BorderLayout布局，修改各个区域大小办法

摘自http://blog.csdn.net/zcsearching/article/details/50808446

BorderLayout控件大小的设置

使用BorderLayout时，中间的面板会随着窗体的变化而变化，其他区域的大小根据添加组件多少而变化。举个例子，现在想将一个面板固定到上边，高度为固定值，这是我们需要设置面板的高度。但是调用面板的 setSize()方法根本没有效果。调用 setMaximumSize()和setMinimumSize()都没有用。

最后才发现应该调用的是 setPreferredSize()才能达到效果。

请看栗子。

 

---

 package com.wst.bj;

 import java.awt.BorderLayout;
 import java.awt.Dimension;
 import java.awt.Toolkit;

 import javax.swing.JButton;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import javax.swing.JTextArea;
 import javax.swing.JTextField;

 public class LayoutDemo {

     public static void main(String[] args) {
         new myFrame();
     }
 }

 /**
  * @author liuyan
  *
  */
 class myFrame {

     JFrame jframe = new JFrame("搜索");
     JTextField textField = new JTextField(20);
     JButton jButton = new JButton("转到");
     JButton jButton2 = new JButton("转到2");
     JButton jButton3 = new JButton("转到3");
     JButton jButton4 = new JButton("转到4");
     JTextArea textArea = new JTextArea();
     JPanel jPanel = new JPanel(new BorderLayout(5,20));
     JPanel jPanel2 = new JPanel(new BorderLayout());
     JPanel jPanel3 = new JPanel(new BorderLayout());
     JPanel jPanel4 = new JPanel(new BorderLayout());

     /**
      *
      */
     public myFrame() {

         init();
     }

     /**
      *
      */
     private void init()
     {
         jframe.setLayout(new BorderLayout());
         jframe.add(jPanel2, BorderLayout.SOUTH);
         jframe.add(jPanel3, BorderLayout.EAST);
         jframe.add(jPanel4, BorderLayout.WEST);
         jframe.add(jPanel, BorderLayout.NORTH);

         jPanel.add(jButton, BorderLayout.EAST);
         jPanel.add(textField, BorderLayout.CENTER);

         jPanel2.add(jButton2);
         jPanel3.add(jButton3);
         jPanel4.add(jButton4);

         jPanel.setPreferredSize(new Dimension(0, 150));
         jPanel2.setPreferredSize(new Dimension(0, 150));
         jPanel3.setPreferredSize(new Dimension(150, 0));
         jPanel4.setPreferredSize(new Dimension(150, 0));

         jframe.add(textArea, BorderLayout.CENTER);

         jframe.setVisible(true);
         FrameUtil.initFram(jframe, 500, 700);
     }
 }

 class FrameUtil
 {
     public static void  initFram(JFrame f, int width, int height)
     {
         Toolkit toolkit = Toolkit.getDefaultToolkit();
         f.setVisible(true);
         f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         Dimension d = toolkit.getScreenSize();
         int x = (int)d.getWidth();
         int y = (int)d.getHeight();
         f.setBounds((x-width)/2, (y - height )/2, width, height);
     }
 }

---

 package com.wst.bj;

 import java.awt.BorderLayout;
 import java.awt.Dimension;
 import java.awt.Toolkit;

 import javax.swing.JButton;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import javax.swing.JTextArea;
 import javax.swing.JTextField;

 public class LayoutDemo {

     public static void main(String[] args) {
         new myFrame();
     }
 }

 /**
  * @author liuyan
  *
  */
 class myFrame {

     JFrame jframe = new JFrame("搜索");
     JTextField textField = new JTextField(20);
     JButton jButton = new JButton("转到");
     JButton jButton2 = new JButton("转到2");
     JButton jButton3 = new JButton("转到3");
     JButton jButton4 = new JButton("转到4");
     JTextArea textArea = new JTextArea();
     JPanel jPanel = new JPanel(new BorderLayout(5,20));
     JPanel jPanel2 = new JPanel(new BorderLayout());
     JPanel jPanel3 = new JPanel(new BorderLayout());
     JPanel jPanel4 = new JPanel(new BorderLayout());

     /**
      *
      */
     public myFrame() {

         init();
     }

     /**
      *
      */
     private void init()
     {
         jframe.setLayout(new BorderLayout());
         jframe.add(jPanel2, BorderLayout.SOUTH);
         jframe.add(jPanel3, BorderLayout.EAST);
         jframe.add(jPanel4, BorderLayout.WEST);
         jframe.add(jPanel, BorderLayout.NORTH);

         jPanel.add(jButton, BorderLayout.EAST);
         jPanel.add(textField, BorderLayout.CENTER);

         jPanel2.add(jButton2);
         jPanel3.add(jButton3);
         jPanel4.add(jButton4);

 //        jPanel.setPreferredSize(new Dimension(0, 150));
 //        jPanel2.setPreferredSize(new Dimension(0, 150));
 //        jPanel3.setPreferredSize(new Dimension(150, 0));
 //        jPanel4.setPreferredSize(new Dimension(150, 0));

         jframe.add(textArea, BorderLayout.CENTER);

         jframe.setVisible(true);
         FrameUtil.initFram(jframe, 500, 700);
     }
 }

 class FrameUtil
 {
     public static void  initFram(JFrame f, int width, int height)
     {
         Toolkit toolkit = Toolkit.getDefaultToolkit();
         f.setVisible(true);
         f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         Dimension d = toolkit.getScreenSize();
         int x = (int)d.getWidth();
         int y = (int)d.getHeight();
         f.setBounds((x-width)/2, (y - height )/2, width, height);
     }
 }