1计算器 Java 编程代码1、界面截图1、程序代码import java.awt.*;import java.awt.event.*;import javax.swing.*;public class Counter implements ActionListener / 改进小数问题private boolean append = false;JButton jb = new JButton20;JTextField jtf = new JTextField(19);String st = Backs, CE, C, +, 7 , 8 , 9, -, 4 , 5 , 6, *, 1 , 2 , 3, /, . , +/-, 0, =, ;String num1 = 0;String operator = +;public Counter() JFrame jf = new JFrame(计算器);/ 界面设置GridLayout gl = new GridLayout(6, 1);jf.setLayout(gl);JPanel jp0 = new JPanel();2jp0.add(jtf);jf.add(jp0);JPanel jp1 = new JPanel();for (int i = 0; i 0) jtf.setText(temp.substring(0, temp.length() - 1);public static void main(String args) new Counter();