java - 如果用户忘记在我的代码中选择 jRadioButton 如何停止执行？

Question

我的问题可能很简单，但无法解决它，我正在开发一个项目
我放置了 2 个单选按钮来选择性别； 如果用户忘记确定性别我如何打印错误消息来敦促用户
确定性别？这段代码开头的问题:

   private void jButton1ActionPerformed(ActionEvent evt) {                                         
    // TODO add your handling code here:
    String radioText="";
    if (jRadioButton1.isSelected()){radioText=jRadioButton1.getText();}
   //male   
    if (jRadioButton2.isSelected()){radioText=jRadioButton2.getText();} 
   // female      
    /*** want here if nothing selected:
     * JOptionPane.showMessageDialog(null,"you must determine gender!");
     * and exit the code
     */
   try
   {
    String first,second,last,operation;


    int bMonth,bDay,bYear; // to set birthDay
    int aMonth,aDay,aYear; //to set admissionDate
    int fileNo,weight,height;

    first = jTextField1.getText();
    second = jTextField2.getText();
    last = jTextField3.getText();
    operation=jTextField14.getText();
    bMonth = Integer.parseInt(jTextField4.getText());
    bDay = Integer.parseInt(jTextField5.getText());
    bYear = Integer.parseInt(jTextField6.getText());

    aMonth =Integer.parseInt(jTextField7.getText());
    aDay =Integer.parseInt(jTextField8.getText());
    aYear = Integer.parseInt(jTextField9.getText());
    fileNo=Integer.parseInt(jTextField10.getText());
    weight=Integer.parseInt(jTextField12.getText());
    height=Integer.parseInt(jTextField13.getText());

    Date birth = new Date( bMonth, bDay, bYear );
    Date admissionDate = new Date( aMonth, aDay,aYear );
    Patient patient = new Patient( first, second,last,fileNo      
    ,birth,admissionDate,weight,height,radioText,operation );

    patientsArray.add(patient);


       JOptionPane.showMessageDialog( null,patientsArray);
       }
     catch (NumberFormatException ex)
       {
       JOptionPane.showMessageDialog(null,"Input must be Integer!");
       }
     }                                        

Answer 1

您应该将 ButtonGroup 与单选按钮一起使用。这将允许您一次只能选择一个单选按钮。然后您可以检查 ButtonGroup 的选择。

JRadioButton male = new JRadioButton("Male");
JRadioButton female = new JRadioButton("Female");

ButtonGroup group = new ButtonGroup();
group.add(male);
group.add(female);

然后在 ActionListener 中您可以检查组:

if (group.getSelection() == null)
    // no selection has been made

您需要将 ButtonGroup 定义为实例变量，以便可以在 ActionListener 中引用它。

阅读 Swing 教程中关于 How to Use Radio Buttons 的部分了解更多信息和示例。