java小程序计算3个数相加!帮忙看一下!

Question

我在JComboBox里加了3个元素!在JTextField里输入值后,点按钮"计算".计算出3个数相加的值!在JTextField里显示出来!请会的帮忙继续写一下!给50分!
界面代码:
import javax.swing.*;
public class Class7 extends JFrame {
private JPanel jPanel1 = new JPanel();
private JComboBox jbox = new JComboBox();
private JTextField jTextField1 = new JTextField(5);
private JButton jButton1 = new JButton();

public Class7() {
try {
jbInit();
} catch (Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
Class7 class7 = new Class7();
class7.setSize(300,200);
class7.setVisible(true);
class7.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

private void jbInit() throws Exception {
jButton1.setText("计算");
jPanel1.add(jbox, null);
jPanel1.add(jTextField1, null);
jPanel1.add(jButton1, null);
this.getContentPane().add(jPanel1, null);
jbox.addItem("第1个数");
jbox.addItem("第2个数");
jbox.addItem("第3个数");

}
}

Answer 1

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

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Class7 extends JFrame {
private JPanel jPanel1 = new JPanel();
private JComboBox jbox = new JComboBox();
private JTextField jTextField1 = new JTextField(5);
private JButton jButton1 = new JButton();
private JButton jButton2 = new JButton();
int s1;
int s2;
int s3;
public Class7() {
try {
jbInit();
} catch (Exception e) {
e.printStackTrace();
}

jButton2.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e) {
if(jTextField1.isEditable()){
int i=jbox.getSelectedIndex();
if(i==0)
if(jTextField1.getText()!=null&&!"".equals(jTextField1.getText().trim()))
s1=Integer.parseInt(jTextField1.getText().trim());
if(i==1)
if(jTextField1.getText()!=null&&!"".equals(jTextField1.getText().trim()))
s2=Integer.parseInt(jTextField1.getText().trim());
if(i==2)
if(jTextField1.getText()!=null&&!"".equals(jTextField1.getText().trim()))
s3=Integer.parseInt(jTextField1.getText().trim());
System.out.println("s1=="+s1+":s2=="+s2+":s3=="+s3);
}

}

});
jButton1.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e) {
jTextField1.setText((s1+s2+s3)+"");

}

});
}

public static void main(String[] args) {
Class7 class7 = new Class7();
class7.setSize(300,200);
class7.setVisible(true);
class7.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

private void jbInit() throws Exception {
jButton1.setText("计算");
jButton2.setText("付值");
jPanel1.add(jbox, null);
jPanel1.add(jTextField1, null);
jPanel1.add(jButton2, null);
jPanel1.add(jButton1, null);

this.getContentPane().add(jPanel1, null);
jbox.addItem("第1个数");
jbox.addItem("第2个数");
jbox.addItem("第3个数");

}
}

不明白的给我留言吧