NewItemDialog uses dynamically generated control widgets for model data as well. Added a WidgetHelper class to consolidate identical source code for ItemDetailMapper and NewItemDialog.

widgethelper.h

@@ -0,0 +1,17 @@
+#ifndef WIDGETHELPER_H
+#define WIDGETHELPER_H
+
+#include "model/metadata.h"
+
+class QWidget;
+
+class WidgetHelper {
+ public:
+  static QWidget* createControlWidget(const UserRoles role, QWidget* parent);
+  static QWidget* createComboBox(const UserRoles role, QWidget* parent);
+
+ private:
+  explicit WidgetHelper();
+};
+
+#endif  // WIDGETHELPER_H