我认为有问题的代码已经加粗,望大神解惑
package com.google;
import java.awt.FlowLayout;
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.JTextField;
public class enhen {
public static void main(String[] args) {
// TODO Auto-generated method stub
MYJFrame ks=new MYJFrame();
}
}
class MYJFrame extends JFrame implements ActionListener{
JLabel jl1,jl2,jl3;
JTextField jtf1,jtf2;
JButton jb1,jb2;
//构造方法
public MYJFrame() {
//创建组件
jl1=new JLabel("输入数据");
jl2=new JLabel("→");
jl3=new JLabel("结果");
jtf1=new JTextField(10);
jtf2=new JTextField(10);
jb1=new JButton("判断");
//监听器
jb1.addActionListener(this);
jb2=new JButton("重置");
jb2.addActionListener(this);
//布局管理器
this.setLayout(new FlowLayout(FlowLayout.CENTER));
//添加组件
this.add(jl1);
this.add(jtf1 );
this.add(jl2);
this.add(jl3);
this.add(jtf2);
this.add(jb1);
this.add(jb2);
//设置属性
this.setVisible(true);
this.setLocation(500,300);
this.setSize(600,100);
this.setTitle("判断质数");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setResizable(false);
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getActionCommand().equals("转换")) {
int i;
float a;
String b;
a=Float.parseFloat(jtf1.getText());
//
if(a<=0) {
b="输入错误";
}else {
for(i = 2; i < a; i++) {
if(a%i==0)
break;
}
if(i==a) {
b="是质数";
}else
b="不是质数";
}
****jtf2.setText(b);****
}else if(e.getActionCommand().equals("重置")) {
jtf1.setText(null);
jtf2.setText(null);
}
}
}