Split String从文本文件中读取，传入ArrayList，然后显示在JComboBox-JavaSwing中

Question

我试图从文本文件中提取某些单词，并将它们显示在JComboBox中。我试图使用SplitString（）方法，但它似乎不起作用。

目前文本文件是这样的。

课程代码-课程描述-考官-主持人

我试图分裂它，所以JComboBox只会显示：

课程代码-课程描述

这是我正在使用的代码（请原谅混乱和缺乏最佳实践，我是新手，正在努力学习）。

package messingwithswing;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
import javax.swing.border.EmptyBorder;


public class ReportGUI extends JFrame{
    //Fields
    private JButton viewAllReports = new JButton("View All Program Details");
    private JButton viewPrograms = new JButton("View Programs and Majors Associated with this course"); 
    private JButton viewTaughtCourses = new JButton("View Courses this Examiner Teaches"); 
    private JLabel courseLabel = new JLabel("Select a Course: ");
    private JLabel examinerLabel = new JLabel("Select an Examiner: "); 
    private JPanel panel = new JPanel(new GridLayout(6,2,4,4));  
    private ArrayList<String> nameList = new ArrayList<String>(); 
    private ArrayList<String> courseList = new ArrayList<String>();  


     public ReportGUI(){   
            reportInterface();
            allReportsBtn();     
            examinnerFileRead();
           // courseFileRead();
            comboBoxes();
     }        

     private void examinnerFileRead(){
         try{
             Scanner scan = new Scanner(new File("Course.txt"));

             while(scan.hasNextLine()){
                 String getname = scan.nextLine();
                 String[] names = getname.split("-");
                 courseList.add(scan.nextLine());
                 String name = names[0];
                 String course = names[1];    

             }
             scan.close();
         }
         catch (FileNotFoundException e){
             e.printStackTrace();
         }
     }
//      private void courseFileRead(){
//         try{
//             Scanner scan = new Scanner(new File("Course.txt"));
//            
//             while(scan.hasNextLine()){
//                 courseList.add(scan.nextLine());
//             }
//             scan.close();
//         }
//         catch (FileNotFoundException e){
//             e.printStackTrace();
//         }
//     }

    private void reportInterface(){         
          setTitle("Choose Report Specifications");                   
          setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
          JPanel panel = new JPanel(new FlowLayout());        
          add(panel, BorderLayout.CENTER);
          setSize(650,200);
          setVisible(true);    
          setResizable(false);
          setLocationRelativeTo(null);
}    
    private void allReportsBtn(){
        JPanel panel = new JPanel(new GridLayout(1,1)); 
        panel.setBorder(new EmptyBorder(70, 50, 70, 25));
        panel.add(viewAllReports);        
        viewAllReports.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e){               
                new AllDataGUI();
            }
        });         
        add(panel, BorderLayout.LINE_END);
    }       
    private void comboBoxes(){                
        panel.setBorder(new EmptyBorder(0, 5, 5, 10));
        String[] comboBox1Array = nameList.toArray(new String[nameList.size()]);
        JComboBox comboBox1 = new JComboBox(comboBox1Array);          
        panel.add(examinerLabel);
        panel.add(comboBox1);          
        panel.add(viewTaughtCourses);
         viewTaughtCourses.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {                 
                 new ViewCourseGUI();
            }
        });  
         String[] comboBox2Array = courseList.toArray(new String[courseList.size()]);
         JComboBox comboBox2 = new JComboBox(comboBox2Array);
         panel.add(courseLabel);         
         panel.add(comboBox2); 
         panel.add(viewPrograms);
         viewPrograms.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {                 
                 new ViewProgramGUI();             
            }
        });  
         add(panel, BorderLayout.LINE_START); 

    }   

}

如果您不想深入研究上述混乱情况，使用split方法的代码是：

 private void examinnerFileRead(){
         try{
             Scanner scan = new Scanner(new File("Course.txt"));

             while(scan.hasNextLine()){
                 String getname = scan.nextLine();
                 String[] names = getname.split("-");
                 courseList.add(scan.nextLine());
                 String name = names[0];
                 String course = names[1];    

             }
             scan.close();
         }
         catch (FileNotFoundException e){
             e.printStackTrace();
         }
     }

组合框代码为：

 private void comboBoxes(){                
        panel.setBorder(new EmptyBorder(0, 5, 5, 10));
        String[] comboBox1Array = nameList.toArray(new String[nameList.size()]);
        JComboBox comboBox1 = new JComboBox(comboBox1Array);          
        panel.add(examinerLabel);
        panel.add(comboBox1);          
        panel.add(viewTaughtCourses);
         viewTaughtCourses.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {                 
                 new ViewCourseGUI();
            }
        });  
         String[] comboBox2Array = courseList.toArray(new String[courseList.size()]);
         JComboBox comboBox2 = new JComboBox(comboBox2Array);
         panel.add(courseLabel);         
         panel.add(comboBox2); 
         panel.add(viewPrograms);
         viewPrograms.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {                 
                 new ViewProgramGUI();             
            }
        });  
         add(panel, BorderLayout.LINE_START); 

    }  

Answer 1

以下片段有几个问题：

         while(scan.hasNextLine()){
             String getname = scan.nextLine();
             String[] names = getname.split("-");
             courseList.add(scan.nextLine());
             String name = names[0];
             String course = names[1];    

         }

>

当第一行进入本地数组names并且第二行被添加到courseList时，您正在一次循环迭代中读取两行。

名称，名称和课程都是局部变量，在它们声明的方法之外不可见。

Answer 2

我猜测哪些令牌属于每个列表，但你需要这样的东西：

         while(scan.hasNextLine()){
             String line = scan.nextLine();
             String[] tokens = line.split("-");
             String code = tokens[0].trim();
             String description = tokens[1].trim();
             String examiner = tokens[2].trim();
             String moderator = tokens[3].trim();

             courseList.add(code);
             courseList.add(description);

             nameList.add(examiner);
             nameList.add(moderator);
         }