英文:
JPopupMenu appears but seems to not react
问题
我遇到了让JPopupMenu正常工作的问题。
我期望的情况
当我用鼠标右键单击时,菜单应该弹出。然后我可以从菜单中选择一个项目并执行我想做的操作。
我实际得到的情况
当我右键单击时,菜单出现了,但之后我无法选择菜单项,或者至少我错过了正常菜单中已知的鼠标悬停高亮效果(我期望当前悬停的项目会被高亮显示,就像正常菜单中的情况一样)。
在此处查看问题(没有悬停高亮):
这是我的示例代码:
package com.mycompany.mavenproject2;
import java.awt.Dimension;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
public class PopupMenuTest {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel pane = new JPanel();
JPopupMenu popup = new JPopupMenu();
popup.add(new JMenuItem("A"));
popup.add(new JMenuItem("B"));
pane.setSize(300,300);
pane.add(popup);
pane.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if(SwingUtilities.isRightMouseButton(e)) {
popup.setLocation(e.getXOnScreen(), e.getYOnScreen());
popup.setVisible(true);
}
}
});
frame.setTitle("Test");
frame.add(pane);
frame.setPreferredSize(new Dimension(300,300));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
编辑
与正常工作的悬停效果的“正常”菜单进行比较:
编辑 #2
请查看当前(意外的)行为:
英文:
I've problems to get a JPopupMenu working correctly.
What I expect
The menu should pop up once I do a right click with my mouse. Then I can select an item from the menu and do whatever I want..
What I actually get
The menu appears once I do a right click but after that I can not select a menu item or at least I am missing the well known mouse hover highlight effect (I would expect that the item I am currently hovering is highlighted, like it is the case in the normal menu).
The see problem here (no highlight on hover):
Here is my example code:
package com.mycompany.mavenproject2;
import java.awt.Dimension;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
public class PopupMenuTest {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel pane = new JPanel();
JPopupMenu popup = new JPopupMenu();
popup.add(new JMenuItem("A"));
popup.add(new JMenuItem("B"));
pane.setSize(300,300);
pane.add(popup);
pane.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if(SwingUtilities.isRightMouseButton(e)) {
popup.setLocation(e.getXOnScreen(), e.getYOnScreen());
popup.setVisible(true);
}
}
});
frame.setTitle("Test");
frame.add(pane);
frame.setPreferredSize(new Dimension(300,300));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
Edit
Compare to a "normal" menu with working hovering:
Edit #2
Please see the current (unexpected) behaviour:
答案1
得分: 1
你需要使用JPopupMenu
的show
方法,而不是setVisible
方法。
以下是我测试过的代码。我正在运行Windows 10,并使用Java JDK 13.0.2,兼容Java 8。当鼠标悬停在上面时,会出现高亮显示。
import java.awt.Dimension;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
public class JPopupMenuTest implements Runnable {
public static void main(String[] args) {
SwingUtilities.invokeLater(new JPopupMenuTest());
}
@Override
public void run() {
JFrame frame = new JFrame();
JPanel pane = new JPanel();
pane.setPreferredSize(new Dimension(300, 300));
pane.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if (SwingUtilities.isRightMouseButton(e)) {
JPopupMenu popup = new JPopupMenu();
popup.add(new JMenuItem("A"));
popup.add(new JMenuItem("B"));
popup.show(e.getComponent(), e.getX(), e.getY());
}
}
});
frame.setTitle("JPopupMenu Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(pane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
英文:
You need to use the JPopupMenu
show
method, rather than the setVisible
method.
Here's the code I tested with. I'm running Windows 10 and using the Java JDK 13.0.2 with Java 8 compliance. I get the highlight on the mouse over.
import java.awt.Dimension;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
public class JPopupMenuTest implements Runnable {
public static void main(String[] args) {
SwingUtilities.invokeLater(new JPopupMenuTest());
}
@Override
public void run() {
JFrame frame = new JFrame();
JPanel pane = new JPanel();
pane.setPreferredSize(new Dimension(300, 300));
pane.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if (SwingUtilities.isRightMouseButton(e)) {
JPopupMenu popup = new JPopupMenu();
popup.add(new JMenuItem("A"));
popup.add(new JMenuItem("B"));
popup.show(e.getComponent(), e.getX(), e.getY());
}
}
});
frame.setTitle("JPopupMenu Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(pane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
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