Question

所以我正在设计一个GUI（GUI本身在称为mainGUI的单独类中）。 GUI有2个按钮，每个按钮将main.subProgramNumber设置为1或2（取决于按钮），将main.safeToContinue设置为false，然后使用dispose（）处置GUI。但是当我单击GUI中的按钮时，GUI关闭，然后什么也没有发生。我已经使用了调试器，奇怪的是，使用调试工具时，代码的行为有所不同。使用调试工具时，单击该按钮后GUI仍保持打开状态并永久加载。任何帮助都将受到欢迎。

 genData main = new genData();
 main.safeToContinue = false;
 main.running = true;

 while(main.running == true){

        //trigger GUI    
        mainGUI MG = new mainGUI();
        MG.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        MG.setSize(250, 275);
        MG.setVisible(true);

        //wait tell the GUI says its safe to continue
        while(main.safeToContinue == false){
            try {
                TimeUnit.MILLISECONDS.sleep(1);
            } catch (InterruptedException ex) {
                Logger.getLogger(mainGUI.class.getName()).log(Level.SEVERE, null, ex);
            }
        }

        //check if main.subProgram is 1
        if(main.subProgramNumber == 1){
            System.out.println("subProgram = 1");
        }

        //check if main.subProgram is 2
        if(main.subProgramNumber == 2){
           System.out.println("subProgram = 2");
        }


}

下面的

是我的GUI代码的简化版本。（抱歉，它的代码很多，但我想不出如何使它比这更简单...）

public class mainGUI extends JFrame{

    public JButton add;
    public JButton remove;
    public JButton edit;
    public JButton report;
    public JButton close;

    public mainGUI(){
        super("Guest Manager");
        setLayout(new FlowLayout());

        add = new JButton("Add a Guest");
        remove = new JButton("Remove a Guest");
        close = new JButton("Close");

        add(add);
        add(remove);
        add(close);

        addGuest ag = new addGuest();
        add.addActionListener(ag);

        removeGuest rg = new removeGuest();
        remove.addActionListener(rg);

        Close c = new Close();
        close.addActionListener(c);

    }

    private class addGuest implements ActionListener{

        public void actionPerformed(ActionEvent e){
            genData main = new genData();
            main.subProgramNumber = 1; 
            main.safeToContinue = true;
            dispose();
        }
    }

    private class removeGuest implements ActionListener{

        public void actionPerformed(ActionEvent e){
            genData main = new genData();
            main.subProgramNumber = 2;  
            main.safeToContinue = true;
            dispose();
        }
    }

    private class Close implements ActionListener{

        public void actionPerformed(ActionEvent e){

            genData main = new genData();
            main.safeToContinue = true;
            dispose();
        }
    }
}

下面是我所使用（并且正在上面使用）的一种请求的，唤醒的示例

主程序（当我单击“开始”时称为该程序）：

 varData MC = new varData();
        do{

            MC.safeToContinue = false;

            //open and run the main GUI
            ExerciseMainGUI EM = new ExerciseMainGUI();
            EM.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
            EM.setSize(250, 275);
            EM.setVisible(true);

            //System.out.println("debug 1");

            //wait tell the sub program closes to continue
            do{
                hutLib.pause(1);
            }while(MC.safeToContinue==false);

            hutLib.pause(1);

        }while(MC.running == true);

我在上面调用的GUI：

public class ExerciseMainGUI extends JFrame{

    private JButton bottlePacker;
    private JButton triangleTester;
    private JButton primeChecker;
    private JButton averager;
    private JButton rollTheDice;
    private JButton close;

    public ExerciseMainGUI(){
        super("Java Exercises");
        setLayout(new FlowLayout());

        bottlePacker = new JButton("   Bottle Packer   ");
        triangleTester = new JButton("  Triangle Tester  ");
        primeChecker = new JButton("   Prime Checker   ");
        averager = new JButton ("Averager (offline)");
        rollTheDice = new JButton("Roll the Dice (offline)");
        close = new JButton("       Close       ");

