ScrollBar

In JavaFX, a ScrollBar is a control that allows users to scroll through content either vertically or horizontally. It’s different from ScrollPane because ScrollPane automatically handles scrolling for content, while ScrollBar is a standalone control you can use to manually track or control values.

Example: Simple ScrollBar

FXML (hello-view.fxml)

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.ScrollBar?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.VBox?>

<VBox spacing="10" alignment="CENTER"
      xmlns="http://javafx.com/javafx/17"
      xmlns:fx="http://javafx.com/fxml/1"
      fx:controller="org.example.demo.HelloController">

    <Label fx:id="valueLabel" text="Scroll Value: 0"/>
    <ScrollBar fx:id="scrollBar" min="0" max="100" unitIncrement="1"/>
</VBox>

Controller (HelloController.java)

package org.example.demo;

import javafx.fxml.FXML;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollBar;

public class HelloController {

    @FXML
    private ScrollBar scrollBar;

    @FXML
    private Label valueLabel;

    @FXML
    public void initialize() {
        // Listen for changes in the ScrollBar
        scrollBar.valueProperty().addListener((obs, oldVal, newVal) -> {
            valueLabel.setText("Scroll Value: " + newVal.intValue());
        });
    }
}

Key Points:

1. Orientation: By default, ScrollBar is vertical. You can make it horizontal:

   <ScrollBar orientation="HORIZONTAL" ... />
   

2. Properties:

   • min – Minimum value
   • max – Maximum value
   • value – Current value
   • unitIncrement – Amount to scroll with arrow buttons
   • blockIncrement – Amount to scroll when clicking on the track

3. You can bind ScrollBar to control content manually or use it to show progress in custom components.