is there a neater way to conditionally apply modifiers than

Question

is there a neater way to conditionally apply modifiers than ```modifier = modifier let if canBeExpanded it clickable expanded = expanded else it ```

Francesc · Answer

you can use `then` ```modifier = modifier then if condition Modifier clickable else MOdifier ```

xxfast · Answer

not sure if that s any neater though ```modifier = modifier then if canBeExpanded Modifier clickable expanded = expanded else Modifier run if canBeExpanded clickable expanded = expanded else this ``` trying to avoid that `else` part `apply` compiles but doesn t seem to work not sure why ``` apply if canBeExpanded clickable expanded = expanded ```

Francesc · Answer

if you have complex logic you might want to consider an extension function or using `composed`

Francesc · Answer

for simple logic `then` seems to be the preferred approach if you check the compose code that s what it uses under the hood for instance ``` Stable Suppress ModifierInspectorInfo fun Modifier fillMaxWidth FloatRange from = 0 0 to = 1 0 fraction Float = 1f = this then if fraction == 1f FillWholeMaxWidth else createFillWidthModifier fraction ```

xxfast · Answer

Extension like this ```fun Modifier on condition Boolean block Modifier gt Modifier Modifier = if condition block else this``` can make the call site look like ```modifier = modifier on canBeExpanded clickable expanded = expanded ``` but this comes at the cost of indirection i guess

Francesc · Answer

in your particular case couldn t you always have the clickable modifier and then use `enabled` to control whether it s actually clickable

xxfast · Answer

how so

Francesc · Answer

using this version of `clickable` ```fun Modifier clickable enabled Boolean = true onClickLabel String = null role Role = null onClick gt Unit ```

Francesc · Answer

with `enabled = condition`

xxfast · Answer

ah much simpler +1 thanks

agrosner · Answer

``` Convenience for modifiers that should only apply if condition is true elseFn useful for conditional else logic inline fun Modifier thenIf condition Boolean modifierFn Modifier gt Modifier = this let if condition it modifierFn else it Convenience for modifiers that should only apply if condition is true elseFn useful for conditional else logic inline fun Modifier thenIf condition Boolean modifierFn Modifier gt Modifier elseFn Modifier gt Modifier = this let if condition it modifierFn else it elseFn ```

agrosner · Answer

we use these functions extensively for this specific use case

Colton Idle · Answer

I asked about something similar a while back <https kotlinlang slack com archives CJLTWPH7S p1638332547357800>

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

For the record `apply` doesn t work because apply returns its receiver not the last expression in the lambda You d want `run` or `let`