IntelliJ shows error using scalatags with boolean attributes

Question

Does anyone now why IntelliJ is showing an error here even though sbt compiles and everything works correctly:

*Edit: "stopEnabled" is a Boolean.

As I understand, to not show an error here, I would have to write someting like this:

button(if(!stopEnabled) disabled else JsDom.Modifier.*nothing*)

Is there any way of solving this nicely?

Answer 1

disabled is a nuisance -- IMO, they spec'ed it wrong from the beginning, and have never made it better.

Offhand, I would guess that Scalatags' frag() constructor is probably the easiest solution: that takes its parameters and wraps them as a single frag. I believe that works even if there are no parameters. So I think you could do:

div(
  if (stopEnabled)
    frag()
  else
    disabled := "disabled"
)

Answer 2

You can do it with a sequence:

import scalatags.JsDom.all._

val stopEnabled = true

val modifiers = if(stopEnabled) Nil else Seq(disabled)

div(
  button(modifiers)
)