组合+内部类-简易计算器的编程代码-2022-12-8

改进前代码：

package com.lr.guifirstdemo;

import javax.xml.soap.Text;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class testTextDemo09  {
    public static void main(String[] args) {
        Calculator calculator = new Calculator();

    }
}


//计算器类
class Calculator extends Frame {
    public Calculator(){
        //3个文本框
        TextField num1 = new TextField(10);
        TextField num2 = new TextField(10);
        TextField num3 = new TextField(20);

        // 1个按钮
        Button button = new Button("=");
        button.addActionListener(new myCalculatorlistener(num1,num2,num3));

        //1个标签
        Label label = new Label("+");

        //布局
        setLayout(new FlowLayout());

        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);   
        
        pack();
        setVisible(true);
    }
}

//监听器类
class myCalculatorlistener implements ActionListener{

    private TextField num1,num2,num3;
    public myCalculatorlistener(TextField num1, TextField num2, TextField num3){
        this.num1 = num1;
        this.num2 = num2;
        this.num3 = num3;

    }

    @Override
    public void actionPerformed(ActionEvent e) {
        //1、获取加数和被加数
        int n1 = Integer.parseInt(num1.getText());
        int n2 = Integer.parseInt(num2.getText());
        //2、将计算后和的值放入第三个框
        num3.setText(""+(n1+n2));
        //3、清空第1，2个框
        num1.setText("");
        num2.setText("");
    }
}

改进为面向对象后：

package com.lr.guifirstdemo;

import javax.xml.soap.Text;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class testTextDemo09  {
    public static void main(String[] args) {
        new Calculator().loadFrame();

    }
}

//计算器类
class Calculator extends Frame {

    //属性
    TextField num1,num2,num3;

    //方法
    public void loadFrame(){
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(20);
        Button button = new Button("=");
        Label label = new Label("+");

        button.addActionListener(new myCalculatorlistener(this));

        //布局
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        pack();
        setVisible(true);
    }
}

//监听器类
class myCalculatorlistener implements ActionListener{

    // 获取计算器这个对象,在一个类中组合另一个类
    Calculator calculator = null ;
    //private TextField num1,num2,num3;
    public myCalculatorlistener(Calculator calculator){
        this.calculator=calculator;
    }

    @Override
    public void actionPerformed(ActionEvent e) {

        //1、获取加数和被加数
        int n1 = Integer.parseInt(calculator.num1.getText());
        int n2 = Integer.parseInt(calculator.num2.getText());

        //2、将计算后和的值放入第三个框
        calculator.num3.setText(""+(n1+n2));

        //3、清空第1，2个框
        calculator.num1.setText("");
        calculator.num2.setText("");

    }
}

内部类：

package com.lr.guifirstdemo;

import javax.xml.soap.Text;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class testTextDemo09  {
    public static void main(String[] args) {
        new Calculator().loadFrame();

    }
}

//计算器类
class Calculator extends Frame {

    //属性
    TextField num1,num2,num3;

    //方法
    public void loadFrame(){
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(20);
        Button button = new Button("=");
        Label label = new Label("+");

        button.addActionListener(new myCalculatorlistener());

        //布局
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        pack();
        setVisible(true);
    }

    //监听器类
  private  class myCalculatorlistener implements ActionListener{
        @Override
        public void actionPerformed(ActionEvent e) {

            //1、获取加数和被加数
            //2、将计算后和的值放入第三个框
            //3、清空第1，2个框
            int n1 = Integer.parseInt(num1.getText());
            int n2 = Integer.parseInt(num2.getText());
            num3.setText(""+(n1+n2));
            num1.setText("");
            num2.setText("");
        }
    }
}