hey, apologies if this has been answered a thousan...

# announcements

[Mike Patterson]

hey, apologies if this has been answered a thousand times, but is there a preferred solution to handling multiple listeners that can be added to one class?

private class MyAdListener(private val listeners: List<AdListener>) : AdListener {
    override fun onAdStarted(adInfo: AdInfo) = listeners.forEach { it.onAdStarted(adInfo) }
    override fun onAdCompleted(adInfo: AdInfo) = listeners.forEach { it.onAdCompleted(adInfo) }
    override fun onAdBreakStarted(adInfo: AdInfo) = listeners.forEach { it.onAdBreakStarted(adInfo) }
    override fun onAdBreakCompleted(adInfo: AdInfo) = listeners.forEach { it.onAdBreakCompleted(adInfo) }
    // etc

is there a method for delegation that works? something like...

private class MyAdListener(private val listeners: List<AdListener>) : AdListener by listeners.each()

[Zach Klippenstein (he/him) [MOD]]

Nope, but I would probably expose a Flow instead of a manual listener api.

[Mike Patterson]

thanks, looking at ways to restructure this

[James Richardson]

You can implement this with a dynamic proxy, to implement all methods of an interface in handle(), that just delegates the invoked method and its arguments to each listener in turn. It will be perfectly performant for almost all use cases.