java – 将JApplet添加到JFrame中

我试图在JFrame中查看JApplet.

Class: Paint
public void paint(Graphics g) {
  g.drawString("hi", 50, 50);
}

public static void main(String args[]) {
  JFrame frame = new JFrame("test");
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame.setJMenuBar(methodThatReturnsJMenuBar());

  JPanel panel = new JPanel(new BorderLayout());
  frame.add(panel);

  JApplet applet = new Paint();
  panel.add(applet, BorderLayout.CENTER);
  applet.init();
  frame.pack();

  frame.setVisible(true);
}

小程序显示在窗口中,但没有背景(它是透明的),当我单击菜单时,列表被覆盖.如何制作以便菜单列表不被覆盖,并且有背景？

编辑：当我绘制一个白色矩形时,它修复了背景问题,但菜单列表仍然被覆盖.

解决方法:

我会将我的GUI创建用于制作JPanel,然后在JApplet或JFrame中使用JPanel.例如,

import java.awt.*;
import javax.swing.*;

public class MyPanel extends JPanel {
   private static final Dimension PREF_SIZE = new Dimension(400, 300);

   @Override
   protected void paintComponent(Graphics g) {
      super.paintComponent(g);
      g.drawString("hi", 50, 50);
   }

   @Override
   public Dimension getPreferredSize() {
      return PREF_SIZE;
   }

   public JMenuBar methodThatReturnsJMenuBar() {
      JMenu menu = new JMenu("Menu");
      JMenuBar menuBar = new JMenuBar();
      menuBar.add(menu);
      return menuBar;
   }
}

然后在applet中使用：

import javax.swing.JApplet;

public class MyApplet extends JApplet {
   public void init() {
      try {
         javax.swing.SwingUtilities.invokeAndWait(new Runnable() {
            public void run() {
               createGUI();
            }
         });
      } catch (Exception e) {
         System.err.println("createGUI didn't successfully complete");
      }
   }

   private void createGUI() {
      getContentPane().add(new MyPanel());
   }
}

或者在JFrame中：

import javax.swing.JFrame;

public class MyStandAlone {
   private static void createAndShowUI() {
      MyPanel myPanel = new MyPanel();
      JFrame frame = new JFrame("MyPanel");
      frame.getContentPane().add(myPanel);
      frame.setJMenuBar(myPanel.methodThatReturnsJMenuBar());
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.pack();
      frame.setLocationRelativeTo(null);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      java.awt.EventQueue.invokeLater(new Runnable() {
         public void run() {
            createAndShowUI();
         }
      });
   }
}

标签：java,swing,jframe,japplet
来源： https://codeday.me/bug/20190518/1128160.html