calculatedemo.java

来自「java课件 java课件 java课件 java课件」· Java 代码 · 共 69 行

// CalculateDemo.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CalculateDemo extends JFrame implements ActionListener{
	private JTextField jtfNum1,jtfNum2,jtfResult;
	private JButton jbtAdd,jbtSub,jbtMul,jbtDiv;
	public CalculateDemo(){
	  setTitle("Calculate Demo");
	  JPanel p1 = new JPanel();
	  p1.setLayout(new FlowLayout());
	  p1.add(new JLabel("Number1"));
	  p1.add(jtfNum1=new JTextField(5));
	  p1.add(new JLabel("Number2"));
	  p1.add(jtfNum2=new JTextField(5));
	  p1.add(new JLabel("Result"));
	  p1.add(jtfResult=new JTextField(8));
	  jtfResult.setEditable(false);
	  
	  JPanel p2 = new JPanel();
	  p2.setLayout(new FlowLayout());
	  p2.add(jbtAdd=new JButton("Add"));
	  p2.add(jbtSub=new JButton("Subtract"));
	  p2.add(jbtMul=new JButton("Multiply"));
	  p2.add(jbtDiv=new JButton("Divide"));
	  
	  getContentPane().setLayout(new BorderLayout());
	  getContentPane().add(p1,BorderLayout.CENTER);
	  getContentPane().add(p2,BorderLayout.SOUTH);
	  
	  jbtAdd.addActionListener(this);
	  jbtSub.addActionListener(this);
	  jbtMul.addActionListener(this);
	  jbtDiv.addActionListener(this);
	  
	  pack();
	  setVisible(true);
	  setResizable(false);
	  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
	}
	
	public void actionPerformed(ActionEvent e){
	  String command = e.getActionCommand();
	  if(command.equals("Add"))
	     calculate('+');
	  else if(command.equals("Subtract"))   	
	  	 calculate('-');
	  else if(command.equals("Multiply"))   	
	  	 calculate('*');
	  else if(command.equals("Divide"))   	
	  	 calculate('/');
	}
	private void calculate(char operator){
		int num1 = Integer.parseInt(jtfNum1.getText().trim());
		int num2 = Integer.parseInt(jtfNum2.getText().trim());
		int result = 0;
		switch(operator){
		   case '+':result=num1+num2;break;	
		   case '-':result=num1-num2;break;
		   case '*':result=num1*num2;break;
		   case '/':result=num1/num2;break;
		}
		jtfResult.setText(String.valueOf(result));
	}
	public static void main(String[]args){
		new CalculateDemo();
	}
}