Fix disconnect on null old page win Simple Browser example

Eliminates constant warnings from QObject on every new tab create

Change-Id: I93b3a2561a8a99932ea2a8c77cc12ded4a6906e7
Reviewed-by: Michal Klocek <michal.klocek@qt.io>
(cherry picked from commit bfae1b143acb9581ebc9396e0ba7e7e0fe5053d0)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 12 insertions, 11 deletions

diff --git a/examples/webenginewidgets/simplebrowser/webview.cpp b/examples/webenginewidgets/simplebrowser/webview.cpp
index 5bd0a5ef4..31be9f34c 100644
--- a/examples/webenginewidgets/simplebrowser/webview.cpp
+++ b/examples/webenginewidgets/simplebrowser/webview.cpp
@@ -133,17 +133,18 @@ inline QString questionForFeature(QWebEnginePage::Feature feature)
 
 void WebView::setPage(WebPage *page)
 {
-    WebPage *oldPage = qobject_cast<WebPage *>(QWebEngineView::page());
-    disconnect(oldPage, &WebPage::createCertificateErrorDialog, this,
-               &WebView::handleCertificateError);
-    disconnect(oldPage, &QWebEnginePage::authenticationRequired, this,
-               &WebView::handleAuthenticationRequired);
-    disconnect(oldPage, &QWebEnginePage::featurePermissionRequested, this,
-               &WebView::handleFeaturePermissionRequested);
-    disconnect(oldPage, &QWebEnginePage::proxyAuthenticationRequired, this,
-               &WebView::handleProxyAuthenticationRequired);
-    disconnect(oldPage, &QWebEnginePage::registerProtocolHandlerRequested, this,
-               &WebView::handleRegisterProtocolHandlerRequested);
+    if (auto oldPage = qobject_cast<WebPage *>(QWebEngineView::page())) {
+        disconnect(oldPage, &WebPage::createCertificateErrorDialog, this,
+                   &WebView::handleCertificateError);
+        disconnect(oldPage, &QWebEnginePage::authenticationRequired, this,
+                   &WebView::handleAuthenticationRequired);
+        disconnect(oldPage, &QWebEnginePage::featurePermissionRequested, this,
+                   &WebView::handleFeaturePermissionRequested);
+        disconnect(oldPage, &QWebEnginePage::proxyAuthenticationRequired, this,
+                   &WebView::handleProxyAuthenticationRequired);
+        disconnect(oldPage, &QWebEnginePage::registerProtocolHandlerRequested, this,
+                   &WebView::handleRegisterProtocolHandlerRequested);
+    }
     createWebActionTrigger(page,QWebEnginePage::Forward);
     createWebActionTrigger(page,QWebEnginePage::Back);
     createWebActionTrigger(page,QWebEnginePage::Reload);