在Slider和min / max TextField之间的Bind Directional策略之后，在TextField输入上过滤用户值

Question

使用两个TextField：texMin和texMax，我想限制我的doubleSlider控件的最小值和最大值（参见自定义ui控件DoubleSlider：{{ 3}}）

DoubleBinded with StringConverter（double to string）工作正常，但现在我不知道如何过滤以获得用户在TextField后的ENTER中输入的正确值setOnKeyReleasedEvent ..

我不知道用户输入的值bindBidirectional过滤器是否可以使用bindBidirectional属性。我认为 def sliderBlockFactory(slider: DoubleSlider): HBox = { val minText = new TextField() val maxText = new TextField() minText.setText(slider.getValue1().toString) maxText.setText(slider.getValue2().toString) slider.value1Property().addListener( new ChangeListener[Number]() { override def changed(ov: ObservableValue[_ <: Number], old_val: Number, new_val: Number) { if (new_val.doubleValue() == null) { minText.setText("") } else { minText.setText(new_val.doubleValue().toString()) } } }) slider.value2Property().addListener( new ChangeListener[Number]() { override def changed(ov: ObservableValue[_ <: Number], old_val: Number, new_val: Number) { if (new_val.doubleValue() == null) { maxText.setText("") } else { maxText.setText(new_val.doubleValue().toString()) } } }) minText.setPrefWidth(40) maxText.setPrefWidth(40) val converter: StringConverter[_ <: Number] = new DoubleStringConverter() Bindings.bindBidirectional(minText.textProperty(), slider.value1Property(), converter.asInstanceOf[StringConverter[Number]]) Bindings.bindBidirectional(maxText.textProperty(), slider.value2Property(), converter.asInstanceOf[StringConverter[Number]]) val uiSliderBlock = new HBox() uiSliderBlock.getChildren.addAll(minText, slider, maxText) uiSliderBlock } def doubleSliderFactory(min: Double, max: Double): DoubleSlider = { val slider = new DoubleSlider() slider.setMin(min) slider.setMax(max) slider.setShowTickLabels(true) slider.setShowTickMarks(true) slider.setMajorTickUnit(50) slider.setMinorTickCount(25) slider.setSnapToTicks(true) slider.setPrefWidth(100) slider.setBlockIncrement(10) slider } val myDoubleSlider = sliderBlockFactory(doubleSliderFactory(0.0, 100.0)) 绕过我的过滤器（每次文本更改时触发一个事件），但我不确定。

class DoubleTextField(var minValue: Double, var maxValue: Double, val initialValue: Double) extends TextField {

  require(minValue < maxValue, "DoubleField min value " + minValue + " greater than max value " + maxValue)
  require(maxValue > minValue, "DoubleField max value " + minValue + " less than min value " + maxValue)
  //require(!((minValue <= initialValue) && (initialValue <= maxValue)), "DoubleField initialValue " + initialValue + " not between " + minValue + " and " + maxValue)

  val value: DoubleProperty = new SimpleDoubleProperty(initialValue)

  //scala parsing
  def parseDouble(s: String) = try {
    Some(s.toDouble)
  } catch {
    case _ ⇒ None
  }

  def getValue() = value.getValue()

  def setValue(newValue: Double) = value.setValue(newValue)

  def valueProperty(): DoubleProperty = value

  setText(initialValue.toString())

  val doubleField: DoubleTextField = this

  // make sure the value property is clamped to the required range
  // and update the field's text to be in sync with the value.
  value.addListener(new ChangeListener[Number]() {
    override def changed(observableValue: ObservableValue[_ <: Number], oldValue: Number, newValue: Number) {
      if (newValue == null) {
        doubleField.setText("")
      } else {
        if (newValue.doubleValue() < doubleField.minValue) {
          value.setValue(doubleField.minValue)
          return
        }

        if (newValue.doubleValue() > doubleField.maxValue) {
          value.setValue(doubleField.maxValue)
          return
        }

        if (newValue.doubleValue() == 0 && (textProperty().get() == null || "".equals(textProperty().get()))) {
          // no action required, text property is already blank, we don't need to set it to 0.
        } else {
          doubleField.setText(newValue.toString())
        }
      }
    }
  })

  // restrict key input to numerals.
  this.addEventFilter(KeyEvent.KEY_TYPED, new EventHandler[KeyEvent]() {
    override def handle(keyEvent: KeyEvent) {
      if (!"0123456789".contains(keyEvent.getCharacter())) {
        keyEvent.consume()
      }
    }
  })

