是java中最有彈性但也是最復雜的一種版面管理器。它只有一種構造函數，但必須配合GridBagConstraints才能達到設置的效果。
GridBagLayout的類層次結構圖：
java.lang.Object
--java.awt.GridBagLayout
構造函數：
GirdBagLayout()建立一個新的GridBagLayout管理器。
GridBagConstraints()建立一個新的GridBagConstraints對象。
GridBagConstraints(int gridx,int gridy,int gridwidth,int gridheight,double weightx,double weighty,
int anchor,int fill, Insets insets,int ipadx,int ipady)建立一個新的GridBagConstraints對象
，并指定其參數的值。
參數說明:
gridx,gridy:設置組件的位置，gridx設置為GridBagConstraints.RELATIVE代表此組件位于之前所加入組件的右邊。
若將gridy設置為GridBagConstraints.RELATIVE代表此組件位于以前所加入組件的下面。建議定義出
gridx,gridy的位置，以便以后維護程序。表示放在幾行幾列，gridx=0,gridy=0時放在0行0列。
gridwidth,gridheight:用來設置組件所占的單位長度與高度，默認值皆為1。你可以使用GridBagConstraints.REMAINDER常
量，代表此組件為此行或此列的最后一個組件，而且會占據所有剩余的空間。
weightx,weighty:用來設置窗口變大時，各組件跟著變大的比例，當數字越大，表示組件能得到更多的空間，默認值皆為0。
anchor: 當組件空間大于組件本身時，要將組件置于何處，有CENTER(默認值)、NORTH、NORTHEAST、EAST、SOUTHEAST、
WEST、NORTHWEST可供選擇。
insets:設置組件之間彼此的間距，它有四個參數，分別是上，左，下，右，默認為(0,0,0,0).
ipadx,ipady:設置組件內的間距，默認值為0。
我們以前提過，GridBagLayout里的各種設置都必須通過GridBagConstraints,因此當我們將GridBagConstraints的參數都設置
好了之后，必須new一個GridBagConstraints的對象出來，以便GridBagLayout使用。
例子：
GridBagLayoutDemo.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GridBagLayoutDemo{
public GridBagLayoutDemo(){
JButton b;
GridBagConstraints c;
int gridx,gridy,gridwidth,gridheight,anchor,fill,ipadx,ipady;
double weightx,weighty;
Insets inset;
JFrame f=new JFrame();
GridBagLayout gridbag=new GridBagLayout();
Container contentPane=f.getContentPane();
contentPane.setLayout(gridbag);
b=new JButton("first");
gridx=0;
gridy=0;
gridwidth=1;
gridheight=1;
weightx=10;
weighty=1;
anchor=GridBagConstraints.CENTER;
fill=GridBagConstraints.HORIZONTAL;
inset=new Insets(0,0,0,0);
ipadx=0;
ipady=0;
c=new GridBagConstraints(gridx,gridy,gridwidth,gridheight,weightx,weighty,anchor,
fill,inset,ipadx,ipady);
gridbag.setConstraints(b,c);
contentPane.add(b);
b=new JButton("second");
gridx=1;
gridy=0;
gridwidth=2;
gridheight=1;
weightx=1;
weighty=1;
anchor=GridBagConstraints.CENTER;
fill=GridBagConstraints.HORIZONTAL;
inset=new Insets(0,0,0,0);
ipadx=50;
ipady=0;
c=new GridBagConstraints(gridx,gridy,gridwidth,gridheight,weightx,weighty,anchor,
fill,inset,ipadx,ipady);
gridbag.setConstraints(b,c);
contentPane.add(b);
b=new JButton("third");
gridx=0;
gridy=1;
gridwidth=1;
gridheight=1;
weightx=1;
weighty=1;
anchor=GridBagConstraints.CENTER;
fill=GridBagConstraints.HORIZONTAL;
inset=new Insets(0,0,0,0);
ipadx=0;
ipady=50;
c=new GridBagConstraints(gridx,gridy,gridwidth,gridheight,weightx,weighty,anchor,
fill,inset,ipadx,ipady);
gridbag.setConstraints(b,c);
contentPane.add(b);
b=new JButton("fourth");
gridx=1;
gridy=1;
gridwidth=1;
gridheight=1;
weightx=1;
weighty=1;
anchor=GridBagConstraints.CENTER;
fill=GridBagConstraints.HORIZONTAL;
inset=new Insets(0,0,0,0);
ipadx=0;
ipady=0;
c=new GridBagConstraints(gridx,gridy,gridwidth,gridheight,weightx,weighty,anchor,
fill,inset,ipadx,ipady);
gridbag.setConstraints(b,c);
contentPane.add(b);
b=new JButton("This is the last button");
gridx=2;
gridy=1;
gridwidth=1;
gridheight=2;
weightx=1;
weighty=1;
anchor=GridBagConstraints.CENTER;
fill=GridBagConstraints.HORIZONTAL;
inset=new Insets(0,0,0,0);
ipadx=0;
ipady=50;
c=new GridBagConstraints(gridx,gridy,gridwidth,gridheight,weightx,weighty,anchor,
fill,inset,ipadx,ipady);
gridbag.setConstraints(b,c);
contentPane.add(b);
f.setTitle("GridBagLayout");
f.pack();
f.setVisible(true);
f.addWindowListener(
new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
}
);
}
public static void main(String[] args){
new GridBagLayoutDemo();
}
}
原文參考自站長網：http://www.software8.co/wzjs/java/3475.html