QQuickWidget: update() when resetting updatePending in showEvent()

If updatePending is set, that means we want to call update()
eventually. If we just reset updatePending without calling
update(), we produce UI glitches.

Change-Id: Ie7353b2f5da567e196dbee8c113920e0e4702304
Task-number: QTCREATORBUG-16022
Reviewed-by: Robert Loehning <robert.loehning@qt.io>
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/src/quickwidgets/qquickwidget.cpp b/src/quickwidgets/qquickwidget.cpp
index 2120be768c..1a840b44bd 100644
--- a/src/quickwidgets/qquickwidget.cpp
+++ b/src/quickwidgets/qquickwidget.cpp
@@ -1099,12 +1099,16 @@ void QQuickWidget::mouseDoubleClickEvent(QMouseEvent *e)
 void QQuickWidget::showEvent(QShowEvent *)
 {
     Q_D(QQuickWidget);
-    d->updatePending = false;
     d->createContext();
-    if (d->offscreenWindow->openglContext())
+    if (d->offscreenWindow->openglContext()) {
         d->render(true);
-    else
+        if (d->updatePending) {
+            d->updatePending = false;
+            update();
+        }
+    } else {
         triggerUpdate();
+    }
     QWindowPrivate *offscreenPrivate = QWindowPrivate::get(d->offscreenWindow);
     if (!offscreenPrivate->visible) {
         offscreenPrivate->visible = true;