Hello I have an array of functions that accepts a ...

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[robinchew]

Hello I have an array of functions that accepts a View argument:

val manyFunctions: ArrayList<(View) -> Unit> = arrayListOf(
    {layout: TextView -> Unit}
)

But that don't work cos TextView is not exactly View though it subclasses it.

[Dominaezzz]

Change View to out View or in View. I don't remember which will work but one should.

[diesieben07]

Yes, your function does not accept View, it only accepts TextView. How do you intend to even call these functions? You can't.

@Dominaezzz That does not work in a function type (it's not really useful, the parameters are always in, the return type is always out).

[Dominaezzz]

Oh true.

[robinchew]

Why can't you call them? Functions are meant to be called.

[Dominaezzz]

What argument would you pass?

[robinchew]

An instance of a View type

[diesieben07]

If you had a (theoretical) { foo: out Thing -> Unit } there is no way to call it, since you cannot know what it's actual parameter is.

[robinchew]

Ok I think I'm back to the same discussion I had with Shawn yesterday

[Dominaezzz]

If you pass on anything that isn't a TextView, you'll get a ClassCastException or similar. Given it compiles.

[diesieben07]

It will only compile with an "unchecked cast" warning

[robinchew]

Thanks guys for the clues, I think I know where to go.

[robinchew]

I hit a wall again, so instead of doing:

ArrayList<(View) -> Unit>

I tried to do:

ArrayList<((Context) -> View) -> Unit>

But that's a syntax error

[robinchew]

I basically substituted View for (Context) -> View.

[robinchew]

oh wait, it works? must be bracket problems

[robinchew]

nevermind it doesn't make sense anyway