Popup 中的导航问题以及如何使用 setLocationRelativeto()

Question

我有一个 JButton 名为 Graphics:

当我按下它时，出现一个新的弹出菜单，用户选择屏幕分辨率：

我已将自定义图像添加到菜单项，我无法使用箭头键导航到任何菜单项。

第二个问题是弹出菜单没有固定在框架内，请告诉我如何让它固定在 JFrame 或图形按钮内。

我已经尝试过 KeyListener 但是没有用。

在下面的代码中，我创建了一个 JPopupMenu 并对其进行了初始化，在 KeyListener 函数中，我试图解决导航问题，但没有成功。

popgraphics=new JPopupMenu();
JMenuItem p1920=new JMenuItem();
JMenuItem p1536=new JMenuItem();
JMenuItem p1280=new JMenuItem();
p1920.setIcon(new ImageIcon(getClass().getResource("icons\1920p.png")));
p1536.setIcon(new ImageIcon(getClass().getResource("icons\1536p.png")));
p1280.setIcon(new ImageIcon(getClass().getResource("icons\1280p.png")));
p1920.setBorder(b1);
// p1920.setText("1920x1080 Pixels");
// p1536.setText("1536x1440 Pixels");
// p1280.setText("1280x720 Pixels");

p1920.setFont(new Font("MV Boli",0,14));
p1536.setFont(new Font("MV Boli",0,14));
p1280.setFont(new Font("MV Boli",0,14));

p1920.setOpaque(false);
p1536.setOpaque(false);
p1536.setOpaque(false);

// popgraphics.setSelected(null);
// popgraphics.setSelectionModel(SingleSelectionModel);
popgraphics.addKeyListener(new KeyListener()
{

    @Override
    public void keyTyped(KeyEvent e) {
        if(e.getKeyChar()==(char)38)
        {
            if(popgraphics.getSelectionModel().getSelectedIndex()==1)
            {
                popgraphics.getSelectionModel().setSelectedIndex(3);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==2)
            {
                popgraphics.getSelectionModel().setSelectedIndex(1);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==3)
            {
                popgraphics.getSelectionModel().setSelectedIndex(2);
            }
        }
        if(e.getKeyChar()==(char)40)
        {
            if(popgraphics.getSelectionModel().getSelectedIndex()==1)
            {
                popgraphics.getSelectionModel().setSelectedIndex(2);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==2)
            {
                popgraphics.getSelectionModel().setSelectedIndex(3);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==3)
            {
                popgraphics.getSelectionModel().setSelectedIndex(1);
            }
        }
    }

    @Override
    public void keyPressed(KeyEvent e) {
        if(e.getKeyChar()==(char)38)
        {
            if(popgraphics.getSelectionModel().getSelectedIndex()==1)
            {
                popgraphics.getSelectionModel().setSelectedIndex(3);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==2)
            {
                popgraphics.getSelectionModel().setSelectedIndex(1);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==3)
            {
                popgraphics.getSelectionModel().setSelectedIndex(2);
            }
        }
        if(e.getKeyChar()==(char)40)
        {
            if(popgraphics.getSelectionModel().getSelectedIndex()==1)
            {
                popgraphics.getSelectionModel().setSelectedIndex(2);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==2)
            {
                popgraphics.getSelectionModel().setSelectedIndex(3);
            }
            else if(popgraphics.getSelectionModel().getSelectedIndex()==3)
            {
                popgraphics.getSelectionModel().setSelectedIndex(1);
            }
        }
    }

    @Override
    public void keyReleased(KeyEvent e) {
    }
});

popgraphics.add(p1280);
popgraphics.add(p1536);
popgraphics.add(p1920);
Point p=graghics.getLocation();
popgraphics.setLocation(p);
popgraphics.setBackground(new Color(20,20,20));
popgraphics.setOpaque(false);

如果需要任何其他信息，请告诉我。

Answer 1

这是一个简单的程序，显示带有大图标的 JButton。 JPopupMenu 连接到 JButton。 JPopupMenu 包含两个 JMenuItem，其中每个都有自己独立的图标。运行程序。将鼠标指针放在 JButton 上。调出 JPopupMenu。（在我的 Windows 10 机器上，我单击鼠标右键显示 JPopupMenu。）然后按键盘上的向下箭头键。

import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPopupMenu;

public class PopupTst {

    private void createAndDisplayGui() {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Icon ico = new ImageIcon("first icon"); // replace with actual path to icon.
        JButton button = new JButton(ico);

        JPopupMenu popup = new JPopupMenu();
        Icon ico2 = new ImageIcon("second icon"); // replace with actual path to icon.
        JMenuItem one = new JMenuItem(ico2);
        popup.add(one);
        Icon ico3 = new ImageIcon("third icon"); // replace with actual path to icon.
        JMenuItem two = new JMenuItem(ico3);
        popup.add(two);

        button.setComponentPopupMenu(popup);

        frame.add(button);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        PopupTst instance = new PopupTst();
        EventQueue.invokeLater(() -> instance.createAndDisplayGui());
    }
}

Popup 中的导航问题以及如何使用 setLocationRelativeto()

Navigation problem in Popup and how to use setLocationRelativeto()

java

swing

jpopupmenu