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copied!<p>Here is an answer based on earlier sample code from: <a href="https://stackoverflow.com/questions/18892070/javafx-2-2-hooking-slider-drag-n-drop-events">JavaFX 2.2: Hooking Slider Drag n Drop Events</a>.</p> <p><img src="https://i.stack.imgur.com/tWUiv.png" alt="slider value change logger"></p> <p>The sample extends <a href="http://docs.oracle.com/javafx/2/api/javafx/scene/control/Slider.html" rel="nofollow noreferrer">Slider</a> with a <code>FunctionalSlider</code> class that takes a <a href="http://download.java.net/jdk8/docs/api/java/util/function/DoubleFunction.html" rel="nofollow noreferrer">DoubleFunction</a> as an argument. Applications of the <code>DoubleFunction</code> create custom tick labels using a slider <a href="http://docs.oracle.com/javafx/2/api/javafx/scene/control/Slider.html#setLabelFormatter%28javafx.util.StringConverter%29" rel="nofollow noreferrer">labelFormatter</a>. The <code>DoubleFunction</code> also supplies values to a <code>functionValue</code> property which represents the value of the function evaluated at a given tick mark. The code uses <a href="https://jdk8.java.net/download.html" rel="nofollow noreferrer">Java 8</a>.</p> <pre><code>import javafx.application.Application; import javafx.beans.property.*; import javafx.geometry.*; import javafx.scene.Scene; import javafx.scene.control.*; import javafx.scene.layout.*; import javafx.stage.Stage; import javafx.util.StringConverter; import java.util.function.DoubleFunction; class FunctionalSlider extends Slider { private ReadOnlyDoubleWrapper functionValue = new ReadOnlyDoubleWrapper(); public FunctionalSlider(DoubleFunction<Double> function) { valueProperty().addListener(observable -> functionValue.set( function.apply(getValue()) ) ); setLabelFormatter(new StringConverter<Double>() { @Override public String toString(Double x) { return String.format( "%1$.0f", function.apply(x) ); } @Override public Double fromString(String s) { return null; } }); } public double getFunctionValue() { return functionValue.get(); } public ReadOnlyDoubleProperty functionValueProperty() { return functionValue.getReadOnlyProperty(); } } public class FunctionalSliderSample extends Application { private final ListView<String> startLog = new ListView<>(); private final ListView<String> endLog = new ListView<>(); @Override public void start(Stage stage) throws Exception { Pane logsPane = createLogsPane(); Slider slider = createMonitoredSlider(); VBox layout = new VBox(10); layout.setAlignment(Pos.CENTER); layout.setPadding(new Insets(10)); layout.getChildren().setAll( slider, logsPane ); VBox.setVgrow(logsPane, Priority.ALWAYS); stage.setTitle("Slider Value Change Logger"); stage.setScene(new Scene(layout)); stage.show(); } private Slider createMonitoredSlider() { final FunctionalSlider slider = new FunctionalSlider( x -> Math.pow(2, x) ); slider.setMin(0); slider.setValue(1); slider.setMax(5); slider.setMajorTickUnit(1); slider.setMinorTickCount(0); slider.setShowTickMarks(true); slider.setShowTickLabels(true); slider.setSnapToTicks(true); slider.setMinHeight(Slider.USE_PREF_SIZE); slider.valueChangingProperty().addListener(observable -> { slider.setValue(Math.round(slider.getValue())); String valueString = String.format( "%1$.2f", slider.getFunctionValue() ); if (slider.valueChangingProperty().get()) { startLog.getItems().add( valueString ); } else { endLog.getItems().add( valueString ); } }); return slider; } private HBox createLogsPane() { HBox logs = new HBox(10); logs.getChildren().addAll( createLabeledLog("Start", startLog), createLabeledLog("End", endLog) ); return logs; } public Pane createLabeledLog(String logName, ListView<String> log) { Label label = new Label(logName); label.setLabelFor(log); VBox logPane = new VBox(5); logPane.getChildren().setAll( label, log ); logPane.setAlignment(Pos.TOP_LEFT); return logPane; } public static void main(String[] args) { launch(args); } } </code></pre>

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