What is the best way to simulate a Click with MouseUp & MouseDown events or otherwise?

Question

In WPF most controls have MouseUp and MouseDown events (and the mouse-button-specific variations) but not a simple Click event that ca

Answer 1

Here is a behavior you can add to any element so that it will raise the ButtonBase.Click event using the normal button logic:

public class ClickBehavior : Behavior
{
    protected override void OnAttached()
    {
        AssociatedObject.MouseLeftButtonDown += (s, e) =>
        {
            e.Handled = true;
            AssociatedObject.CaptureMouse();
        };
        AssociatedObject.MouseLeftButtonUp += (s, e) =>
        {
            if (!AssociatedObject.IsMouseCaptured) return;
            e.Handled = true;
            AssociatedObject.ReleaseMouseCapture();
            if (AssociatedObject.InputHitTest(e.GetPosition(AssociatedObject)) != null)
                AssociatedObject.RaiseEvent(new RoutedEventArgs(ButtonBase.ClickEvent));
        };
    }
}

Notice the use of mouse capture/release and the input hit test check. With this behavior in place, we can write click handlers like this:

and the code behind:

    private void Rectangle_Click(object sender, RoutedEventArgs e)
    {
        Debug.WriteLine("Code-behind: Click");
    }

It's easy enough to convert this to all code-behind; the important part is the capture and click logic.

If you are not familiar with behaviors, install the Expression Blend 4 SDK and add this namespace:

xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"

and add System.Windows.Interactivity to your project.

Edit:

Here's how to attach the click behavior to an element in code-behind and add a handler for the click event:

void AttachClickBehaviors()
{
    AttachClickBehavior(rectangle1, new RoutedEventHandler(OnAttachedClick));
}

void OnAttachedClick(object sender, RoutedEventArgs e)
{
    Debug.WriteLine("Attached: Click");
}

// Reusable: doesn't need to be in the code-behind.
static void AttachClickBehavior(FrameworkElement element, RoutedEventHandler clickHandler)
{
    Interaction.GetBehaviors(element).Add(new ClickBehavior());
    element.AddHandler(ButtonBase.ClickEvent, clickHandler);
}