Swing帶自定義標籤滾軸範例

下面的範例展示了如何在Java Swing應用程式中使用帶有自定義標籤的滾軸。

使用以下API -

• JSlider(orientation, min, max, value) - 在方向設定垂直方向時建立滾軸。
• JSlider.getValue() - 獲取滾軸的當前值。
• JSlider.setLabelTable() - 設定標籤。
• JSlider.setPaintLabels(true) - 顯示標籤。

範例

package com.yiibai.swingdemo;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.Hashtable;

public class SwingTester {
    private JFrame mainFrame;
    private JLabel headerLabel;
    private JLabel statusLabel;
    private JPanel controlPanel;

    public SwingTester() {
        prepareGUI();
    }

    public static void main(String[] args) {
        SwingTester swingControlDemo = new SwingTester();
        swingControlDemo.showSliderDemo();
    }

    private void prepareGUI() {
        mainFrame = new JFrame("Swing帶自定義標籤滾軸範例");
        mainFrame.setSize(400, 400);
        mainFrame.setLayout(new GridLayout(3, 1));

        mainFrame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent windowEvent) {
                System.exit(0);
            }
        });
        headerLabel = new JLabel("", JLabel.CENTER);
        statusLabel = new JLabel("", JLabel.CENTER);
        statusLabel.setSize(350, 100);

        controlPanel = new JPanel();
        controlPanel.setLayout(new FlowLayout());

        mainFrame.add(headerLabel);
        mainFrame.add(controlPanel);
        mainFrame.add(statusLabel);
        mainFrame.setVisible(true);
    }

    private void showSliderDemo() {
        headerLabel.setText("Control in action: JSlider");
        JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 10);
        Hashtable<Integer, JLabel> labelTable = new Hashtable<Integer, JLabel>();
        labelTable.put(new Integer(0), new JLabel("停止"));
        labelTable.put(new Integer(50), new JLabel("較慢"));
        labelTable.put(new Integer(100), new JLabel("較快"));
        slider.setLabelTable(labelTable);
        slider.setPaintLabels(true);
        slider.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent e) {
                statusLabel.setText("當前值 : " + ((JSlider) e.getSource()).getValue());
            }
        });
        controlPanel.add(slider);
        mainFrame.setVisible(true);
    }
}

執行上面範例程式碼，得到以下結果：