QTextBrowser::highlighted() signal not being sent when TAB key is used to navigate links?

Robert Hairgrove

I have been successfully able to add a status bar to a dialog which displays different QTextBrowser widgets on each page of a tab widget. There are various external links (URLs) in the pages. When I hover over a link with the mouse, the text of the URL is displayed in the status bar just like in most browsers.

However, I noticed that I can navigate the links by using the TAB key. It seems like the link is "highlighted" when I focus on a link, because a focus rectangle is drawn around the link by the text browser. I have connected a slot for each browser widget to the highlighted(const QUrl &) signal emitted by the text browser, wishing to display the link in the status bar, too, but nothing happens.

My current setup (for one browser widget; there are nine of them) is as follows:
I have installed an event filter on each browser widget to catch the HoverEvent; each widget also has the window attribute WA_Hover set. Here is my code for the event filter (this works OK):

bool DlgAbout::eventFilter(QObject *obj, QEvent *event)
{
  QTextBrowser *browser = qobject_cast<QTextBrowser*>(obj);
  if (browser &&
         (event->type() == QEvent::HoverEnter
      || event->type() == QEvent::HoverMove
      || event->type() == QEvent::HoverLeave)) {
    QHoverEvent * pHover = static_cast<QHoverEvent*>(event);
    if (event->type() == QEvent::HoverEnter
     || event->type() == QEvent::HoverMove) {
      QPoint pt = pHover->pos();
      QString anchor = browser->anchorAt(pt);
      if (!anchor.isEmpty()) {
        // sb_ is a pointer to the status bar, a member variable:
        sb_->showMessage(anchor);
      } else {
        sb_->clearMessage();
      }
      return true;
    } else if (event->type() == QEvent::HoverLeave) {
      sb_->clearMessage();
      return true;
    }
  }
  return QObject::eventFilter(obj, event);
}

I have slots like this one to catch the highlighted() signal:

void DlgAbout::on_txtQt_highlighted(const QUrl &url)
{
  sb_->showMessage(url.toDisplayString());
}

And here is the connection syntax:

  connect(ui->txtQt, QOverload<const QUrl &>::of(&QTextBrowser::highlighted),
          this, &DlgAbout::on_txtQt_highlighted);

The overload seems still to be necessary, although the version taking a const QString & has apparently been marked as deprecated since Qt 5.15 (I am using Qt 5.15.5).

Any help would be greatly appreciated, as usual.

Robert Hairgrove

Is there some other signal I should be connecting to, or a property of the underlying QTextDocument that would help retrieve the URL which is currently focused?