Scala界面Pannel、Layout

object GUI_Panel_Layout extends SimpleSwingApplication{
    def top = new MainFrame {
      title = "Second GUI"
      val button = new Button {
        text = "Scala"
      }
      val label = new Label {
        text = "Here is Spark!!!"
      }
      contents = new BoxPanel(Orientation.Vertical) { //垂直布局
        contents += button
        contents += label
        border = Swing.EmptyBorder(50, 50, 50, 50)
      }
      
      listenTo(button) //监听button，解除监听为deafTO
      var clicks =0 
      reactions += { //处理事件
        case ButtonClicked(button) => { //偏函数匹配点击事件
          clicks += 1
          label.text = "Clicked " + clicks + " times"
          
        }
      }
    }
}

object GUI_Event extends SimpleSwingApplication  {

  val fileChooser = new FileChooser(new File("."))
  fileChooser.title = "File Chooser"
  val button = new Button {
    text = "Choose a File from local"
  }
  val label = new Label {
    text = "No any file selected yet."
  }
  val mainPanel = new FlowPanel {
    contents += button
    contents += label
  }
  def top = new MainFrame {
    title = "Scala GUI Programing advanced!!!"
    contents = mainPanel //mainPanel里有buuton、label

    listenTo(button) //监听button

    reactions += { //事件栈
      case ButtonClicked(b) => {
        val result = fileChooser.showOpenDialog(mainPanel) //打开对话框时指定父容器
        if (result == FileChooser.Result.Approve) { //如果选择了文件
          label.text = fileChooser.selectedFile.getPath() //修改label.text
        }
      }
    }
  }

}