java 加法计算窗口 java实现加法计算器

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mob6454cc6553fc 2023-08-29 23:56:19

文章标签 java 加法计算窗口 swing java gui 特殊字符 文章分类 Java 后端开发

运用各种组件，设计一个简易（简陋）的加减法计算器
实验内容：做一个简易的加减法计算器（设计标准的计算器方法也差不多，多些按键和监听，这里给个简单的）
上效果图：

额，确实简陋了点，不过是纯手敲，不是用拖拽做的（感觉这样对这部分内容理解好一点）。
实现结果：
使得程序运行之后，当输入两个小数作为运算数后，点击“相加”或者“相减”按钮，两数相加或相减的结果就会显示在“运算结果”框中。如果点击“全部清零”按钮，那么两个运算数输入框和运算结果框中就会完全被清空。
上代码：
Test.java

public class Test {
    public static void main(String[] args) {
        new Calculator("简易计算器");
    }
}

布局
Calculator.java

import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.*;

public class Calculator extends JFrame {
    public Calculator(String title){
        super(title);
        Container container = this.getContentPane();
        //4个标签
        JLabel label1 = new JLabel("简易计算器");
        JLabel label2 = new JLabel("运算数一");
        JLabel label3 = new JLabel("运算数二");
        JLabel label4 = new JLabel("运算结果");

        //3个文本框
        JTextField num1 = new JTextField(10);//字符数
        JTextField num2 = new JTextField(10);//字符数
        JTextField num3 = new JTextField(20);//字符数

        //3个按钮
        JButton button1 = new JButton("相加");
        JButton button2 = new JButton("相减");
        JButton button3 = new JButton("全部清零");
        button3.setPreferredSize(new Dimension(100,30));

        //对应监听
        button1.addActionListener(new MyaddCalculatorListener(num1,num2,num3));
        button2.addActionListener(new MysubCalculatorListener(num1,num2,num3));
        button3.addActionListener(new MycleanCalculatorListener(num1,num2,num3));

        //布局
        container.setLayout(new FlowLayout());
        //四个个面板
        JPanel p1 = new JPanel();
        p1.setPreferredSize(new Dimension(300, 40));//强制面板大小
        p1.setBorder(new EmptyBorder(12,5,2,5));//改变面板边角,由于只能int，故p41直接控制大小
        JPanel p2 = new JPanel(new GridLayout(3,2,10,10));
        p2.setPreferredSize(new Dimension(180, 100));//太宽了，变小一点就可以减少距离
        JPanel p3 = new JPanel(new GridLayout(1,2,50,0));
        p3.setPreferredSize(new Dimension(180, 30));//强制面板大小
        JPanel p4 = new JPanel();


        p1.add(label1);
        p2.add(label2);
        p2.add(num1);
        p2.add(label3);
        p2.add(num2);
        p2.add(label4);
        p2.add(num3);
        p3.add(button1);
        p3.add(button2);
        p4.add(button3);

        container.add(p1);
        container.add(p2);
        container.add(p3);
        container.add(p4);

        setVisible(true);
        setBounds(100,100,300,360);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
}

监听实现功能
MyCalculatorListener.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.math.BigDecimal;

//监听器类
//相加
class MyaddCalculatorListener implements ActionListener {
    //获取变量
    private JTextField num1,num2,num3;

    public MyaddCalculatorListener(JTextField num1, JTextField num2, JTextField num3) {
        this.num1 = num1;
        this.num2 = num2;
        this.num3 = num3;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if(num1.getText().equals(null) || num1.getText().equals("") || num2.getText().equals(null) || num2.getText().equals("")){
            new MynullDialogDemo();//输入为空时有弹窗提示
            return;
        }
        if (new Mymethod().special(num1,num2)){
            return;
        }
        if(new Mydecimal().decimal(num1,num2)){
            return;
        }
        //1.获得两个数
        double n1 = Double.parseDouble(num1.getText());
        double n2 = Double.parseDouble(num2.getText());
        double sum1 = n1+n2;
        BigDecimal bg = new BigDecimal(sum1);//保留6位小数
        double f1 = bg.setScale(6, BigDecimal.ROUND_HALF_UP).doubleValue();
        //2.运算后放到第三个框
        num3.setText(""+f1);
    }
}
//相减
class MysubCalculatorListener implements ActionListener{
    //获取变量
    private JTextField num1,num2,num3;

