Настройка поведения QToolTip

Когда убираем курсор с линии, то всплывающее окно с информацией исчезает

Canvas.cpp

@@ -598,15 +598,28 @@ void Canvas::paintEvent(QPaintEvent* event)
     }
 }
 
+void Canvas::leaveEvent(QEvent* event)
+{
+    Q_UNUSED(event);
+    QToolTip::hideText();
+}
+
 #ifdef _DEBUG
 void Canvas::showObjectTag(QPointF pos)
 {
     QPointF l = screenToLogical(pos);
     Line* lineUnderCursor = findAt(l, 2.0);
     if (lineUnderCursor && lineUnderCursor != draggedLine) {
-        QString Text = QString("Tag Line: %1").arg(lineUnderCursor->get_tag());
+        QPointF p1(*lineUnderCursor->p1.x, *lineUnderCursor->p1.y);
+        QPointF p2(*lineUnderCursor->p2.x, *lineUnderCursor->p2.y);
+        QLineF info_line(p1, p2);
+        QString Text = QString("Line %1\nLength = %2mm")
+            .arg(lineUnderCursor->get_tag() + 1)
+            .arg(info_line.length());
         QToolTip::showText(mapToGlobal(pos.toPoint()), Text, this);
     }
+    else 
+        QToolTip::hideText();
 }
 #endif
 

Canvas.h

@@ -60,6 +60,7 @@ protected:
     void mouseMoveEvent(QMouseEvent* event) override;
     void mouseReleaseEvent(QMouseEvent* event) override;
     void paintEvent(QPaintEvent* event) override;
+    void leaveEvent(QEvent* event) override;
 
 private: