Interaction Triggers in Style in ResourceDictionary WPF

Question

I have a ComboBox which I need to use in several places in my application, so I set most of the properties of that ComboBox in ResourceDictio

Answer 1

As far as I know, Interaction.Triggers can not be applied in Style, respectively and in a ResourceDictionary. But you can do so, to determine the ComboBox as a resource with x:Shared="False" and reference it for ContentControl like this:

When x:Shared="True" by default then one Style is common to all - in this case, the system swears on the duplicate Content. When x:Shared="False" when is created Style for each element whenever it its request. Quote from MSDN:

When set to false, modifies WPF resource-retrieval behavior so that requests for the attributed resource create a new instance for each request instead of sharing the same instance for all requests.

For more information, please see:

MSDN: x:Shared Attribute

Edit: alternative solution

Here, Mr.Vspivak published a solution that allows you easily set the Interaction.Triggers in Style.

Example:

MainWindow.xaml

InteractivityHelper.cs

/// 

///  for InteractivityElements instance
/// Subclassed for forward compatibility, perhaps one day  
/// will not be partially internal
/// 
public class InteractivityTemplate : DataTemplate
{

}

/// 

/// Holder for interactivity entries
/// 
public class InteractivityItems : FrameworkElement
{
    private List _behaviors;
    private List _triggers;

    /// 

    /// Storage for triggers
    /// 
    public List Triggers
    {
        get
        {
            if (_triggers == null)
                _triggers = new List();
            return _triggers;
        }
    }

    /// 

    /// Storage for Behaviors
    /// 
    public List Behaviors
    {
        get
        {
            if (_behaviors == null)
                _behaviors = new List();
            return _behaviors;
        }
    }

    #region Template attached property

    public static InteractivityTemplate GetTemplate(DependencyObject obj)
    {
        return (InteractivityTemplate)obj.GetValue(TemplateProperty);
    }

    public static void SetTemplate(DependencyObject obj, InteractivityTemplate value)
    {
        obj.SetValue(TemplateProperty, value);
    }

    public static readonly DependencyProperty TemplateProperty =
        DependencyProperty.RegisterAttached("Template", 
        typeof(InteractivityTemplate), 
        typeof(InteractivityItems),
        new PropertyMetadata(default(InteractivityTemplate), OnTemplateChanged));

    private static void OnTemplateChanged(
        DependencyObject d, 
        DependencyPropertyChangedEventArgs e)
    {
        InteractivityTemplate dt = (InteractivityTemplate)e.NewValue;
#if(!SILVERLIGHT)
        dt.Seal();
#endif
        InteractivityItems ih = (InteractivityItems)dt.LoadContent();
        BehaviorCollection bc = Interaction.GetBehaviors(d);
        TriggerCollection tc = Interaction.GetTriggers(d);

        foreach (Behavior behavior in ih.Behaviors)
            bc.Add(behavior);

        foreach (TriggerBase trigger in ih.Triggers)
            tc.Add(trigger);
    }

    #endregion
}

FlipOnHover.cs

public class FlipOnHover : Behavior
{
    protected override void OnAttached()
    {
        AssociatedObject.MouseEnter += AssociatedObject_MouseEnter;
        AssociatedObject.MouseLeave += AssociatedObject_MouseLeave;
        Transform t = AssociatedObject.RenderTransform;

        AssociatedObject.RenderTransform = new TransformGroup();
        ((TransformGroup)AssociatedObject.RenderTransform).Children.Add(t);
        ((TransformGroup)AssociatedObject.RenderTransform).Children.Add(new ScaleTransform());
        base.OnAttached();
    }

    void AssociatedObject_MouseLeave(object sender, System.Windows.Input.MouseEventArgs e)
    {
        ((ScaleTransform)((TransformGroup)AssociatedObject.RenderTransform).Children[1]).ScaleY = 1;
    }

    void AssociatedObject_MouseEnter(object sender, System.Windows.Input.MouseEventArgs e)
    {
        ((ScaleTransform)((TransformGroup)AssociatedObject.RenderTransform).Children[1]).CenterX = AssociatedObject.ActualWidth / 2;
        ((ScaleTransform)((TransformGroup)AssociatedObject.RenderTransform).Children[1]).CenterY = AssociatedObject.ActualHeight / 2;
        ((ScaleTransform)((TransformGroup)AssociatedObject.RenderTransform).Children[1]).ScaleY=-1;
    }

    protected override void OnDetaching()
    {
        base.OnDetaching();
        AssociatedObject.MouseEnter -= AssociatedObject_MouseEnter;
        AssociatedObject.MouseLeave -= AssociatedObject_MouseLeave;
    }
}

ViewModel.cs

public class ViewModel
{
    private ObservableCollection _dataSource = new ObservableCollection();

    public ViewModel()
    {
        _dataSource.Add("Cat");
        _dataSource.Add("Dog");
        _dataSource.Add("Mouse");
        _dataSource.Add("Owl");
        _dataSource.Add("Rabbit");
    }

    public IEnumerable DataSource
    {
        get { return _dataSource; }
    }
}

For more info, see this link:

Using Interactivity Behaviors and Actions in WPF/Silverlight Styles