Shatranj – Capture Mouse hover to highlight piece thru Triggers

You can define a Property trigger (Since IsMouseOver is a Dependency Property) (fortunately UserControl has a dependency property IsMouseOver…  IsMouseOver is defined in UIElement).

    <UserControl.Resources>

        <Style TargetType="{x:Type Shatranj:BoardSquareView}">

            <Setter Property="Background" Value="{Binding Converter={StaticResource LocationToColorConverter}}" />

            <Style.Triggers>

                <Trigger Property="IsMouseOver" Value="true">

                    <Setter Property="Foreground" Value="Red" />

                    <Setter Property="Background" Value="Black" />

                    <Setter Property="BorderBrush" Value="Red"/>

                    <Setter Property="BorderThickness" Value="2"/>

                </Trigger>

            </Style.Triggers>

        </Style>

        <Shatranj:BoolToVisibilityConverter x:Key="BoolToVisibilityConverter" />

    </UserControl.Resources>

The next step is to capture the Click.  So, we can have a different colours to indicate selection:

A search of UserControl using Object Explorer (in VS2008) quickly reveals there’s no dependency property for mouse clicks.  Since there’s a ContentPresenter in the BoardSquareView usercontrol – which exposes MouseUp/Down as events, it could be captured in code-behind thus:

    <ContentPresenter MouseUp="ContentPresenter_MouseUp">

        private void ContentPresenter_MouseUp(object sender, System.Windows.Input.MouseButtonEventArgs e)

        {

            this.Background = new SolidColorBrush(Colors.DarkBlue);

            this.Foreground = new SolidColorBrush(Colors.LightGreen);

            this.BorderBrush = new SolidColorBrush(Colors.LightGreen);

            this.BorderThickness = new Thickness(2);

            var context = this.DataContext as BoardSquare;

            //context.Select(true, MoveOptions.AllApplicable);

        }

The above code has its upshots even though it’s not done through styling / attached behaviours.  Will see more in the next post.

 

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