第七次实训

package 第七次实训;

import java.awt.*;

import javax.swing.*;

public class 计算器 {
    JFrame f;
    JPanel p;
    JButton[] b;
    JTextField t;
    String title[]= {"7","8","9","/","4","5","6","*","1","2","3","-","0",".","=","+"};
    GridLayout q1;
    public 计算器() {
        f=new JFrame("计算机");
        p=new JPanel();
        b=new JButton[16];
        t=new JTextField(10);
        for(int i=0;i<16;i++) {
            b[i]=new JButton(title[i]);
            p.add(b[i]);
        }
        //已设置完循环
        q1=new GridLayout(4,4);
        p.setLayout(q1);
        f.add(t,BorderLayout.NORTH);
        f.add(p,BorderLayout.CENTER);
        f.setVisible(true);
        f.setSize(400,300);
    }
    public static void main(String args[]) {
        new 计算器();
    }
    

}

package 第七次实训;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.*;

public class 改变窗口颜色 implements ActionListener {//创建接口
    JFrame f;
    JPanel p1,p2;
    JButton b1,b2,b3;
    public 改变窗口颜色() {
        f=new JFrame("点击按钮改变背景颜色");
        p1=new JPanel();
        p2=new JPanel();
        b1=new JButton("绿色");
        b1.addActionListener(this);//加监听
        b2=new JButton("蓝色");
        b2.addActionListener(this);//加监听
        b3=new JButton("灰色");
        b3.addActionListener(this);//加监听
        p2.setBackground(Color.pink);        
        p1.add(b1);
        p1.add(b2);
        p1.add(b3);
        f.add(p1,BorderLayout.NORTH);
        f.add(p2,BorderLayout.CENTER);
        f.setSize(400,300);
        f.setVisible(true);
    }
    public static void main(String args[]) {
        new 改变窗口颜色();
    }
    @Override
    public void actionPerformed(ActionEvent e) {
        // TODO 自动生成的方法存根
       if(e.getSource()==b1) {
           p2.setBackground(Color.green);
       }
       else if(e.getSource()==b2) {
           p2.setBackground(Color.cyan);
       }
       else if(e.getSource()==b3) {
           p2.setBackground(Color.darkGray);
       }
    }
    
    

}