gridbaglayouttest.java

编程之道--java程序设计入门源代码

/**
 * 网格组布局管理器测试
 */

import java.awt.Container;
import java.awt.BorderLayout;
import java.awt.GridBagLayout;
import java.awt.Component;
import java.awt.GridBagConstraints;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JComboBox;
import javax.swing.JTextArea;
import javax.swing.BoxLayout;

public class GridBagLayoutTest
{
    public static void main(String[] args)
    {  
        GridBagLayoutFrame frame = new GridBagLayoutFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.show();
    }
}

class GridBagLayoutFrame extends JFrame
{  
    private static final int WIDTH = 300;
    private static final int HEIGHT = 200;  
    
    public GridBagLayoutFrame()
    {  
        setTitle("学生信息输入界面");
        setSize(WIDTH, HEIGHT);

        Container con = getContentPane();
        con.add(new StudentJPanel(), BorderLayout.CENTER);
        con.add(new ButtonPanel(), BorderLayout.SOUTH);
    }
}

class StudentJPanel extends JPanel
{
    public StudentJPanel()
    {
        GridBagLayout layout = new GridBagLayout();
        setLayout(layout);
        
        //构造并添加组件
        JLabel nameLabel = new JLabel("姓名: ");
        JTextField nameTextField = new JTextField(10);

        JLabel numberLabel = new JLabel("学号: ");
        JTextField numberTextField = new JTextField(10);
        
        JLabel sexLabel = new JLabel("性别: ");
        JComboBox sexComboBox = new JComboBox(new String[]{"男", "女"});
  
        JLabel addressLabel = new JLabel("籍贯: ");
        JComboBox addressCombo = new JComboBox(new String[]
            {"山东", "河南", "北京", "黑龙江", "河北"});
 
        JLabel commentLabel = new JLabel("简 单 介 绍");
        JTextArea sample = new JTextArea();
        sample.setLineWrap(true);       

        // 添加到网格组布局中
        GridBagConstraints constraints = new GridBagConstraints();

        constraints.fill = GridBagConstraints.NONE;
        constraints.anchor = GridBagConstraints.EAST;
        constraints.weightx = 5;
        constraints.weighty = 5;

        add(nameLabel, constraints, 0, 0, 1, 1);
        add(numberLabel, constraints, 0, 1, 1, 1);
        add(sexLabel, constraints, 0, 2, 1, 1);
        add(addressLabel, constraints, 0, 3, 1, 1);

        constraints.fill = GridBagConstraints.HORIZONTAL;
        constraints.weightx = 100;
        
        add(nameTextField, constraints, 1, 0, 1, 1);
        add(numberTextField, constraints, 1, 1, 1, 1);
        add(sexComboBox, constraints, 1, 2, 1, 1);
        add(addressCombo, constraints, 1, 3, 1, 1);
        
        constraints.fill = GridBagConstraints.NONE;
        constraints.anchor = GridBagConstraints.CENTER;
        add(commentLabel, constraints, 2, 0, 1, 1);
        
        constraints.fill = GridBagConstraints.BOTH;
        add(sample, constraints, 2, 1, 1, 3);
    }
  
    
    public void add(Component c, GridBagConstraints constraints,
        int x, int y, int w, int h)
    {  
        constraints.gridx = x;
        constraints.gridy = y;
        constraints.gridwidth = w;
        constraints.gridheight = h;
        add(c, constraints);
    }
}

class ButtonPanel extends JPanel
{
    public ButtonPanel()
    {
        setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
        JButton okButton = new JButton("确定");
        JButton cancelButton = new JButton("取消");
        
        Box hbox = Box.createHorizontalBox();
        hbox.add(Box.createHorizontalStrut(40));        
        hbox.add(okButton);
        //在两个按钮间添加一个水平弹簧
        hbox.add(Box.createHorizontalGlue());
        hbox.add(cancelButton);
        hbox.add(Box.createHorizontalStrut(40));
        
        add(hbox);
    }
}