Addressed the bug: 319404 (https://bugs.kde.org/show_bug.cgi?id=319404)
-> As suggested by Kevin, wrapped the existing QuickOpenModel with the QSortFilterProxyModel to produce a sorted list of functions in the Outline drop down menu.
-> Converted the indexes from the Proxy Model to the Source Model and vice-versa where ever necessary.
-> Analyzed the use cases of the Outline menu, and modified all it's functionalities and features corresponding to the Proxy Model.