[ JAVA ] GUI기반 계산기 프로그램 만들기

계산기 프로그램 만들기

 

프로그램 GUI

 

 

 

전체 코드

import java.awt.*;
import javax.swing.*;
import java.util.*;
import java.awt.event.*;

public class Cal extends JFrame implements ActionListener{
	JButton b1, b2, b3, b4, b5, b6, b7, b8, b9, b10;
	JButton b11, b12, b13, b14, b15, b16, b17;
	JTextField tf;
	Vector<String> v;
	
	Cal(){
		super("계산기");
		
		v=new Vector<String>(5);
		v.add("0");v.add("0");v.add("0");v.add("0");v.add("T");
		
		tf=new JTextField("0", 20);
		tf.setHorizontalAlignment(JTextField.RIGHT);
		tf.setSelectionStart(1);
		b1=new JButton("1");		b1.addActionListener(this);
		b2=new JButton("2");		b2.addActionListener(this);
		b3=new JButton("3");		b3.addActionListener(this);
		b4=new JButton("4");		b4.addActionListener(this);
		b5=new JButton("5");		b5.addActionListener(this);
		b6=new JButton("6"); 		b6.addActionListener(this);
		b7=new JButton("7");		b7.addActionListener(this);
		b8=new JButton("8");		b8.addActionListener(this);
		b9=new JButton("9");  		b9.addActionListener(this);
		b10=new JButton("0");		b10.addActionListener(this);
		
		b11=new JButton("C");		b11.addActionListener(new C());
		b12=new JButton(".");		b12.addActionListener(this);
		
		b13=new JButton("+");		b13.addActionListener(new OP());
		b14=new JButton("-");		b14.addActionListener(new OP());
		b15=new JButton("*");		b15.addActionListener(new OP());
		b16=new JButton("/");		b16.addActionListener(new OP());
		b17=new JButton("=");		b17.addActionListener(new Re());
		
		JPanel p1 = new JPanel();
		p1.setLayout(new GridLayout(4, 4));
		p1.add(b1);		p1.add(b2);		p1.add(b3);		p1.add(b4);		p1.add(b5);		
		p1.add(b6);		p1.add(b7);		p1.add(b8);		p1.add(b9);		
		p1.add(b10);	p1.add(b11);	p1.add(b12);	p1.add(b13);	p1.add(b14);	
		p1.add(b15);	p1.add(b16);	p1.add(b17);
		this.add("North", tf);
		this.add("Center", p1);
		this.add("South", b17);
		
		this.setDefaultCloseOperation(3);
		this.setSize(300, 300);
		this.setVisible(true);
	}
	
	public static void main(String[] args) {
		new Cal();
	}

	@Override
	public void actionPerformed(ActionEvent arg0) {
		JButton jj=(JButton)arg0.getSource();
		String st=jj.getText();	//1234567
		String flag=v.get(4);	//T F
		String old=tf.getText();
		
		if(flag.equals("T")) {
			   if(!(old.equals("0")&st.equals("0"))) {
				  if(st.equals(".")) {
					  tf.setText("0.");
					  v.set(4,"F");
				  } else {
			         tf.setText(st);
			         v.set(4,"F");
				  }
			   }		  
		 }else {//F		
			 if(!(st.equals(".")&old.contains("."))){
			    old=old+st;
			    tf.setText(old);	
			 }
		 }
	} //action

	class C implements ActionListener{
		@Override
		public void actionPerformed(ActionEvent e) {
			tf.setText("0");
			v.set(0,"0");v.set(1,"0");v.set(2,"0");v.set(3,"0");
			v.set(4,"T");
			System.out.println(v);
		}
	}//C class
	
	class OP implements ActionListener{
		@Override
		public void actionPerformed(ActionEvent arg0) {
			JButton jj=(JButton)arg0.getSource();
			String st=jj.getText();	//+-*
			String n1=tf.getText();	//12
			v.set(0, n1); v.set(1, st); v.set(4, "T");
			System.out.println("연산 : "+v);
		}
	}//OP
	
	class Re implements ActionListener{
		@Override
		public void actionPerformed(ActionEvent e) {
			String n2=tf.getText();	//3
			v.set(2, n2);
			v.set(4, "T");	//[12,+,3,0,T])
			String n1=v.get(0);	//12
			double num1=Double.parseDouble(n1);	//12.0
			double num2=Double.parseDouble(n2);	//3.0
			double sum=0.0;
			String op=v.get(1);	//*-+/
			if(op.equals("+")) sum=num1+num2;
			else if(op.equals("-")) sum=num1-num2;
			else if(op.equals("*")) sum=num1*num2;
			else if(op.equals("/")){	//나눗셈
				System.out.println(num2);
				if(num2==0.0) {
					tf.setText("0으로 나눌 수 없음");
					return;
				}
				else sum=num1/num2;
			}
			
			String sum2=""+sum;
			String r[]=sum2.split("\\.");	//[12,0]
			if(r[1].equals("0"))
				tf.setText(r[0]);
			else
				tf.setText(sum2);
			
			v.set(3, sum2);
			System.out.println("최종"+v);
		}//action
	}//Re
	
}//Cal class