Example of JavaFX ChangeListener in Scala

by hohonuuli 10/31/2012 10:42:00 AM 0 comments

I normally use IntelliJ IDEA and it's excellent Scala plugin for Scala development*. However, IntelliJ gave me a truly bogus autocomplete suggestion while adding a ChangeListener to a JavaFX Property referencing a Node:

Does Not Compile

What IntelliJ giveth:

nodeProperty.addListener(new ChangeListener[_ >: Node] {
  def changed(p1: ObservableValue[_ <: _ >: Node], p2: _ >: Node, p3: _ >: Node) {}
})

Compiles

I had to change it to the following:

nodeProperty.addListener(new ChangeListener[Node] {
  def changed(p1: ObservableValue[_ <: Node], p2: Node, p3: Node) {}
})

* A footnote about developing with Scala. I normally build projects with Maven. The very excellent scala-maven-plugin, when used along-side zinc and mvnsh make for very quick code-compile cycles.

I also sometimes use SBT/ensime/Sublime Text. However, SBT and I usually agree to disagree. Fortunately, for many projects creating a dual Maven/SBT build is relatively straightforward.