Question

我正在尝试改进自己的java编程。

我要做的是，我有一个菜单和子菜单，例如我点击文件菜单，然后选择转换器（子菜单），我希望它为我的转换程序打开新窗口。

这是我的转换器窗口

public class Converter extends JFrame {

    private static final long   serialVersionUID    = 1L;
    private MoneyDetails        convertMe           = new MoneyDetails();
    private JLabel              tlLabel             = new JLabel("     Amount of TL");
    private JLabel              dollarsLabel        = new JLabel("Amount of Dollars");
    private JTextField          tlField             = new JTextField("0.0");
    private JTextField          dollarsField        = new JTextField("0.0");
    private JButton             tlButton            = new JButton("Convert to $");
    private JButton             dollarsButton       = new JButton("<<< Convert to TL");
    private JButton             setRates            = new JButton("Set Rates");

    public Converter() {
        JPanel dataPanel = new JPanel(new GridLayout(2, 2, 12, 6));
        dataPanel.add(tlLabel);

        dataPanel.add(dollarsLabel);
        dataPanel.add(tlField);
        dataPanel.add(dollarsField);
        JPanel buttonPanel = new JPanel();
        buttonPanel.add(tlButton);
        buttonPanel.add(dollarsButton);
        Container container = getContentPane();
        container.add(dataPanel, BorderLayout.CENTER);
        container.add(buttonPanel, BorderLayout.SOUTH);
        tlButton.addActionListener(new TLConverter());
        dollarsButton.addActionListener(new DollarsConverter());
        buttonPanel.add(setRates);
    }
    private class TLConverter implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            try {
                String input = tlField.getText();
                double tl = Double.parseDouble(input);
                convertMe.setTL(tl);
                double dollars = convertMe.getDollars();
                dollarsField.setText(String.format("%.2f", dollars));
            } catch (Exception ex) {
                JOptionPane.showMessageDialog(null, "Please enter the amount that will be converted.");
            }
        }
    }

    private class DollarsConverter implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String input = dollarsField.getText();
            double dollars = Double.parseDouble(input);
            convertMe.setDollars(dollars);
            double tl = convertMe.getTL();
            tlField.setText(String.format("%.2f", tl));
        }
    }

    public static void main(String[] args) {
        Converter theGUI = new Converter();
        theGUI.setTitle("TL to $ or $ to TL Converter");
        theGUI.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        theGUI.pack();
        theGUI.setVisible(true);
    }
}

这是我的转换器类中的菜单

private JMenuBar menuBar = new JMenuBar(); // Window menu bar
public Converter(String title) {
    setTitle(title);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setJMenuBar(menuBar); // Add the menu bar to the window
    JMenu fileMenu = new JMenu("File"); // Create File menu
    JMenu elementMenu = new JMenu("Elements"); // Create Elements menu
    JMenuItem subTest = new JMenuItem("Test");
    menuBar.add(fileMenu); // Add the file menu
    menuBar.add(elementMenu); // Add the element menu

    fileMenu.add(subTest);

  }

public static void main(String [] args)
{

Converter window = new Converter("Para Dönüstürücü"); 
window.setBounds(30, 30, 300, 300);
window.setVisible(true);
Converter theGUI = new Converter(); 

}

当我点击我的子菜单时，我希望它打开我的对流窗口。我怎么能这样做？

Answer 1

你需要的是一个事件监听器，如下所示：

fileMenu.addSelectionListener(new SelectionAdapter() {
      public void widgetSelected(SelectionEvent e) {
        new Converter();
      }
    });

您可以看到更完整的示例here。

Answer 2

您需要将Listener添加到menuItem，侦听器会在发生特定事件时为您提供回调，例如click，mouseout e.t.c。

您可以将ActionListener添加到menuItem，并在回调方法中显示您的GUI。

subTest.addActionListener(new ActionListener(){     
   public void actionPerformed(ActionEvent actionEvent){
       Converter convert = new Converter("Testing Opening this from Menu Item");
       convert.pack();
       convert.setVisible(true);
   }
});

您可以阅读Swing提供的所有不同听众here。

单击子菜单时，打开一个额外的窗口

2 个答案: