Swing - JScrollBar 类

介绍

JScrollBar 类是滚动条的实现。

类声明

以下是javax.swing.JScrollBar类的声明：

public class JScrollBar
   extends JComponent
      implements Adjustable, Accessible

字段

以下是javax.swing.ImageIcon类的字段：

• protected int blockIncrement

• protected BoundedRangeModel model - 表示滚动条的最小值、最大值、范围（也称为“visibleAmount”）和当前值的模型。

• protected int orientation

• protected int unitIncrement

类构造函数

类方法

继承的方法

此类继承自以下类的方法：

• java.lang.Object

JScrollBar 示例

使用您选择的任何编辑器创建以下 Java 程序，例如在D:/ > SWING > com > tutorialspoint > gui >中。

SwingControlDemo.java

package com.tutorialspoint.gui;
 
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
public class SwingControlDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;

   public SwingControlDemo(){
      prepareGUI();
   }
   public static void main(String[] args){
      SwingControlDemo  swingControlDemo = new SwingControlDemo();      
      swingControlDemo.showScrollbarDemo();
   }
   private void prepareGUI(){
      mainFrame = new JFrame("Java Swing Examples");
      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 showScrollbarDemo() {                                       
      headerLabel.setText("Control in action: JScrollbar"); 

      final JScrollBar horizontalScroller = new JScrollBar(JScrollBar.HORIZONTAL);
      final JScrollBar verticalScroller = new JScrollBar();
      verticalScroller.setOrientation(JScrollBar.VERTICAL);
      horizontalScroller.setMaximum (100);
      horizontalScroller.setMinimum (1);
      verticalScroller.setMaximum (100);
      verticalScroller.setMinimum (1);
      
      horizontalScroller.addAdjustmentListener(new AdjustmentListener() {
         @Override
         public void adjustmentValueChanged(AdjustmentEvent e) {
            statusLabel.setText("Horozontal: "
               +horizontalScroller.getValue() 
               +" ,Vertical: "
               + verticalScroller.getValue());
            }
      });
      verticalScroller.addAdjustmentListener(new AdjustmentListener() {
         @Override
         public void adjustmentValueChanged(AdjustmentEvent e) {
            statusLabel.setText("Horozontal: "
               +horizontalScroller.getValue() 
               +" ,Vertical: "+ verticalScroller.getValue());
         }
      });
      controlPanel.add(horizontalScroller);
      controlPanel.add(verticalScroller);
      
      mainFrame.setVisible(true);  
   } 
}

使用命令提示符编译程序。转到D:/ > SWING并键入以下命令。

D:\SWING>javac com\tutorialspoint\gui\SwingControlDemo.java

如果未出现错误，则表示编译成功。使用以下命令运行程序。

D:\SWING>java com.tutorialspoint.gui.SwingControlDemo

验证以下输出。