1 files changed, 101 insertions, 0 deletions
diff --git a/tests/untried/pos/gui.scala b/tests/untried/pos/gui.scala
new file mode 100644
index 000000000..0504fb435
--- /dev/null
+++ b/tests/untried/pos/gui.scala
@@ -0,0 +1,101 @@
+object Geom {
+  trait Shape
+  case class Point(x: Int, y: Int) extends Shape
+  case class Rectangle(ll: Point, ur: Point) extends Shape {
+    def inset(delta: Int) =
+      Rectangle(Point(ll.x - delta, ll.y - delta), Point(ur.x + delta, ur.y + delta));
+  }
+}
+
+object Color {
+  type Color = Int
+  val black = 0x000000
+  val grey  = 0x808080
+}
+
+trait Screen {
+  type Color = Int
+  def drawRect(r: Geom.Rectangle, c: Color): Unit
+  def fillRect(r: Geom.Rectangle, c: Color): Unit
+}
+
+object DummyScreen extends Screen {
+  def drawRect(r: Geom.Rectangle, c: Color): Unit = {
+    Console.println("draw " + r + " with " + c)
+  }
+  def fillRect(r: Geom.Rectangle, c: Color): Unit = {
+    Console.println("fill " + r + " with " + c)
+  }
+}
+
+object GUI {
+
+  object Controller {
+    def addMouseCtl(c: MouseCtl) = ()
+  }
+
+  trait Glyph {
+    def getRect: Geom.Rectangle
+    def setLoc(p: Geom.Point): Unit
+    def draw(): Unit = { Console.println("draw " + this) }
+  }
+
+  class Label(scr: Screen, p: Geom.Point, name: String) extends Glyph {
+    private var origin = p
+    def getRect = Geom.Rectangle(origin, origin).inset(10);
+    def setLoc(p: Geom.Point) = { origin = p }
+  }
+
+  trait Ctl {
+    def getGlyph: Glyph
+    def enable(b: Boolean): this.type
+  }
+
+  trait MouseCtl extends Ctl {
+    def mouseDown(p: Geom.Point): Unit
+  }
+
+  abstract class Button(scr: Screen, p: Geom.Point, name: String)
+  extends Glyph with MouseCtl {
+    var enabled: Boolean = false
+    val label = new Label(scr, p, name)
+
+    /* Glyph methods */
+    override def draw(): Unit = {
+      if (enabled) scr.drawRect(getRect, Color.black)
+      else scr.fillRect(getRect, Color.grey);
+      label.draw();
+    }
+    def setLoc(p: Geom.Point) = label.setLoc(p);
+    def getRect = label.getRect.inset(-2);
+
+    /* Ctl methods */
+    def enable(b: Boolean): this.type = { enabled = b; draw(); this }
+    def getGlyph = label
+    final def mouseDown(p: Geom.Point): Unit = {
+      if (enabled) doit() else Console.println("button is disabled");
+    }
+    /* deferred method to be specified by client */
+    def doit(): Unit
+  }
+}
+
+object GUIClient {
+
+  class App {
+    def quit(): Unit = { Console.println("application exited") }
+  }
+
+  class QuitButton (scr: Screen, p: Geom.Point, name: String, a: App)
+  extends GUI.Button(scr, p, name) {
+    def doit(): Unit = { a.quit() }
+  }
+
+  def main(args: Array[String]): Unit = {
+    val b = new QuitButton(
+      DummyScreen, Geom.Point(1, 1), "quit", new App);
+    b.draw();
+    b.enable(true).mouseDown(Geom.Point(1, 2));
+  }
+}
+