Don't accept signals from hidden widgets, and don't propagate their f…

…orm value

src/Wt/WApplication.C

@@ -14,6 +14,7 @@
 #include "Wt/WDate"
 #include "Wt/WDefaultLoadingIndicator"
 #include "Wt/WException"
+#include "Wt/WFileUpload"
 #include "Wt/WMemoryResource"
 #include "Wt/WServer"
 #include "Wt/WTimer"
@@ -517,13 +518,11 @@ void WApplication::removeGlobalWidget(WWidget *)
 
 bool WApplication::isExposed(WWidget *w) const
 {
-  /*
-   * This not right: for example a file upload is usually hidden while
-   * uploading, but then could not receive the upload event
-
-  if (!w->isVisible())
+  // File uploads may be hidden when emitting a signal.
+  // Other hidden widgets should not emit signals.
+  if (!w->isVisible() && !dynamic_cast<WFileUpload*>(w))
     return false;
-  */
+
   if (!w->isEnabled())
     return false;
 

src/web/WebSession.C

@@ -2850,8 +2850,8 @@ void WebSession::propagateFormValues(const WEvent& e, const std::string& se)
 
     if (!request.postDataExceeded()) {
       WWidget *w = dynamic_cast<WWidget*>(obj);
-      if (w && !w->isEnabled())
-	continue; // Do not update form data of a disabled widget
+      if (w && (!w->isEnabled() || !w->isVisible()))
+	continue; // Do not update form data of a disabled or invisible widget
       obj->setFormData(getFormData(request, se + formName));
     } else
       obj->setRequestTooLarge(request.postDataExceeded());