Hi to all How I can shadow unused function argument kotlinlang #announcements

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Denis A

08/13/2018, 10:49 AM

Hi to all! How I can shadow unused function argument?

gildor

08/13/2018, 10:50 AM

Only by suppressing this warning for this argument or for this function

why do you need this unused argument?

Denis A

08/13/2018, 10:52 AM

I set this function on clickListeners

https://monosnap.com/file/dhkHwJCp5ErSgvOsddTIV1lKEP19FN

karelpeeters

08/13/2018, 10:52 AM

Maybe if you call it

➖ 1

Denis A

08/13/2018, 10:53 AM

I can use lambdas, but (i think) this syntax more friendly and works faster

gildor

08/13/2018, 10:54 AM

For click listener it’s different, you can use

for lamba params, but not for function params

karelpeeters

08/13/2018, 10:54 AM

But what if you're implementing an interface for example? Is the warning surpressed automatically then?

Denis A

08/13/2018, 10:54 AM

yes, _ , __, _ - reserved words

gildor

08/13/2018, 10:55 AM

I would just use lambda instead of adding useless param, imo it’s bad style to add useless params for such case

yes, _ , __, _ - reserved words

For function params, not for lambda arguments

➕ 1

why not just use:

setOnClickListener { logic.okPress() }

yes, method reference is more idiomatic, but if you need add useless param, I would say that it’s become much less idiomatic

Denis A

08/13/2018, 10:56 AM

too many brackets)

gildor

08/13/2018, 10:56 AM

one more sulution to add custom

setOnClickListener

extension function without argumentyt

fun View.onClick(action: () -> Unit)

so you can now use it with functions without arguments: button.onClick(logic::okPress)

or even with the same name:

inline fun View.setOnClickListener(crossinline listener: () -> Unit) {
    setOnClickListener { listener() }
}

Denis A

08/13/2018, 11:00 AM

apparently, this is the only way

gildor

08/13/2018, 11:00 AM

so now you can use it with method reference without additional changes

Denis A

08/13/2018, 11:00 AM

but i add one lambda

gildor

08/13/2018, 11:00 AM

No, function is inlined, no overhead in this case

Denis A

08/13/2018, 11:04 AM

thanks)

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