单击JButton时如何在JWIndow上显示图像

Question

我有一个带有帮助按钮的JMenuBar。当用户点击"帮助"时，我需要打开一个不同的窗口，上面有一个显示游戏说明的.jpg。当用户单击该窗口外部时，可以关闭同一窗口。我想我缺少代码，因为它不起作用：

窗口.java

public class Window extends JWindow
{
  //java.net.URL imgIntro = getClass().getResource("/images/intro.jpg");
  ImageIcon imIntro = new ImageIcon(getClass().getResource("/images/intro.jpg"));
  //java.net.URL imgRegles = getClass().getResource("/images/rules.jpg");
  ImageIcon imRules = new ImageIcon(getClass().getResource("/images/rules.jpg"));
  static Thread t = new Thread();
  static int thread = 0;
  static JButton bouton;
  static int X;
  static int Y;
  public Window( int X, int Y, int type) {
    super();
    Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
    setSize(X,Y);
    setLocation( (dim.width - X)/2 , (dim.height - Y)/2);
    setVisible(true);
    Container fen = getContentPane();
    if (type == 1 ) bouton = new JButton(imIntro);
    else            bouton = new JButton(imRules);
    bouton.setPreferredSize(new Dimension(X, Y) );
    fen.add( bouton);
    bouton.setVisible( true );
    show();

   /* if window introduction,
      just display for 5 secondes */
    if( type == 1 ) {
        try {
            Thread.sleep(5000);
            thread = 1;
        }
        catch( java.lang.InterruptedException ex ) {
            JOptionPane.showMessageDialog(null, "erreur");
            }
        dispose();
    }

    /* if window of rules
       only close it when user clicks */
    else if ( type == 2 ) {
        bouton.addActionListener( new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                     dispose();
                }
        });
    }
 }
}

菜单.java

    public class Menu extends JMenuBar implements ActionListener{
     Interface map;
            JMenu m5;
    public Menu(Interface map){
            super();
            this.map=map;
           m5 = new JMenu ("Help");//dislay instructions / rules
            this.add(m5);
    public void actionPerformed(ActionEvent evt){
//.../
                      else if(evt.getSource () == m5){
                          //new JWindow
                          Window rules = new Window( 700, 457, 2);
                      }
    }
    }

使用 MCVE 编辑

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.IOException;
import java.net.URISyntaxException;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
/**
 *
 * @author Mark
 */
public class Test {

    JFrame mainFrame = new JFrame ();
    JFrame instructions = new JFrame();

    public Test (){
     gui ();
}

    public void gui (){
        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainFrame.setSize(600, 400);
        mainFrame.setVisible(true);
        instructions.setSize(200, 200);
        JMenuBar mb = new JMenuBar ();
        JMenu help = new JMenu("Help");
        mb.add(help);
        JMenuItem instructionsMenu = new JMenuItem ("Instructions");
        help.add(instructions);

        mainFrame.setJMenuBar(mb);
        instructions.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e){
                instructions.setVisible(true);
                mainFrame.dispose();
            }

        });

    }


    public static void main(String[] args) throws IOException, URISyntaxException
    {
        new Test ();
    }
}

Answer 1

我建议您对说明窗口使用JDialog而不是JFrame。例如，请参阅此处。

public class Test {
    JFrame mainFrame = new JFrame();
    JDialog instructions = new JDialog(mainFrame);
    public Test() {
        gui();
    }
    public void gui() {
        instructions.setSize(200, 200);
        JMenuBar mb = new JMenuBar();
        JMenu help = new JMenu("Help");
        mb.add(help);
        JMenuItem instructionsMenu = new JMenuItem("Instructions");
        help.add(instructionsMenu);
        instructionsMenu.addActionListener(e -> instructions.setVisible(true));
        mainFrame.setJMenuBar(mb);
        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainFrame.setSize(600, 400);
        mainFrame.setVisible(true);
    }
    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new Test());
    }
}

笔记：

• 调用setVisible作为您为窗口执行的最后一件事。
• 在实际程序中，窗口中有组件，调用它们pack()而不是设置它们的大小。
• 从 EDT 开始摆动。

Answer 2

为什么你有一个没有 if 条件的 else-if 条件？这将创建语法错误。

此外，显示窗口的代码应如下所示：

dispose();
Window rules = new Window( 700, 457, 2);
rules.show();