Make text in a JToolTip selectable and copyable

• download example.jar
• download src.zip
• repository

Code

JEditorPane hint = new JEditorPane();
hint.setEditorKit(new HTMLEditorKit());
hint.setEditable(false);
hint.setOpaque(false);

JCheckBox check = new JCheckBox();
check.setOpaque(false);

JPanel panel = new JPanel(new BorderLayout());
panel.add(hint);
panel.add(check, BorderLayout.EAST);

JPopupMenu popup = new JPopupMenu();
popup.add(new JScrollPane(panel));
popup.setBorder(BorderFactory.createEmptyBorder());

JEditorPane editor = new JEditorPane() {
  @Override public JToolTip createToolTip() {
    JToolTip tip = super.createToolTip();
    tip.addHierarchyListener(e -> {
      if ((e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED) != 0
            && e.getComponent().isShowing()) {
        panel.setBackground(tip.getBackground());
        popup.show(tip, 0, 0);
      }
    });
    return tip;
  }
};
editor.setEditorKit(new HTMLEditorKit());
editor.setText(HTML_TEXT);
editor.setEditable(false);
editor.addHyperlinkListener(e -> {
  JEditorPane editorPane = (JEditorPane) e.getSource();
  if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
    JOptionPane.showMessageDialog(editorPane, "You click the link with the URL " + e.getURL());
  } else if (e.getEventType() == HyperlinkEvent.EventType.ENTERED) {
    editorPane.setToolTipText("");
    Optional.ofNullable(e.getSourceElement())
        .map(elem -> (AttributeSet) elem.getAttributes().getAttribute(HTML.Tag.A))
        .ifPresent(attr -> {
          String title = Objects.toString(attr.getAttribute(HTML.Attribute.TITLE));
          String url = Objects.toString(e.getURL());
          // String url = Objects.toString(attr.getAttribute(HTML.Attribute.HREF));
          hint.setText(String.format("%s: %s", title, url, url));
          popup.pack();
        });
  } else if (e.getEventType() == HyperlinkEvent.EventType.EXITED) {
    editorPane.setToolTipText(null);
  }
});

• Override JComponent#createToolTip() method to add HierarchyListener to JToolTip
• Show JPopupMenu with JToolTip as parent when JToolTip is visible
• JToolTip hides behind JPopupMenu
• JPopupMenu adds a JPanel with a JEditorPane and a JCheckBox instead of a JMenuItem
• Hiding the parent JToolTip with the mouse cursor does not close the JPopupMenu, so you can click the internal JCheckBox or select the text in the JEditorPane and copy it with Ctrl-C, etc
• It is a normal JPopupMenu, so it is hidden when the focus is moved by clicking on the parent JFrame etc

References

• Make text in a JToolTip selectable and copyable(Japanese)