  // i don't want a realtime change on my textfield,
  // so i prefer a validate method like focusedProperty (see below)
  /*this.textProperty().addListener(
    new ChangeListener[String]() {
      override def changed(observableValue: ObservableValue[_ <: String], oldValue: String, newValue: String) {
        if (newValue == null || "".equals(newValue)) {
          value.setValue(0)
          return
        }

        parseDouble(newValue) match {
          case Some(d: Double) ⇒
            if (doubleField.minValue > d || d > doubleField.maxValue) {
              textProperty().setValue(oldValue)
              value.set(oldValue.toDouble)
            } else {
              value.set(d)
            }
          case _ ⇒ oldValue //reset to old value
        }

      }
    })*/

  // Detect a change in focus on the text field.. If we lose the focus we take appropriate action
  // problem with boolean : https://stackoverflow.com/questions/11377350/scala-java-interop-class-type-not-converted
  this.focusedProperty().addListener(
    new ChangeListener[java.lang.Boolean]() { db ⇒
      override def changed(observable: ObservableValue[_ <: java.lang.Boolean], oldValue: java.lang.Boolean, newValue: java.lang.Boolean) {
        if (!newValue) {
          parseDouble(doubleField.textProperty().get()) match {
            case Some(d: Double) ⇒
              if (doubleField.minValue > d || d > doubleField.maxValue) {
                textProperty().setValue(doubleField.minValue.toString)
                value.set(textProperty().get().toDouble)
              } else {
                value.set(d)
              }
            case _ ⇒ println("error") //reset to old value
          }
        }
      }
    })

}

更新1：

感谢评论，我修改了我的代码源。 我放弃了DoubleStringConverter，因为我的用例太复杂了。 我还将注释url中给出的java源代码翻译成scala：

DoubleSlider

DoubleTextField更新// inspired by : // https://gist.github.com/1962045 // https://stackoverflow.com/questions/14138082/java-fx-bidirectional-bindings-of-different-properties // https://forums.oracle.com/forums/thread.jspa?threadID=2311243 def sliderBlockFactory(slider: DoubleSlider): HBox = { val minText = new DoubleTextField(slider.getMin, slider.getMax, slider.getMin) val maxText = new DoubleTextField(slider.getMin, slider.getMax, slider.getMax) slider.value1Property().addListener( new ChangeListener[Number]() { override def changed(ov: ObservableValue[_ <: Number], old_val: Number, new_val: Number) { if (new_val.doubleValue() == null) { minText.setText("") } else { //set new min value of maxText maxText.minValue = new_val.doubleValue() } } }) slider.value2Property().addListener( new ChangeListener[Number]() { override def changed(ov: ObservableValue[_ <: Number], old_val: Number, new_val: Number) { if (new_val.doubleValue() == null) { maxText.setText("") } else { //set new max value of minText minText.maxValue = new_val.doubleValue() } } }) minText.setPrefWidth(40) maxText.setPrefWidth(40) /*val converter: StringConverter[_ <: Number] = new DoubleStringConverter() Bindings.bindBidirectional(minText.textProperty(), slider.value1Property(), converter.asInstanceOf[StringConverter[Number]]) Bindings.bindBidirectional(maxText.textProperty(), slider.value2Property(), converter.asInstanceOf[StringConverter[Number]]) */ minText.valueProperty().bindBidirectional(slider.value1Property()) maxText.valueProperty().bindBidirectional(slider.value2Property()) val uiSliderBlock = new HBox() uiSliderBlock.getChildren.addAll(minText, slider, maxText) uiSliderBlock } def doubleSliderFactory(min: Double, max: Double): DoubleSlider = { val slider = new DoubleSlider() slider.setMin(min) slider.setMax(max) slider.setShowTickLabels(true) slider.setShowTickMarks(true) slider.setMajorTickUnit(50) slider.setMinorTickCount(25) slider.setSnapToTicks(true) slider.setPrefWidth(100) slider.setBlockIncrement(10) slider } val myDoubleSlider = sliderBlockFactory(doubleSliderFactory(0.0, 100.0)) 的更正代码来源：

changeListener

结果:)

此代码有效，每个滑块控件的最小值和最大值都会正确更新，但正如您所看到的，当焦点离开且值不好时我无法通过焦点事件检索旧值< / strong>即可。我的问题很简单，有没有办法在textProperty上使用{{1}}而在textField中获取旧值？

更新2：

我在这里找到了答案：

http://code.google.com/p/javafx-widgets/source/browse/#svn%2Ftrunk%2FDoubleSlider%2Fsrc%2Fdouble_slider