Dialogs: only return valid QPlatformDialogHelper if Qt Quick dialog is

If we don't do this, QQuickAbstractDialog::create will see that
m_handle is valid and call onCreate, which tries to call selectedFiles
and we get a crash.

Amends f9421abbdf4d2e2be06febf9f75a2b62e6875835.

Pick-to: 6.9 6.8 6.5
Change-Id: Id522e068c689a5bc5662466e446f99586bc7c738
Reviewed-by: Oliver Eftevaag <[email protected]>
(cherry picked from commit 93ea1a12ec532c77c22519062cb19007e6dd0db4)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>

1 files changed, 15 insertions, 5 deletions

diff --git a/src/quickdialogs/quickdialogsquickimpl/qquickdialogimplfactory.cpp b/src/quickdialogs/quickdialogsquickimpl/qquickdialogimplfactory.cpp
index 340695fe11..ffc27daaf0 100644
--- a/src/quickdialogs/quickdialogsquickimpl/qquickdialogimplfactory.cpp
+++ b/src/quickdialogs/quickdialogsquickimpl/qquickdialogimplfactory.cpp
@@ -29,25 +29,35 @@ std::unique_ptr<QPlatformDialogHelper> QQuickDialogImplFactory::createPlatformDi
     std::unique_ptr<QPlatformDialogHelper> dialogHelper;
     switch (type) {
     case QQuickDialogType::ColorDialog: {
-        dialogHelper.reset(new QQuickPlatformColorDialog(parent));
+        auto *quickPlatformDialog = new QQuickPlatformColorDialog(parent);
+        if (quickPlatformDialog->isValid())
+            dialogHelper.reset(quickPlatformDialog);
         break;
     }
 #if QT_CONFIG(quick_listview) && QT_CONFIG(quick_draganddrop)
     case QQuickDialogType::FileDialog: {
-        dialogHelper.reset(new QQuickPlatformFileDialog(parent));
+        auto *quickPlatformDialog = new QQuickPlatformFileDialog(parent);
+        if (quickPlatformDialog->isValid())
+            dialogHelper.reset(quickPlatformDialog);
         break;
     }
     case QQuickDialogType::FolderDialog: {
-        dialogHelper.reset(new QQuickPlatformFolderDialog(parent));
+        auto *quickPlatformDialog = new QQuickPlatformFolderDialog(parent);
+        if (quickPlatformDialog->isValid())
+            dialogHelper.reset(quickPlatformDialog);
         break;
     }
     case QQuickDialogType::FontDialog: {
-        dialogHelper.reset(new QQuickPlatformFontDialog(parent));
+        auto *quickPlatformDialog = new QQuickPlatformFontDialog(parent);
+        if (quickPlatformDialog->isValid())
+            dialogHelper.reset(quickPlatformDialog);
         break;
     }
 #endif
     case QQuickDialogType::MessageDialog: {
-        dialogHelper.reset(new QQuickPlatformMessageDialog(parent));
+        auto *quickPlatformDialog = new QQuickPlatformMessageDialog(parent);
+        if (quickPlatformDialog->isValid())
+            dialogHelper.reset(quickPlatformDialog);
         break;
     }
     default: