How to close current qml UI instance and load another

[firefox]

Hi,

I'm trying to make a application with qml UI and C++ backend.
When I run the application login screen comes up which is main.qml in my project.

I have another application.qml file which is the UI that should show up when login is successful.
What is the best way to achieve this? I'm not sure how to proceed here.

Thanks
firefox

Update: pls check https://forum.qt.io/topic/66164/show-different-qml-ui-from-c