简单计算器
public class Example9_8 {
public static void main(String[] args) {
WindowOperation win =new WindowOperation();
win.setBounds(100,100,390,360);
win.setTitle("简单计算");
}
}
import java.awt.*;
import javax.swing.*;
import java.io.*;
public class WindowOperation extends JFrame{
JTextField inputNumberOne,inputNumberTwo;
JComboBox choiceFuhao;
JTextArea textShow;
JButton button;
OperatorListener operator;
ComputerListener computer;
public WindowOperation() {
init();
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
void init() {
setLayout(new FlowLayout());
inputNumberOne = new JTextField(5);
inputNumberTwo = new JTextField(5);
choiceFuhao = new JComboBox();
button = new JButton("计算");
choiceFuhao.addItem("选择运算符号");
String [] a = {"+","-","*","/"};
for(int i=0;i<a.length;i++) {
choiceFuhao.addItem(a[i]);
}
textShow = new JTextArea(9,30);
operator = new OperatorListener();
computer = new ComputerListener();
operator.setJComboBox(choiceFuhao);
operator.setWorkTogether(computer);
computer.setJTextFieldOne(inputNumberOne);
computer.setJTextFieldOne(inputNumberTwo);
computer.setJTextArea(textShow);
choiceFuhao.addItemListener(operator);
button.addActionListener(computer);
add(inputNumberOne);
add(choiceFuhao);
add(inputNumberTwo);
add(button);
add(new JScrollPane(textShow));
}
}
import java.awt.event.*;
import javax.swing.*;
public class OperatorListener implements ItemListener {
JComboBox choice;
ComputerListener workTogether;
public void setJComboBox(JComboBox box) {
choice = box;
}
public void setWorkTogether(ComputerListener computer) {
workTogether = computer;
}
public void itemStateChanged(ItemEvent e) {
String fuhao = choice.getSelectedItem().toString();
workTogether.setFuhao(fuhao);
}
}
import java.awt.event.*;
import javax.swing.*;
public class ComputerListener implements ActionListener{
JTextField inputNumberOne,inputNumberTwo;
JTextArea textShow;
String fuhao;
public void setJTextFieldOne(JTextField t) {
inputNumberOne = t;
}
public void setJTextFieldTwo(JTextField t) {
inputNumberTwo = t;
}
public void setJTextArea(JTextArea area) {
textShow = area;
}
public void setFuhao(String s) {
fuhao = s;
}
public void actionPerformed(ActionEvent e) {
try {
double number1 = Double.parseDouble(inputNumberOne.getText());
double number2 = Double.parseDouble(inputNumberTwo.getText());
double result = 0;
if(fuhao.equals("+")) {
result = number1+number2;
}
else if(fuhao.equals("-")) {
result = number1-number2;
}
else if(fuhao.equals("*")) {
result = number1*number2;
}
else if(fuhao.equals("/")) {
result = number1/number2;
}
textShow.append(number1+" "+fuhao+" "+number2+" = "+result+"\n");
}
catch(Exception exp) {
textShow.append("\n请输入数字字符\n");
}
}
}
