Merged changes from Andy Hicks, mostly having to do with createImageIcon.

Author: Allan Jacobs

examples/src/main/scala/scala/swing/examples/tutorials/components/ButtonDemo.scala

@@ -47,28 +47,28 @@ import javax.swing.UIManager
  *   /scala/swing/examples/tutorials/images/left.gif
  */
 class ButtonDemo extends FlowPanel {
-  val leftButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/right.gif").get
-  val middleButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/middle.gif").get
-  val rightButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/left.gif").get
-  //
+  val leftButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/right.gif")
+  val middleButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/middle.gif")
+  val rightButtonIcon = ButtonDemo.createImageIcon("/scala/swing/examples/tutorials/images/left.gif")
+
   val disable: Button = new Button("Disable middle button") {
-    icon = leftButtonIcon
+    leftButtonIcon.foreach(  icon = _)
     verticalTextPosition = Alignment.Center
     horizontalTextPosition = Alignment.Leading
     mnemonic = event.Key.D
     tooltip = "Click this button to disable the middle button."
   }
-  //
+
   val middle: Button = new Button("Middle button") {
-    icon = middleButtonIcon
+    middleButtonIcon.foreach(  icon = _ )
     verticalTextPosition = Alignment.Bottom
     horizontalTextPosition = Alignment.Center
     mnemonic = event.Key.M
     tooltip = "This middle button does nothing when you click it."
   }
-  //
+
   val enable: Button = new Button("Enable middle button") {
-    icon = rightButtonIcon
+    rightButtonIcon.foreach( icon = _  )
     enabled = false
     mnemonic = event.Key.E
     tooltip = "Click this button to enable the middle button."
@@ -82,16 +82,17 @@ class ButtonDemo extends FlowPanel {
   listenTo(enable)
 
   reactions += {
-    case ButtonClicked(`enable`) => enableMiddle
-    case ButtonClicked(`disable`) => disableMiddle
+    case ButtonClicked(`enable`) => enableMiddle()
+    case ButtonClicked(`disable`) => disableMiddle()
   }
 
   def enableMiddle(): Unit = {
     enable.enabled = false
     middle.enabled = true
     disable.enabled = true
   }
-  def disableMiddle(): Unit = {
+
+  def disableMiddle(): Unit  = {
     enable.enabled = true
     middle.enabled = false
     disable.enabled = false

examples/src/main/scala/scala/swing/examples/tutorials/components/ButtonHtmlDemo.scala

@@ -111,6 +111,6 @@ object ButtonHtmlDemo extends SimpleSwingApplication {
   lazy val top = new MainFrame() {
     title = "ButtonHtmlDemo"
     //Create and set up the content pane.
-    contents = new ButtonHtmlDemo();
+    contents = new ButtonHtmlDemo()
   }
 }

examples/src/main/scala/scala/swing/examples/tutorials/components/CheckboxDemo.scala

@@ -34,8 +34,8 @@ import scala.swing._
 import scala.swing.event.ButtonClicked
 import scala.swing.event.Key
 import java.awt.Font
-import javax.swing.ImageIcon
-import java.net.URL
+
+import scala.swing.examples.tutorials.components.ButtonDemo._
 
 /**
  * Tutorial: How to Use Buttons, Check Boxes, and Radio Buttons
@@ -83,21 +83,25 @@ class CheckboxDemo extends BorderPanel {
      */
 
   //Create the check boxes.
-  val chinButton = new CheckBox("Chin")
-  chinButton.mnemonic = Key.C // .VK_C
-  chinButton.selected = true
+  val chinButton = new CheckBox("Chin") {
+    mnemonic = Key.C // .VK_C
+    selected = true
+  }
 
-  val glassesButton = new CheckBox("Glasses")
-  glassesButton.mnemonic = Key.G;
-  glassesButton.selected = true
+  val glassesButton = new CheckBox("Glasses") {
+    mnemonic = Key.G
+    selected = true
+  }
 
-  val hairButton = new CheckBox("Hair")
-  hairButton.mnemonic = Key.H
-  hairButton.selected = true
+  val hairButton = new CheckBox("Hair") {
+    mnemonic = Key.H
+    selected = true
+  }
 
-  val teethButton = new CheckBox("Teeth")
-  teethButton.mnemonic = Key.T
-  teethButton.selected = true
+  val teethButton = new CheckBox("Teeth") {
+    mnemonic = Key.T
+    selected = true
+  }
 
   //Indicates what's on the geek.
   val choices: StringBuffer = new StringBuffer("cght")
@@ -125,34 +129,31 @@ class CheckboxDemo extends BorderPanel {
   listenTo(hairButton)
   listenTo(teethButton)
 
