java - 动态更新 JFrame 的问题

Question

我正在使用 NetNeans我有一个 JPanel，它应该显示一些已经输入的数据以及进度条，而程序的其余部分则执行一些冗长的处理(大约 1 分钟长)。处理完成后，同一个 JPanel 应该使用一些包含已处理数据的 JTextField 进行更新。问题:在处理过程中，JPanel 显示为完全空白。处理完成后，所有数据都会显示出来。这让我很困惑。这是我的编程方式:

    /*The parent class which calls the output JPanel
     *Lister is the output JPanel. The constructor calls initComponents(), and fills
     *text fields that contain the data that has already been input.
     *fillresult then triggers the processing function that takes a while. Once the
     *processing function is done, fillresult fills the processed data into the
     *respective Text Fields
     */
    ListWords = new Lister();
    System.out.println("l");
    ListWords.setVisible(true);
    ListWords.fillResult();

   //Lister constructor:
   Lister(){
         initComponents();
       MatchWords = new Matcher();//Matcher() only contains the initialization of a List

         jTextField1.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(0, 1));
         jTextField2.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(1, 2));
         jTextField3.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(2, 3));
         jTextField4.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(3, 4));
         jTextField5.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(4, 5));
         jTextField6.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(5, 6));
         jTextField7.setText(Scrabbulous.scrab.EntryWind.getCombo().substring(6));
   } 

   //fillresult():
 public void fillResult(){
    int rIndex = 0;
    MatchWords.makeWords(rIndex);
    while(MatchWords.realWords.Head == null && rIndex < 2){
        rIndex++;
        updateStatusBar();
        MatchWords.makeWords(rIndex);
    }
    Wordpoints = new String[MatchWords.realWords.getSize()];
    for(int i=0; i<Wordpoints.length; i++){
        Wordpoints[i] = "";
    }

    for(int i=0; i<MatchWords.realWords.getSize(); i++){
        int total = 0;
        for(int j=0; j<MatchWords.realWords.getNode(i).getWord().length(); j++){
            for(int k=0; k<Scrabbulous.scrab.scralphabet.length; k++){
                if(MatchWords.realWords.getNode(i).getWord().charAt(j) == Scrabbulous.scrab.scralphabet[k].getLetter()){
                    total += Scrabbulous.scrab.scralphabet[k].getValue();
                    Wordpoints[i] = ""+total;
                }
            }
        }
    }

    try{
        jTextField8.setText(MatchWords.realWords.Head.getWord());
        jTextField13.setText(Wordpoints[0]);
    }catch(NullPointerException e){
        jTextField8.setText("No Match Found");
        jTextField13.setText("-");
    }
    try{
        jTextField9.setText(MatchWords.realWords.getNode(1).getWord());
        jTextField14.setText(Wordpoints[1]);
    }catch(NullPointerException e){
        jTextField9.setText("No Match Found");
        jTextField14.setText("-");
    }
    try{
        jTextField10.setText(MatchWords.realWords.getNode(2).getWord());
        jTextField15.setText(Wordpoints[2]);
    }catch(NullPointerException e){
        jTextField10.setText("No Match Found");
        jTextField15.setText("-");
    }
    try{
        jTextField11.setText(MatchWords.realWords.getNode(3).getWord());
        jTextField16.setText(Wordpoints[3]);
    }catch(NullPointerException e){
        jTextField11.setText("No Match Found");
        jTextField16.setText("-");    
    }
    try{
        jTextField12.setText(MatchWords.realWords.getNode(4).getWord());
        jTextField17.setText(Wordpoints[4]);
    }catch(NullPointerException e){
        jTextField12.setText("No Match Found");
        jTextField17.setText("-");
    }

有人可以帮忙吗？哦，是的，我读到了有关添加 .refactor() 和/或 repaint() 的内容，但至少应该显示在构造函数中初始化的 jForms 吗？ :/另外，可能值得一提的是，当前 fillresult() 函数中的所有代码最初都在构造函数中，并且正在显示输出。但是，由于我想要此处的进度条，因此我已将其转移到新功能。请帮忙？

Answer 1

"The issue: The JPanel shows up completely blank throughout the time period the processing is going on. Once the processing is done, then all the data shows up."

所发生的情况是，所有事情都发生在一个线程上，即事件调度线程 (EDT)。为了发生事件，例如 JPanel 更新，需要完成之前的过程。

如 EDT 所述:

" Tasks on the event dispatch thread must finish quickly; if they don't, unhandled events back up and the user interface becomes unresponsive."

要解决此问题，您需要在后台线程中运行长进程。你应该看看Concurrency in Swing - 关于 Worker Threads and SwingWorker 的部分特别是。