        add(bottlePacker);
        add(triangleTester);
        add(primeChecker);
        add(averager);
        add(rollTheDice);
        add(close);

        bottlePacker bp = new bottlePacker();
        bottlePacker.addActionListener(bp);

        triangleTester tt = new triangleTester();
        triangleTester.addActionListener(tt);

        primeChecker pc = new primeChecker();
        primeChecker.addActionListener(pc);

        averager a = new averager();
        averager.addActionListener(a);

        rollTheDice rtd = new rollTheDice();
        rollTheDice.addActionListener(rtd);

        close c = new close();
        close.addActionListener(c);
    }

    private class bottlePacker implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            //runs a subprogram

        }
    }

    private class triangleTester implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            //runs a subprogram
        }
    }

    private class primeChecker implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            //runs a subprogram

        }
    }

    private class averager implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            //runs a subprogram

        }
    }

    private class rollTheDice implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            //runs a subprogram

            //JOptionPane.showMessageDialog(null, "NOTE: Roll the Dice will run in the command line.");

            //oldCodeStorage.rollTheDice.rollTheDice();

        }
    }

    private class close implements ActionListener{

        public void actionPerformed(ActionEvent e){
            dispose();
            varData MC = new varData();
            MC.running = false;
            MC.safeToContinue = true;

        }
    }
}

注意：每个子程序完成后，运行以下代码：

varData MC = new varData();
MC.safeToContinue = true;

我知道很多东西，但是我被明确要求张贴。

Answer 1

您在这里滥用了Swing组件。您应该显示您的应用并通过事件监听器对事件做出反应。这不需要循环等。

例如

public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setLayout(new GridLayout(1, 2));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


        JButton b1 = new JButton("Action 1");
        JButton b2 = new JButton("Action 2");
        b1.addActionListener((e)->System.out.println("Action 1 taken")); // your subcommand 1 
        b2.addActionListener((e)->System.out.println("Action 2 taken")); //your subcomand 2
        frame.add(b1);
        frame.add(b2);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

还请记住不要在actionListeners中调用昂贵的操作，而要将它们委派给后台作业-否则它将冻结UI。用Swing编写UI应用程序并不像您想象的那样简单，并且需要少量的基础知识（关于Swing本身）。尝试也不错，但是如果不熟悉Swing的基础知识，您将遭受不胜枚举的麻烦-相信我，我去过那里。

您已经提到过，Thing是陌生的-Swing本身是单线程的-但它涉及线程来执行各种任务，这些任务会使应用程序变慢或使其无响应。

我强烈建议您开始研究Oracle Swing教程。

https://docs.oracle.com/javase/tutorial/uiswing/index.html

Answer 2

您根本没有修改main.safeToContinue。这就是为什么它陷入无限的while循环

Answer 3

我们说我们有一堂课。

class GenData{
    static int x = 0;
    int y = 1;
}

现在我有该对象的两个实例。

GenData a = new GenData();
GenData b = new GenData();

a.x = 5;
a.y = 10;

System.out.println( b.x + ", " + b.y );

您期望输出是什么？

b有它自己的实例变量。所以我希望输出是。

5，1

在您的代码中，调用new genData()来创建该类的新实例。如果您的字段不是静态的，则不会与您正在检查的genData版本共享。

也请使用Java命名约定。 GenData更适合用作类名。

如何修复。

public class mainGUI extends JFrame{

    public JButton add;
    public JButton remove;
    public JButton edit;
    public JButton report;
    public JButton close;
    genData main;
    public mainGUI(genData main){
        this.main = main;
        //don't change the rest.
    }

    private class addGuest implements ActionListener{

        public void actionPerformed(ActionEvent e){
            //genData main = new genData();
            //don't call new here, use the reference you 
            //received.
        }
    }

}

GUI程序卡住了

3 个答案: