build.sbt

name := "scalaswing"

version := "1.0"

scalaVersion := "2.11.5"

Hello.scala

import scala.swing._

object Hello extends SimpleSwingApplication {
  def top = new MainFrame {
    title = "Hello world"
    contents = new Label("Hello world")
  }
}

project - build.properties

sbt.version = 0.13.5

sbt compile

% sbt compile
Picked up _JAVA_OPTIONS: -Dfile.encoding=UTF-8
[info] Loading project definition from /Users/cake/IdeaProjects/scalaswing/project
[info] Set current project to scalaswing (in build file:/Users/cake/IdeaProjects/scalaswing/)
[info] Updating {file:/Users/cake/IdeaProjects/scalaswing/}scalaswing...
[info] Resolving jline#jline;2.12 ...
[info] Done updating.
[info] Compiling 1 Scala source to /Users/cake/IdeaProjects/scalaswing/target/scala-2.11/classes...
[error] /Users/cake/IdeaProjects/scalaswing/src/main/scala/Hello.scala:1: object swing is not a member of package scala
[error] import scala.swing._
[error]              ^
[error] /Users/cake/IdeaProjects/scalaswing/src/main/scala/Hello.scala:3: not found: type SimpleSwingApplication
[error] object Hello extends SimpleSwingApplication {
[error]                      ^
[error] /Users/cake/IdeaProjects/scalaswing/src/main/scala/Hello.scala:4: not found: type MainFrame
[error]   def top = new MainFrame {
[error]                 ^
[error] /Users/cake/IdeaProjects/scalaswing/src/main/scala/Hello.scala:5: not found: value title
[error]     title = "Hello world"
[error]     ^
[error] /Users/cake/IdeaProjects/scalaswing/src/main/scala/Hello.scala:6: not found: value contents
[error]     contents = new Label("Hello world")
[error]     ^
[error] 5 errors found
[error] (compile:compile) Compilation failed
[error] Total time: 4 s, completed 2015/02/11 14:59:19