    public MysubCalculatorListener(JTextField num1, JTextField num2, JTextField num3) {
        this.num1 = num1;
        this.num2 = num2;
        this.num3 = num3;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if(num1.getText().equals(null) || num1.getText().equals("") || num2.getText().equals(null) || num2.getText().equals("")){
            new MynullDialogDemo();
            return;
        }
        if (new Mymethod().special(num1,num2)){
            return;
        }
        if(new Mydecimal().decimal(num1,num2)){
            return;
        }
        //1.获得两个数
        double n1 = Double.parseDouble(num1.getText());
        double n2 = Double.parseDouble(num2.getText());
        double sum2 = n1-n2;
        BigDecimal bg = new BigDecimal(sum2);
        double f2 = bg.setScale(6, BigDecimal.ROUND_HALF_UP).doubleValue();
        //2.运算后放到第三个框
        num3.setText(""+f2);
    }
}

//清除
class MycleanCalculatorListener implements ActionListener{
    //获取变量
    private JTextField num1,num2,num3;

    public MycleanCalculatorListener(JTextField num1, JTextField num2, JTextField num3) {
        this.num1 = num1;
        this.num2 = num2;
        this.num3 = num3;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        num1.setText("");
        num2.setText("");
        num3.setText("");
    }
}

//弹窗的窗口(输入为空时)
class MynullDialogDemo extends JDialog{
    public MynullDialogDemo() {
        this.setVisible(true);
        this.setBounds(200,200,100,100);
        //this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container container = this.getContentPane();
        container.setLayout(null);
        JLabel label = new JLabel("运算数不能为空");
        label.setBounds(10,10,100,40);
        container.add(label);
    }
}

//弹窗的窗口(有特殊字符)
class MyspecialDialogDemo extends JDialog{
    public MyspecialDialogDemo() {
        this.setVisible(true);
        this.setBounds(200,200,200,100);
        Container container = this.getContentPane();
        container.setLayout(null);
        JLabel label = new JLabel("运算数不能含有特殊字符");
        label.setBounds(10,10,160,40);
        container.add(label);
    }
}

//弹窗的窗口(有特殊字符)
class MydecimalDialogDemo extends JDialog{
    public MydecimalDialogDemo() {
        this.setVisible(true);
        this.setBounds(200,200,200,100);
        Container container = this.getContentPane();
        container.setLayout(null);
        JLabel label = new JLabel("请核查运算数的小数点");
        label.setBounds(10,10,160,40);
        container.add(label);
    }
}

//检查是否有特殊字符
class Mymethod{
    public int qq = 0;
    public boolean special(JTextField num1, JTextField num2) {
        String str1 = num1.getText();
        String str2 = num2.getText();
        char[] a = str1.toCharArray();
        char[] b = str2.toCharArray();
        for(int i = 0; i<a.length; i++){
            if((a[i]>='0' && a[i]<='9') || a[i]=='.'){
                continue;
            }else {
                qq = 1;
                new MyspecialDialogDemo();
            }
        }
        for(int i = 0; i<b.length; i++){
            if((b[i]>='0' && b[i]<='9') || b[i]=='.'){
                continue;
            }else {
                qq = 1;
                new MyspecialDialogDemo();
            }
        }
        if(qq == 1){
            return true;
        }else {
            return false;
        }
    }
}
//检查小数点
class Mydecimal{
    public int flaga = 0;
    public int flagb = 0;
    public boolean decimal(JTextField num1, JTextField num2) {
        String str1 = num1.getText();
        String str2 = num2.getText();
        char[] a = str1.toCharArray();
        char[] b = str2.toCharArray();
        for(int i = 0; i<a.length; i++){
            if(a[0]=='.' || a[a.length-1]=='.'){
                new MydecimalDialogDemo();
                return true;
            }
            if(a[i]=='.'){
                flaga++;
            }
        }
        for(int i = 0; i<b.length; i++){
            if(b[0]=='.' || b[b.length-1]=='.'){
                new MydecimalDialogDemo();
                return true;
            }
            if(b[i]=='.'){
                flagb++;
            }
        }
        if(flaga > 1 || flagb >1){
            new MydecimalDialogDemo();
            return true;
        }else {
            return false;
        }
    }
}

效果图：

java 加法计算窗口 java实现加法计算器_java 加法计算窗口