigger Binding="{Binding Path=Header, RelativeSource={RelativeSource Self}, Converter={StaticResource HasAsteriskConverter}}" Value="True">
                    <Setter Property="Foreground" Value="Blue" />
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </TabItem.Style>
<Grid />
</TabItem>

Note that my example sets the foreground, because the tab item style seems to override the background value and this still answers the original question.