Centrally handle the PointerEnteredEvent and PointerExitedEvent events?

[xiejiang2014]

There are many child elements in a Canvas, and I need to centrally handle the PointerEnteredEvent and PointerExitedEvent events of these child elements.

However, I found that the PointerEnteredEvent and PointerExitedEvent events are registered as RoutingStrategies.Direct instead of RoutingStrategies.Bubble

class InputElement:

/// <summary>
/// Defines the <see cref="E:Avalonia.Input.InputElement.PointerEntered" /> event.
/// </summary>
public static readonly RoutedEvent<PointerEventArgs> PointerEnteredEvent = RoutedEvent.Register<InputElement, PointerEventArgs>("PointerEntered", RoutingStrategies.Direct);

/// <summary>
/// Defines the <see cref="E:Avalonia.Input.InputElement.PointerExited" /> event.
/// </summary>
public static readonly RoutedEvent<PointerEventArgs> PointerExitedEvent = RoutedEvent.Register<InputElement, PointerEventArgs>("PointerExited", RoutingStrategies.Direct);

How should I handle this situation? Thank you.

[stevemonaco]

You can do hit detection of children yourself on the Canvas.PointerMoved event and track the hovered control. This is sometimes the better option depending on what kind of app you're writing.

Otherwise, you probably need to write an attached behavior for PointerEntered + PointerExited and apply them to each child control. These will either: 1. publish a message that you can listen to or 2. crawl up the visual tree to find the appropriate control and call a method on it. You can apply these to every child via style selector.