I'm trying to create a <Google Chromecast Custom R...

# javascript

[mkosm]

I'm trying to create a Google Chromecast Custom Receiver using KotlinJS.

I downloaded the chromecast-caf-receiver TypeScript declaration files from DefinitelyTyped. and converted them to Kotlin using dukat. After some modifications to get the output from dukat to compile, I came up with the attached files.

Question: I need to get an instance of CastReceiverContext by calling cast.framework.CastReceiverContext.getInstance(). In order to do that, I've done this:

external object cast {
    var framework: Framework
}

external object Framework {
    var CastReceiverContext: CastReceiverContextStatic
}

external open class CastReceiverContextStatic() {
    fun getInstance(): CastReceiverContext
}

// access it using:
val context = cast.framework.CastReceiverContext.getInstance()

This works, but I feel like there is a better way to do this. Is there?

cast.zip

[Robert Jaros]

Not sure if better, but shorter:

external val cast: dynamic
val context: CastReceiverContext = cast.framework.CastReceiverContext.getInstance()

[mkosm]

That looks neater, thanks!

I actually originally tried this:

external val cast: dynamic
val context = cast.framework.CastReceiverContext.getInstance() as CastReceiverContext

but I was getting ReferenceError: CastReceiverContext is not defined. I didn't know that specifying the type while declaring a dynamic variable is different than casting it.

[Robert Jaros]

actually I don't know how is CastReceiverContext type defined in your project, because it's not defined in your sample

[Robert Jaros]

I assumed it is defined elsewhere

[Robert Jaros]

if you do a cast the compiler probably generates some kind of check and throws an error

[Robert Jaros]

if you just assign a dynamic variable you get an unchecked cast warning in IDE, and there is no check at runtime

[mkosm]

ah, I see

[Robert Jaros]

at least thats how I think it is 🙂 haven't tested this :)

[mkosm]

here is CastReceiverContext by the way

CastReceiverContext