按钮布局演示

package yyww;
import java.awt.*;
import javax.swing.*;
public class LayoutTextextendsJFrame extends JFrame { //创建类LayoutText继承于类JFrame
JButton btn1,btn2,btn3,btn4,btn5;
JPanel mainPan;
FlowLayout fLayout; //定义布局方式
GridLayout gLayout;
BorderLayout bLayout;
CardLayout cLayout;
public LayoutTextextendsJFrame(String layoutstyle) { //定义构造函数
super(“布局方式：”+layoutstyle);
mainPan=new JPanel();
fLayout=new FlowLayout(FlowLayout.LEFT); //创建4种布局方式的对象
gLayout=new GridLayout(3,2);
bLayout=new BorderLayout();
cLayout=new CardLayout(10,10);
if(layoutstyle==”fLayout”) //判断采用何种布局方式
mainPan.setLayout(fLayout);
else if(layoutstyle==”gLayout”)
mainPan.setLayout(gLayout);
else if(layoutstyle==”bLayout”)
mainPan.setLayout(bLayout);
else if(layoutstyle==”cLayout”)
mainPan.setLayout(cLayout);
else
System.out.print(“布局方式输入错误!”);
getContentPane().add(mainPan);
btn1=new JButton(“按钮1”); //创建5个按钮类的对象
btn2=new JButton(“按钮2”);
btn3=new JButton(“按钮2”);
btn4=new JButton(“按钮4”);
btn5=new JButton(“按钮5”);
if(layoutstyle==”fLayout”||layoutstyle==”gLayout”); //定义fLayoutg或Layout的布局方式
{
mainPan.add(btn1);
mainPan.add(btn2);
mainPan.add(btn3);
mainPan.add(btn4);
mainPan.add(btn5);
}
if(layoutstyle==”bLayout”||layoutstyle==”cLayout”);//定义bLayoutg或cLayout的布局方式
{
mainPan.add(btn1,”East”);
mainPan.add(btn2,”South”);
mainPan.add(btn3,”West”);
mainPan.add(btn4,”North”);
mainPan.add(BorderLayout.CENTER,btn5);
}
setSize(250,150); //设置界面宽度和高度
setVisible(true); //设置界面的可见性
setDefaultCloseOperation(EXIT_ON_CLOSE); //设置窗口关闭时的默认操作
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new LayoutTextextendsJFrame(“fLayout”);
new LayoutTextextendsJFrame(“gLayout”);
new LayoutTextextendsJFrame(“bLayout”);
new LayoutTextextendsJFrame(“cLayout”);
}
}