GridLayout的類層次結構圖：
java.lang.Object
--java.awt.GridLayout
GridLayout比FlowLayout多了行和列的設置，也就是說妳要先設置GridLayout***有幾行
幾列，就如同二維平面壹般，然後妳加
進去的組件會先填第壹行的格子，然後再從第二行開始填，依此類扒，就像是壹個個的
格子壹般。而且GridLayout會將所填進去組
件的大小設為壹樣。
構造函數：GridLayout()建立壹個新的GridLayout，默認值是1行1列。
GridLayout(int rows,int
cols)建立壹個幾行幾列的GridLayout.
GridLayout(int rows,int cols, int hgap,int
vgap)建立壹個幾行幾列的GridLayout,並設置組件的間距。
例子：GridLayoutDemo.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CardLayoutDemo implements ActionListener{
JPanel p1,p2,p3,p4;
int i=1;
JFrame f;
public CardLayoutDemo(){
f=new JFrame();//當做top-level組件
Container contentPane=f.getContentPane();
contentPane.setLayout(new GridLayout(2,1));
p1=new JPanel();
Button b=new Button("Change Card");
b.addActionListener(this);//當按下"Change
Card"時，進行事件監聽，將會有系統操作產生。
p1.add(b); file://處理操作在52-64行.
contentPane.add(p1);
p2=new JPanel();
p2.setLayout(new FlowLayout());
p2.add(new JButton("first"));
p2.add(new JButton("second"));
p2.add(new JButton("third"));
p3=new JPanel();
p3.setLayout(new GridLayout(3,1));
p3.add(new JButton("fourth"));
p3.add(new JButton("fifth"));
p3.add(new JButton("This is the last button"));
p4=new JPanel();
p4.setLayout(new CardLayout());
p4.add("one",p2);
p4.add("two",p3);
/*要顯示CardLayout的卡片，除了用show(Container parent,String
name)這個方法外
*，也可試試first(Container),next(Container),previous(Container),last
(Container)這
*四個方法，壹樣可以達到顯示效果。
*/
((CardLayout)p4.getLayout()).show(p4,"one");
contentPane.add(p4);
f.setTitle("CardLayout");
f.pack();
f.setVisible(true);
f.addWindowListener(
new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
}
);
}
public void actionPerformed(ActionEvent event){
switch(i){
case 1:
((CardLayout)p4.getLayout()).show(p4,"two");
break;
case 2:
((CardLayout)p4.getLayout()).show(p4,"one");
break;
}
i++;
if (i==3) i=1;
f.validate();
}
public static void main(String[] args){
new CardLayoutDemo();
}
}
1-3-5:GridBagLayout的使用：是java中最有彈性但也是最復雜的壹種版面管理器。它
只有壹種構造函數，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()建立壹個新的GridBagLayout管理器。
GridBagConstraints()建立壹個新的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)建立壹個新的GridBagConstraints對象
，並指定其參數的值。
參數說明:
gridx,gridy:設置組件的位置，gridx設置為GridBagConstraints.RELATIVE代表此組件
位於之前所加入組件的右邊。
若將gridy設置為GridBagConstraints.RELATIVE代表此組件位於以前所加入組件的下
面。建議定義出
gridx,gridy的位置，以便以後維護程序。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。妳可以使
用GridBagConstraints.REMAINDER常
量，代表此組件為此行或此列的最後壹個組件，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:
當組件空間大於組件本身時，要將組件置於何處，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裏的各種設置都必須通過GridBagConstraints,因此當我
們將GridBagConstraints的參數都設置
好了之後，必須new壹個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();
}
}