JAVA Swing으로 만든 사칙연산 간단 계산기

콘솔로 만든 후에 지난 학기에 배웠던 swing으로 해보면 어떨까 싶었다.

복습할 겸 좋을 것 같아서 만들어보았다.

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swing으로 만든 간단 사칙연산 계산기

package project_1;

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

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class SwingMain {
	JFrame frame;
	JPanel panel;
	JLabel result;
	String total = null;
	// 전역변수 초기화 
	int a = -1;
	int b = -1;
	int CalCase = 0;
	boolean count;
	
	public void Layout() {
		frame = new JFrame();
		panel = new JPanel();
		JButton btn_num1 = new JButton("1");
		JButton btn_num2 = new JButton("2");
		JButton btn_num3 = new JButton("3");
		JButton btn_num4 = new JButton("4");
		JButton btn_num5 = new JButton("5");
		JButton btn_num6 = new JButton("6");
		JButton btn_num7 = new JButton("7");
		JButton btn_num8 = new JButton("8");
		JButton btn_num9 = new JButton("9");
		JButton btn_num0 = new JButton("0");

		JButton btn_plus = new JButton("+");
		JButton btn_minus = new JButton("-");
		JButton btn_mul = new JButton("*");
		JButton btn_div = new JButton("/");
		
		JButton btn_equal = new JButton("=");
		
		JButton btn_reset = new JButton("ac");
		
		
		result = new JLabel("0", JLabel.RIGHT);
		
		panel.setLayout(null);
		
		// panel에 요소들 추가
		panel.add(result);
		panel.add(btn_plus);
		panel.add(btn_minus);
		panel.add(btn_mul);
		panel.add(btn_div);
		panel.add(btn_num1);
		panel.add(btn_num2);
		panel.add(btn_num3);
		panel.add(btn_num4);
		panel.add(btn_num5);
		panel.add(btn_num6);
		panel.add(btn_num7);
		panel.add(btn_num8);
		panel.add(btn_num9);
		panel.add(btn_num0);
		panel.add(btn_equal);
		panel.add(btn_reset);
		
		// 각 요소 레이아웃에 배치
		result.setBounds(50, 50, 230, 50);
		btn_plus.setBounds(50, 110, 50, 50);
		btn_minus.setBounds(110, 110, 50, 50);
		btn_mul.setBounds(170, 110, 50, 50);
		btn_div.setBounds(230, 110, 50, 50);
		btn_num1.setBounds(50, 170, 50, 50);
		btn_num2.setBounds(110, 170, 50, 50);
		btn_num3.setBounds(170, 170, 50, 50);
		btn_num4.setBounds(50, 230, 50, 50);
		btn_num5.setBounds(110, 230, 50, 50);
		btn_num6.setBounds(170, 230, 50, 50);
		btn_num7.setBounds(50, 290, 50, 50);
		btn_num8.setBounds(110, 290, 50, 50);
		btn_num9.setBounds(170, 290, 50, 50);
		btn_num0.setBounds(50, 350, 170, 50);
		btn_equal.setBounds(230, 170, 50, 110);
		btn_reset.setBounds(230, 290, 50, 110);
		
		// 이벤트 발생
		btn_num1.addActionListener(new Calculate());
		btn_num2.addActionListener(new Calculate());
		btn_num3.addActionListener(new Calculate());
		btn_num4.addActionListener(new Calculate());
		btn_num5.addActionListener(new Calculate());
		btn_num6.addActionListener(new Calculate());
		btn_num7.addActionListener(new Calculate());
		btn_num8.addActionListener(new Calculate());
		btn_num9.addActionListener(new Calculate());
		btn_num0.addActionListener(new Calculate());
		
		btn_plus.addActionListener(new Arithmetic());
		btn_minus.addActionListener(new Arithmetic());
		btn_mul.addActionListener(new Arithmetic());
		btn_div.addActionListener(new Arithmetic());
		
		btn_equal.addActionListener(new Equal());
		btn_reset.addActionListener(new AllClear());
		
		frame.add(panel);
		
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setSize(350, 500);
		frame.setVisible(true);
	}
	public static void main(String[] args) {
		SwingMain SwingCal = new SwingMain();
		SwingCal.Layout();
		
	}
	
	class Calculate implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			JButton btn = (JButton)e.getSource();
			if(count==false) {
				if(btn.getText().equals("1"))
					a = 1;
				else if(btn.getText().equals("2"))
					a = 2;
				else if(btn.getText().equals("3"))
					a = 3;
				else if(btn.getText().equals("4"))
					a = 4;
				else if(btn.getText().equals("5"))
					a = 5;
				else if(btn.getText().equals("6"))
					a = 6;
				else if(btn.getText().equals("7"))
					a = 7;
				else if(btn.getText().equals("8"))
					a = 8;
				else if(btn.getText().equals("9"))
					a = 9;
				else if(btn.getText().equals("0"))
					a = 0;
			}
			else if(count==true) {
				if(btn.getText().equals("1"))
					b = 1;
				else if(btn.getText().equals("2"))
					b = 2;
				else if(btn.getText().equals("3"))
					b = 3;
				else if(btn.getText().equals("4"))
					b = 4;
				else if(btn.getText().equals("5"))
					b = 5;
				else if(btn.getText().equals("6"))
					b = 6;
				else if(btn.getText().equals("7"))
					b = 7;
				else if(btn.getText().equals("8"))
					b = 8;
				else if(btn.getText().equals("9"))
					b = 9;
				else if(btn.getText().equals("0"))
					b = 0;
			}
		}
	}
	class Arithmetic implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			JButton btn = (JButton)e.getSource();
			count = true;
			if(btn.getText().equals("+"))
				CalCase = 1;
			else if(btn.getText().equals("-"))
				CalCase = 2;
			else if(btn.getText().equals("*"))
				CalCase = 3;
			else if(btn.getText().equals("/"))
				CalCase = 4;
		}
	}
	
	class Equal implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			if(CalCase==1) {
				total = Integer.toString(a+b);
			}
			else if(CalCase==2) {
				total = Integer.toString(a-b);
			}
			else if(CalCase==3) {
				total = Integer.toString(a*b);
			}
			else if(CalCase==4) {
				total = Integer.toString(a/b);
			}
			result.setText(total);
		}
	}
	class AllClear implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			a = -1;
			b = -1;
			CalCase = 0;
			total = null;
			result.setText("0");
			count = false;
		}
	}
}

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보완해야 할 것

1. 배열을 이용해서 하면 좋을 것 같다.

2. JLabel 칸이 보이도록한다.

3. 다양한 기능 추가해보기 -> 공학용 계산기처럼

4. 이전에 계산했던 내용 저장 -> 다시 볼 수 있도록

5. 결과값에 계속해서 연산 가능하게