java - 如何在自己的私有(private)void中正确使用JFrame

Question

所以基本上我在这里有点困惑，我正在使用 Eclipse 的 WindowsPro Builder 插件，它使所有 JFrame 组件都在自定义的初始化()类中。这给我带来了一个问题，通常我在一开始就定义我的组件，这样我就可以通过我的程序公开访问它们。不，我有第二类，但我无法访问我的组件。例如，我无法弄清楚如何为整个初始化类制作统一的 ActionListener。

我也想从textarea获取输入，但是我该怎么做呢？当一切都超出范围时？正如您所看到的，我调用类 SaveToFile，在该类中我想从文本区域获取输入，但我该怎么做？

 import javax.swing.*;


 public class FunctionsGUI  {

private JFrame frame;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                FunctionsGUI window = new FunctionsGUI();
                window.frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the application.
 */
public FunctionsGUI() {
    initialize();

}

/**
 * Initialize the contents of the frame.
 */
private void initialize ()   {

    try {
          UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch(Exception e) {
          System.out.println("Error setting native LAF: " + e);
        }

    frame = new JFrame();
    frame.setBounds(100, 100, 571, 531);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    SpringLayout springLayout = new SpringLayout();
    frame.getContentPane().setLayout(springLayout);

    JTextPane textPane = new JTextPane();
    springLayout.putConstraint(SpringLayout.NORTH, textPane, 10, SpringLayout.NORTH, frame.getContentPane());
    springLayout.putConstraint(SpringLayout.WEST, textPane, 10, SpringLayout.WEST, frame.getContentPane());
    springLayout.putConstraint(SpringLayout.SOUTH, textPane, 462, SpringLayout.NORTH, frame.getContentPane());
    springLayout.putConstraint(SpringLayout.EAST, textPane, 545, SpringLayout.WEST, frame.getContentPane());
    frame.getContentPane().add(textPane);
    frame.setLocationRelativeTo(null);
    frame.setTitle("Calcolo");


    JMenuBar menuBar = new JMenuBar();
    frame.setJMenuBar(menuBar);

    JMenu mnFile = new JMenu("File");
    menuBar.add(mnFile);

    final JMenuItem mntmSave = new JMenuItem("Save");
    mntmSave.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            SaveToFile sv = new SaveToFile();
        }
    });
    mnFile.add(mntmSave);

    JMenu mnOptions = new JMenu("Options");
    menuBar.add(mnOptions);

    JMenu mnHelp = new JMenu("Help");
    menuBar.add(mnHelp);

    final JMenuItem AboutMenu = new JMenuItem("About");
    AboutMenu.addActionListener(new ActionListener() {

        public void actionPerformed(ActionEvent e) {
            if (e.getSource().equals(AboutMenu)) {
                 JDialog dialog = new JDialog();
                    dialog.setTitle("Search Dialog");
                    dialog.getContentPane().add(new JLabel("Just a test"));
                    dialog.setSize(300,300);
                    dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
                    dialog.setLocationRelativeTo(frame);
                    dialog.setVisible(true);

            if (e.getSource().equals(mntmSave));
                SaveToFile sv = new SaveToFile ();
            }
        }
    });
    mnHelp.add(AboutMenu);

}
}

Answer 1

WindowsPro Builder plugin for eclipse, and it makes all the JFrame components in a custom initialize () class.

initialize() 只是一个方法而不是一个类。这里的类是 FunctionsGUI 。

This creates a question for me, normally I define my components in the beginning so I can access them publicly trough my program.

这取决于你在做什么，但这可能是一个糟糕的设计。

No I have a second class, but i cant access my components.

实现一个 getter 来返回您需要的组件(甚至所有组件)。

As you can se i call the class SaveToFile, in that class i want to get the input from the textarea, but how would i do this?

例如，您可以将对 JTextField 的引用传递给构造函数中的 SaveToFile 类。