example: Add some helper code to debug focus

src/DockWidgetBase.cpp

@@ -217,6 +217,13 @@ void DockWidgetBase::setWidget(QWidgetOrQuick *w)
 
     d->widget = w;
     setSizePolicy(w->sizePolicy());
+
+    if (w->focusPolicy() == Qt::NoFocus) {
+        setFocusProxy(nullptr);
+    } else {
+        setFocusProxy(w);
+    }
+
     Q_EMIT widgetChanged(w);
     setWindowTitle(uniqueName());
 }