need a return type, i suppose :D

assignments/a2/src/main/java/Menubar.java

@@ -16,7 +16,7 @@ public class Menubar extends JPanel implements Observer
     model.addObserver(this);
   }
   
-  public updateColour()
+  public void updateColour()
   {
     this.setbackground(Color.BLUE);
     this.update(model);