Interactions not trimming-friendly

[mysteryx93]

Using interactions breaks with Assembly Trimming. It's using reflection to access MediaFinished, and being defined on a 3rd party control, I won't be able to set attributes on that class.

<Interaction.Behaviors>
    <EventTriggerBehavior EventName="MediaFinished">
        <InvokeCommandAction Command="{Binding PlayNext}" />
    </EventTriggerBehavior>
</Interaction.Behaviors>

I always thought that MethodBinding was a much better way to do it; but couldn't get that to work in Avalonia.
https://github.com/mysteryx93/MethodBinding.Avalonia

What's the solution here?

[wieslawsoltes]

Using interactions breaks with Assembly Trimming. It's using reflection to access MediaFinished, and being defined on a 3rd party control, I won't be able to set attributes on that class.

<Interaction.Behaviors>
    <EventTriggerBehavior EventName="MediaFinished">
        <InvokeCommandAction Command="{Binding PlayNext}" />
    </EventTriggerBehavior>
</Interaction.Behaviors>

I always thought that MethodBinding was a much better way to do it; but couldn't get that to work in Avalonia. https://github.com/mysteryx93/MethodBinding.Avalonia

What's the solution here?

Convert event as routed and use

Avalonia.Xaml.Behaviors/src/Avalonia.Xaml.Interactions.Custom/RoutedEventTriggerBehavior.cs

Line 11 in 6280895

public class RoutedEventTriggerBehavior : Trigger<Interactive>

or create custom Behavior trigger.

[mysteryx93]

What's the difference with RoutedEventTriggerBehavior? That one doesn't rely on Reflection?

[mysteryx93]

OK I see, RoutedEvent property is set via a (compiled) binding. What's the recommended syntax to set that property to a RoutedEvent on the control though? Need to use some context-navigation syntax.

[mysteryx93]

It asks for a RoutedEvent; the RoutedEvent is static.

public static readonly RoutedEvent<RoutedEventArgs> StopCommandExecutedEvent =
    RoutedEvent.Register<MediaPlayerBase, RoutedEventArgs>(nameof(StopCommandExecuted), RoutingStrategies.Direct);
public event EventHandler<RoutedEventArgs>? StopCommandExecuted
{
    add => AddHandler(StopCommandExecutedEvent, value);
    remove => RemoveHandler(StopCommandExecutedEvent, value);
}

If I try to use like this

<RoutedEventTriggerBehavior RoutedEvent="{x:Static ui:MediaPlayer.StopCommandExecutedEvent}">

I get

MainView.axaml(131, 49): [AVLN:0004] Unable to resolve StopCommandExecutedEvent as static field, property, constant or enum value Line 131, position 49.

[mysteryx93]

Hah I was so close! This works. Need to call it on the base class.

<RoutedEventTriggerBehavior RoutedEvent="{x:Static ui:MediaPlayerBase.StopCommandExecutedEvent}">