Question

我有以下申请。它有效，我只是想更好地理解它所以从主要课程我做了以下调用

public static void main(String[] args) 
{
 Gui gui = new Gui();
 gui.startGui();    
}

在GUI类

中

public Gui() 
{   
 initialize();
}

private void initialize() 
{
 mainWinFrm = new JFrame();
 mainWinFrm.setTitle("Inventory Tool");

 JMenuBar menuBar = new JMenuBar();
 mainWinFrm.getContentPane().add(menuBar, BorderLayout.NORTH);
 .....//allot more GUI staff getting initialize
 }

public void startGui() 
{
  try {UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());} 
  catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {}
  EventQueue.invokeLater(new Runnable() 
  {
    public void run()
    {
      try 
      {
        Gui window = new Gui();
        window.mainWinFrm.setLocationRelativeTo(null);
        window.mainWinFrm.setMinimumSize(new Dimension(400, 200));
        window.mainWinFrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.mainWinFrm.pack();
        window.mainWinFrm.setVisible(true);             
       } 
    catch (Exception e) 
    {e.printStackTrace();} 
   }
 });
}

上面代码的结构是由GUI构建器构建的，我想我想了解发生了什么。

我不明白的主要观点是当我们在主类中构造对象 gui 时，它初始化所有变量，然后启动线程 gui.startGui（）该方法还会创建一个新的GUI对象窗口并初始化所有变量。

这对我来说似乎不对......但是我不确定我是否遗漏了某些东西。

感谢您的建议/帮助亚历

Answer 1

首先看一下Initial Threads

Gui课程有点尴尬......但距离可行不远......

在initialize中创建UI的基础知识，在startUI中切换到事件调度线程，创建Gui的新实例并显示主要内容帧...

奇怪的部分是在Gui中创建startUI的第二个实例。相反，你可以做一些像......

public Gui() 
{   
    // It's arguable, but I'm paranoid, so I prefer to do anything related
    // to the UI within the EDT...
}

private void initialize() 
{
    mainWinFrm = new JFrame();
    mainWinFrm.setTitle("Inventory Tool");

    JMenuBar menuBar = new JMenuBar();
    mainWinFrm.getContentPane().add(menuBar, BorderLayout.NORTH);
    .....//allot more GUI staff getting initialize
}

public void startGui() 
{
    try {UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());} 
    catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {}
    EventQueue.invokeLater(new Runnable() 
    {
        public void run()
        {
            try 
            {
                // Initialize here instead...
                initialize();
                window.mainWinFrm.setLocationRelativeTo(null);
                window.mainWinFrm.setMinimumSize(new Dimension(400, 200));
                window.mainWinFrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                window.mainWinFrm.pack();
                window.mainWinFrm.setVisible(true);             
            } 
            catch (Exception e) 
                {e.printStackTrace();} 
        }
    });
}

这仍然不合适，因为现在可以在他们被初始化之前访问课程的某些部分，相反，我更愿意做更像......

public static void main(String[] args) 
{
    EventQueue.invokeLater(new Runnable() 
    {
        public void run()
        {
            // Initialise the system look and feel...
            try 
            {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) 
            {
            }
            Gui window = new Gui();
            window.mainWinFrm.setLocationRelativeTo(null);
            window.mainWinFrm.setMinimumSize(new Dimension(400, 200));
            window.mainWinFrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            window.mainWinFrm.pack();
            window.mainWinFrm.setVisible(true);             
        }
    });
}

public Gui() 
{   
    initialize();
}

private void initialize() 
{
    mainWinFrm = new JFrame();
    mainWinFrm.setTitle("Inventory Tool");

    JMenuBar menuBar = new JMenuBar();
    mainWinFrm.getContentPane().add(menuBar, BorderLayout.NORTH);
    .....//allot more GUI staff getting initialize
}

Answer 2

更好的方法：桂班：

public class Gui {
private JFrame mainWinFrm;

public Gui() {
    initialize();

}

private void initialize() {
    mainWinFrm = new JFrame();
    mainWinFrm.setTitle("Inventory Tool");

    JMenuBar menuBar = new JMenuBar();
    mainWinFrm.getContentPane().add(menuBar, BorderLayout.NORTH);

}

public static void startGui() {
    try {
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    } catch (Exception ex) {
    }

    try {

        Gui window = new Gui();
        window.mainWinFrm.setLocationRelativeTo(null);
        window.mainWinFrm.setMinimumSize(new Dimension(400, 200));
        window.mainWinFrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.mainWinFrm.pack();
        window.mainWinFrm.setVisible(true);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

}

和MainClass：

public class MainClass {
public static void main(String[] args) 
{
 Gui.startGui();
}

}

这是更好的方式，因为它没有创建任何额外的对象。

试图了解GUI Swing和线程

2 个答案: