如何为 javax.swing.Timer 编写 Scala 包装器 [英] How to write a Scala wrapper for javax.swing.Timer

问题描述

我想在 Scala Swing 应用程序中使用计时器.我可以使用Java版本，只是意味着我必须实现ActionListener接口.我宁愿使用 Scala Publishers/Reactors 模型来保持一致性，这样我就可以拥有 listenTo 计时器的东西.

I'd like to use a timer in a Scala Swing application. I can use the Java version, only it means I have to implement the ActionListener interface. I'd rather use the Scala Publishers / Reactors model for consistency, so I can have things that listenTo the timer.

这是我尝试过的:

class ScalaTimer(time: Int) extends Component {
  val t = new javax.swing.Timer(time, new java.awt.event.ActionListener {
    def actionPerformed(e: java.awt.event.ActionEvent) {
      publish(new scala.swing.event.ActionEvent(this))
    }
  })
  def start() {t.start()}
  def stop() {t.stop()}
  // etc

}

不起作用，因为 this 指的是 ActionListener 而不是 ScalaTimer 类.

Doesn't work because this refers to the the ActionListener rather than the ScalaTimer class.

另外，我可能不应该扩展 Component...我尝试了这个，因为我获得了发布者/反应器功能，但这并没有什么意义.我应该做这样的事情吗?如果是这样，我还需要包含其他特征吗?我如何知道必须实现哪些方法?

Also I probably shouldn't be extending Component... I tried this because I get the Publisher / Reactor functionality, but it doesn't really make sense. Should I do something like this instead? If so, are there other traits I need to include, and how do I know which methods I have to implement?

 class ScalaTimer extends javax.swing.Timer with Publisher {

(我的 IDE 立即标记方法 Timer(Int, ActionListener) 缺少参数"，这看起来有点奇怪，因为我没有调用方法.)

(My IDE immediately flags "Missing arguments for method Timer(Int, ActionListener)" which seems a bit weird since I haven't invoked a method.)

推荐答案

执行此操作的规范方法是在要引用的事物(通常是 self 除非已经被占用了):

The canonical way to do this is to introduce an alias at the top of the thing you want to refer to (usually self unless that's already taken):

class ScalaTimer(time: Int) extends Component {
  self =>
  val t = ...
    publish(new scala.swing.event.ActionEvent(self))
  ...

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