Java Swing：在应用程序的 JFrame 上跟随鼠标光标的“永久工具提示”提示

Question

我想创建一个类似工具提示（提示）的小窗口，该窗口将根据请求弹出，然后在应用程序的JFrame 上的任意位置跟随鼠标光标，直到它稍后被销毁。它确实是一个全局提示消息，要求用户执行特定任务（在许多不同的窗口之间），一旦他们这样做了，它就会消失。例如：

GlobalToolTip panelHint = new GlobalToolTip("Global hint message.");
panelHint.show(); //Will remain visible and follow mouse
... //Waiting for user to perform a specific action or cancel
panelHint.hide(); //Hidden/destroyed here

我希望创建我自己的从JToolTip/JPanel 扩展的类，或者尽可能覆盖默认的工具提示行为。也许使用应用程序 JFrame 的 JLayeredPane 或 glassPane？ 我检查了一些其他解决方案，但都仅适用于单个组件的行为。我还尝试在 glassPane 上有一个 JPanel，但它没有正确地绘制在其他一些窗口内容上。也许我没有在正确的地方调用它的绘制方法？

这似乎应该是一个很容易解决的问题，但我没能做到。任何帮助将不胜感激。

Answer 1

就我个人而言，我不会为 glassPane 烦恼，也不会为试图让 JToolTip 或 ToolTipManager 做他们不应该做的事情而烦恼。我只会制作一个模仿 JToolTip 的 JLabel：

import java.awt.AWTEvent;
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.Point;
import java.awt.Window;

import java.awt.event.MouseEvent;
import java.awt.event.AWTEventListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JToggleButton;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

public class FollowTip {
    private JWindow tip;

    private final AWTEventListener mouseHandler = e -> {
        Window window = tip.getOwner();
        MouseEvent event = null;

        switch (e.getID()) {
            case MouseEvent.MOUSE_ENTERED:
            case MouseEvent.MOUSE_MOVED:
            case MouseEvent.MOUSE_DRAGGED:
                event = (MouseEvent) e;
                if (window.isAncestorOf(event.getComponent())) {
                    Point loc = event.getLocationOnScreen();
                    tip.setLocation(loc.x + 10, loc.y + 10);
                    tip.setVisible(true);
                }
                break;
            case MouseEvent.MOUSE_EXITED:
                event = (MouseEvent) e;
                Point p = SwingUtilities.convertPoint(
                    event.getComponent(), event.getPoint(), window);
                if (!window.contains(p)) {
                    tip.setVisible(false);
                }
                break;
            default:
                break;
        }
    };

    public FollowTip(String text,
                     Window window) {

        JLabel tipLabel = new JLabel(text);

        tipLabel.setForeground(UIManager.getColor("ToolTip.foreground"));
        tipLabel.setBackground(UIManager.getColor("ToolTip.background"));
        tipLabel.setFont(UIManager.getFont("ToolTip.font"));
        tipLabel.setBorder(UIManager.getBorder("ToolTip.border"));

        tip = new JWindow(window);
        tip.setType(Window.Type.POPUP);
        tip.setFocusableWindowState(false);
        tip.getContentPane().add(tipLabel);
        tip.pack();
    }

    public void activate() {
        Window window = tip.getOwner();
        window.getToolkit().addAWTEventListener(mouseHandler,
            AWTEvent.MOUSE_EVENT_MASK | AWTEvent.MOUSE_MOTION_EVENT_MASK);

        Point p = window.getMousePosition();
        if (p != null) {
            SwingUtilities.convertPointToScreen(p, window);
            tip.setLocation(p.x + 10, p.y + 10);
            tip.setVisible(true);
        }
    }

    public void deactivate() {
        Window window = tip.getOwner();
        window.getToolkit().removeAWTEventListener(mouseHandler);

        tip.setVisible(false);
    }

    static void showWindow() {
        Object[][] data = new Object[12][];
        Object[] headings = new Object[data.length];
        for (int i = 0; i < data.length; i++) {
            data[i] = new Object[data.length];
            for (int j = 0; j < data[i].length; j++) {
                data[i][j] = (i + 1) * (j + 1);
            }
            headings[i] = i;
        }

        JTable table = new JTable(data, headings);

        JToggleButton button = new JToggleButton("Active");
        JPanel buttonPanel = new JPanel();
        buttonPanel.add(button);

        JFrame frame = new JFrame("FollowTip");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(new JScrollPane(table));
        frame.getContentPane().add(buttonPanel, BorderLayout.PAGE_END);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);

        FollowTip tip = new FollowTip("This is a tip", frame);

        button.addActionListener(e -> {
            if (button.isSelected()) {
                tip.activate();
            } else {
                tip.deactivate();
            }
        });
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(() -> showWindow());
    }
}