java - 计算器项目问题

Question

好的，我在使用这个计算器时遇到了问题。我被分配了项目，我只会使用加法和减法。作业的第一部分是使用 Scanner 类创建它。所以我创建了一个循环，计算器工作了……但是乘法和除法关闭了。它基本上只是不断添加数字...比如 3*6 答案将是 24...但是我做 2 * 1 它会是 26 之类的东西。哦是的我将类保存为不同的文件.. ..有人可以帮我吗

在这里

public class Calculator_part2 extends calculator_gui{

public static void main(String[]args)
{
 calculator_gui n = new calculator_gui();
 n.gui();
}
}

import javax.swing.*;
import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;





public class calculator_gui implements ActionListener
{
 JFrame frame = new JFrame(" Calculator " );
 JPanel panel = new JPanel(new FlowLayout());

 JTextArea text = new JTextArea(1,20);
 JButton but1 = new JButton("1");
 JButton but2 = new JButton("2");
 JButton but3 = new JButton("3");
 JButton but4 = new JButton("4");
 JButton but5 = new JButton("5");
 JButton but6 = new JButton("6");
 JButton but7 = new JButton("7");
 JButton but8 = new JButton("8");
 JButton but9 = new JButton("9");
 JButton but0 = new JButton("0");

 JButton add = new JButton( " + ");
 JButton sub = new JButton( " - ");
 JButton multi = new JButton (" * ");
 JButton div = new JButton("/");
 JButton buteq = new JButton (" = ");

 JButton butclear = new JButton("C");

 Double number1,number2,result = 0.0,temp = 0.0;
 int addc = 0, subc=0,multic=0,divc=0,i = 0;

 public void gui()
 {
  frame.setVisible(true);
  frame.setSize(250,200);
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

  frame.add(panel);

  panel.add(text);
  panel.add(but1);
  panel.add(but2);
  panel.add(but3);
  panel.add(but4);
  panel.add(but5);
  panel.add(but6);
  panel.add(but7);
  panel.add(but8);
  panel.add(but9);
  panel.add(but0);

  panel.add(add);
  panel.add(sub);
  panel.add(multi);
  panel.add(div);
  panel.add(buteq);
  panel.add(butclear);

  but1.addActionListener(this);
  but2.addActionListener(this);
  but3.addActionListener(this);
  but4.addActionListener(this);
  but5.addActionListener(this);
  but6.addActionListener(this);
  but7.addActionListener(this);
  but8.addActionListener(this);
  but9.addActionListener(this);
  but0.addActionListener(this);
  add.addActionListener(this);
  sub.addActionListener(this);
  multi.addActionListener(this);
  div.addActionListener(this);
  buteq.addActionListener(this);
  butclear.addActionListener(this);


}

public void actionPerformed(ActionEvent e)
{
 Object source = e.getSource();

 if(source == butclear)
 {
  //number1 = 0.0;
  //number2 = 0.0;
  text.setText("");
 }

 if(source == but1)
 {
  text.append("1");
}

 if(source == but2)
 {
  text.append("2");
}

 if(source == but3)
 {
  text.append("3");
}

 if(source == but4)
 {
  text.append("4");
}

 if(source == but5)
 {
  text.append("5");
}

 if(source == but6)
 {
  text.append("6");
}

 if(source == but7)
 {
  text.append("7");
}

 if(source == but8)
 {
  text.append("8");
}

 if(source == but9)
 {
  text.append("9");
}

 if(source == but0)
 {
  text.append("0");
}
if(source == add)
{
 number1 = number_reader();
 text.setText("");
 addc=1;
 subc=0;
 multic=0;
 divc=0;
}
if(source == sub)
{
 number1 = number_reader();
 text.setText("");
 addc=0;
 subc=1;
 multic=0;
 divc=0;
}
if(source == multi)
{
 number1 = number_reader();
 text.setText("");
 addc=0;
 subc=0;
 multic=1;
 divc=0;
}
if(source == div)
{
 number1 = number_reader();
 text.setText("");
 addc=0;
 subc=0;
 multic=0;
 divc=1;
}

if(source == buteq)
{
 number2 = number_reader();
 if(addc>0)
 {
  result = number1 + number2;
  text.setText(Double.toString(result));
 }
 if(subc>0)
  {
   result = number1 - number2;
   text.setText(Double.toString(result));
 }
 if(multic>0)
  {

   for(  double i = 0;i <number2;i++)
     {
      result += number1;
     }


   text.setText(Double.toString(result));
 }
 if(divc>0)
  {
   for (i = 0; temp < number1; i++)
     {
     temp += number2;
     }

   text.setText(Double.toString(i));
 }
}
}

public double number_reader()
{
 double num1;
 String s;
 s = text.getText();
 num1 = Double.valueOf(s);

 return num1;

}
}

Answer 1

您需要在 performAction 的底部将结果重置为 0.0。此外，您的除法实现将 i 设置为文本。那绝对是不对的。