+
+  def changeState( idx:Int, checkBox: CheckBox, label:Char ): Unit = {
+    choices.setCharAt(idx, if (checkBox.selected) label else '-' )
+    updatePicture()
+  }
+
   reactions += {
-    case ButtonClicked(`chinButton`) =>
-      choices.setCharAt(0, if (!chinButton.selected) '-' else 'c')
-      updatePicture()
-    case ButtonClicked(`glassesButton`) =>
-      choices.setCharAt(1, if (!glassesButton.selected) '-' else 'g')
-      updatePicture()
-    case ButtonClicked(`hairButton`) =>
-      choices.setCharAt(2, if (!hairButton.selected) '-' else 'h')
-      updatePicture()
-    case ButtonClicked(`teethButton`) =>
-      choices.setCharAt(3, if (!teethButton.selected) '-' else 't')
-      updatePicture()
+    case ButtonClicked(`chinButton`) => changeState(0, chinButton, 'c')
+    case ButtonClicked(`glassesButton`) => changeState(1, glassesButton, 'g')
+    case ButtonClicked(`hairButton`) => changeState(2, hairButton, 'h')
+    case ButtonClicked(`teethButton`) => changeState(3, teethButton, 't')
   }
 
   def updatePicture(): Unit = {
+    pictureLabel.tooltip = choices.toString
+
     //Get the icon corresponding to the image.
-    val s = choices.toString()
-    val icon: Option[ImageIcon] = CheckboxDemo.createImageIcon(
-      "/scala/swing/examples/tutorials/images/geek/geek-"
-        + choices.toString()
-        + ".gif")
-    pictureLabel.icon = if (icon.isDefined) icon.get else Swing.EmptyIcon
-    pictureLabel.tooltip = choices.toString()
-    if (icon == null) {
-      pictureLabel.text = "Missing Image"
-    } else {
-      pictureLabel.text = null
+    createImageIcon( s"/scala/swing/examples/tutorials/images/geek/geek-$choices.gif") match {
+      case Some( icon ) =>
+        pictureLabel.icon = icon
+        pictureLabel.text = null
+      case None =>
+        pictureLabel.icon = Swing.EmptyIcon
+        pictureLabel.text = "Missing Image"
+
     }
   }
 }
@@ -165,6 +166,6 @@ object CheckboxDemo extends SimpleSwingApplication {
   lazy val top = new MainFrame() {
     title = "CheckboxDemo"
     //Create and set up the content pane.
-    contents = new CheckboxDemo();
+    contents = new CheckboxDemo()
   }
 }

examples/src/main/scala/scala/swing/examples/tutorials/components/ColorChooserDemo.scala

@@ -41,12 +41,10 @@ import java.awt.{ Color, Dimension, Font }
  * 
  * Source code reference:
  * [[http://docs.oracle.com/javase/tutorial/uiswing/examples/components/ColorChooserDemoProject/src/components/ColorChooserDemo.java]]
- *
- * ColorChooserDemo.scala requires no other files.
  */
 class ColorChooserDemo extends BorderPanel {
   //Set up the banner at the top of the window
-  val banner = new Label("Welcome to the Tutorial Zone!", EmptyIcon, Alignment.Center) {
+  val banner = new Label("Welcome to the Scala-Swing Zone!", EmptyIcon, Alignment.Center) {
     foreground = Color.yellow
     background = Color.blue
     opaque = true
@@ -75,6 +73,6 @@ object ColorChooserDemo extends SimpleSwingApplication {
   lazy val top = new MainFrame() {
     title = "ColorChooserDemo"
     //Create and set up the content pane.
-    contents = new ColorChooserDemo();
+    contents = new ColorChooserDemo()
   }
 }

examples/src/main/scala/scala/swing/examples/tutorials/components/ComboBoxDemo.scala

@@ -32,10 +32,10 @@
 package scala.swing.examples.tutorials.components
 
 import scala.swing._
-import scala.swing.event.{ SelectionChanged }
+import scala.swing.event.SelectionChanged
 import java.awt.{ Dimension, Font }
-import javax.swing.{ BorderFactory, ImageIcon }
-import java.net.URL
+import javax.swing.BorderFactory
+
 
 /**
  * Tutorial: How to Use Combo Boxes
@@ -55,10 +55,10 @@ class ComboBoxDemo extends BorderPanel {
   }
 
