Show JMenu in JPanel without frame.setJMenuBar

Question

我想在 Jpanel 中添加一个 JMenuBar。我试过了：

 p.add(menubar, BorderLayout.NORTH);

另外：我不想在JFrame上使用JSetMenu方法，因为我目前正在制作一个Astah插件，我希望Jpanel（Jmenubar所在的位置）在Astah中。

如何将 JMenuBar 设置为 Jpanel，使其位于顶部？我想把所有内容放在Jpanel中，然后放在Astah中。

将其放入 Astah 的代码：

import com.change_vision.jude.api.inf.project.ProjectAccessor;
import com.change_vision.jude.api.inf.project.ProjectAccessorFactory;
import com.change_vision.jude.api.inf.project.ProjectEvent;
import com.change_vision.jude.api.inf.project.ProjectEventListener;
import com.change_vision.jude.api.inf.ui.IPluginExtraTabView;
import com.change_vision.jude.api.inf.ui.ISelectionListener;
import javax.swing.*;
import java.awt.*;
public class showobjects extends JPanel implements IPluginExtraTabView, ProjectEventListener {
public showobjects () {
    initComponents();
}
private void initComponents() {
    setLayout(new BorderLayout());
    add(createLabelPane());
    addProjectEventListener();
}
private void addProjectEventListener() {
    try {
        ProjectAccessor projectAccessor = ProjectAccessorFactory.getProjectAccessor();
        projectAccessor.addProjectEventListener(this);
    } catch (ClassNotFoundException e) {
        e.getMessage();
    }
}
private Container createLabelPane() {
    JLabel label = new JLabel("showobjects ");
    JScrollPane pane = new JScrollPane(label);
    showobjects  app = new showobjects ();
    JPanel mainJpanel  = app.createJPanel();

    return mainJpanel;
}
@Override
public void projectChanged(ProjectEvent e) {
}
@Override
public void projectClosed(ProjectEvent e) {
}
@Override
public void projectOpened(ProjectEvent e) {
}
@Override
public void addSelectionListener(ISelectionListener listener) {
}
@Override
public Component getComponent() {
    return this;
}
@Override
public String getDescription() {
    return "Show showobjects  here";
}
@Override
public String getTitle() {
    return "showobjects ";
}
public void activated() {
}
public void deactivated() {
}
}

Answer 1

我做了一个非常简单的测试，它对我来说工作得很好。根据我从您的代码中可以推断出的内容，您正在使用...

mainJPanel.add(AuguSoftModellerobjectsNew.createMenuBar());

这会将JMenuBar置于面板的CENTRE（或默认）位置，该位置将被您在那里添加的其他组件隐藏

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
    public static void main(String[] args) {
        new Test();
    }
    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }
                JMenuBar mb = new JMenuBar();
                mb.add(new JMenu("Test"));
                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(mb, BorderLayout.NORTH);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }
    public class TestPane extends JPanel {
        public TestPane() {
        }
        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }
}