   //Set up the picture label.
-  val imgIcon = ComboBoxDemo.createImageIcon("/scala/swing/examples/tutorials/images/"
-    + petList.selection.item + ".gif")
+  val imgIcon = ComboBoxDemo.createImageIcon(s"/scala/swing/examples/tutorials/images/${petList.selection.item}.gif")
+
   val picture = new Label() {
-    icon = if (imgIcon.isDefined) imgIcon.get else Swing.EmptyIcon
+    icon = imgIcon.getOrElse( Swing.EmptyIcon )
     font = font.deriveFont(Font.ITALIC)
     horizontalAlignment = Alignment.Center
     //The preferred size is hard-coded to be the width of the
@@ -78,25 +78,20 @@ class ComboBoxDemo extends BorderPanel {
   }
 
   def updateLabel(s: String): Unit = {
-    val ic = ComboBoxDemo.createImageIcon("/scala/swing/examples/tutorials/images/" + s + ".gif")
-    picture.icon = if (ic.isDefined) imgIcon.get else Swing.EmptyIcon
+    picture.icon =
+      ComboBoxDemo.createImageIcon("/scala/swing/examples/tutorials/images/" + s + ".gif").getOrElse( Swing.EmptyIcon )
   }
 }
 
 object ComboBoxDemo extends SimpleSwingApplication {
-  val birdString = "Bird"
-  val catString = "Cat"
-  val dogString = "Dog"
-  val rabbitString = "Rabbit"
-  val pigString = "Pig"
 
-  /** Returns an ImageIcon, or null if the path was invalid. */
-  def createImageIcon(path: String): Option[javax.swing.ImageIcon] = {
+  /** Returns an ImageIcon option, or None if the path was invalid. */
+  def createImageIcon(path: String ): Option[javax.swing.ImageIcon] =
     Option(resourceFromClassloader(path)).map(imgURL => Swing.Icon(imgURL))
-  }
+
   lazy val top = new MainFrame() {
     title = "ComboBoxDemo"
     //Create and set up the content pane.
-    contents = new ComboBoxDemo();
+    contents = new ComboBoxDemo()
   }
 }

examples/src/main/scala/scala/swing/examples/tutorials/components/ComboBoxDemo2.scala

@@ -37,14 +37,15 @@ import java.awt.Color
 import java.util.Date
 import java.text.SimpleDateFormat
 
+
+import scala.util.{Try, Failure, Success}
+
 /**
  * Tutorial: How to Use Combo Boxes
  * [[http://docs.oracle.com/javase/tutorial/uiswing/components/combobox.html]]
  * 
  * Source code reference:
  * [[http://docs.oracle.com/javase/tutorial/uiswing/examples/components/ComboBoxDemo2Project/src/components/ComboBoxDemo2.java]]
- *
- * ComboBoxDemo2.scala requires no other files.
  */
 class ComboBoxDemo2 extends BoxPanel(Orientation.Vertical) {
   val patternExamples = Array[String](
@@ -85,14 +86,14 @@ class ComboBoxDemo2 extends BoxPanel(Orientation.Vertical) {
   val patternPanel = new BoxPanel(Orientation.Vertical) {
     contents += patternLabel1
     contents += patternLabel2
-    xLayoutAlignment = 0.0 // Left
+    xLayoutAlignment =  java.awt.Component.LEFT_ALIGNMENT
     contents += patternList
   }
 
   val resultPanel = new GridPanel(0,1) {
     contents += resultLabel
     contents += result
-    xLayoutAlignment = 0.0 // Left
+    xLayoutAlignment = java.awt.Component.LEFT_ALIGNMENT
   }
 
   contents += patternPanel
@@ -102,21 +103,20 @@ class ComboBoxDemo2 extends BoxPanel(Orientation.Vertical) {
 
   listenTo(patternList.selection)
   reactions += {
-    case SelectionChanged(`patternList`) => // currentPattern = patternList.selection.item
-    reformat()
+    case SelectionChanged(`patternList`) => reformat()
   }
 
   def reformat(): Unit = {
-    val today = new Date()
-    val formatter = new SimpleDateFormat(patternList.selection.item)
-    try {
-      val dateString = formatter.format(today)
-      result.foreground = Color.black
-      result.text = dateString
-    }
-    catch {
-      case iae: IllegalArgumentException => result.foreground = Color.red
-        result.text = "Error: " + iae.getMessage()
+    Try {
+      val today = new Date()
+      val formatter = new SimpleDateFormat(patternList.selection.item)
+      formatter.format(today)
+    } match {
+      case Success( dateString) =>
+        result.foreground = Color.black
+        result.text = dateString
+      case Failure( err ) =>
+        result.text = s"Error: ${err.getMessage}"
     }
   }
 }
@@ -125,6 +125,6 @@ object ComboBoxDemo2 extends SimpleSwingApplication {
   lazy val top = new MainFrame() {
     title = "ComboBoxDemo2"
     //Create and set up the content pane.
-    contents = new ComboBoxDemo2();
+    contents = new ComboBoxDemo2()
   }
 }