UI/logic separation - could anyone recommend a good source of knowledge

Question

Hey!

I am a newcomer in the area of user interfaces. I am working now on the design of a user interface for a piece of code I have in C++ language. I've decided to use QT for creating the UI.

Now, what I am mostly concerned in is what is the proper way of separating the UI from the logic. I have some data layer, which should be accessible from different parts of my UI (different widgets, different windows). Some UI components may represent or even alter the data simultaneously.

Should I represent the data layer by a singleton and use this singleton in UI? The alternative is probably to transfer a pointer to the data to each and any UI component, which, IMHO, smells bad.

In adition, where is the best place to translate between UI-related data-structures, like QList, QVector, QString and the data structures I use in my data layer (STL + Boost). Maybe some proxy layer is required in the middle?

Can anyone recommend me a good book, article or any other source of knowledge related to my question? Any ideas or tips you can give me are also very welcomed.

Thanks.

Answer 1

Model-View-Controller pattern is what you should rely on. http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller

Answer 2

In adition, where is the best place to translate between UI-related data-structures, like QList, QVector, QString and the data structures I use in my data layer (STL + Boost). Maybe some proxy layer is required in the middle?

Two options come to mind. You could provide functions in your data layer to return the Qt data structures, or you could wrap the Qt UI Widget classes around your own classes which take STL + Boost data structures, convert them, and pass them to the Qt Widgets.

The first option is probably easier and quicker to implement, but the second option better preserves the separation between how your data is stored and the UI.

Answer 3

Qt provides a powerful mechanism for the Model-View pattern.

It's all documented in Qt documentation : Model/View Programming.

Basically, you'll have to implement your own Model classes, which will be the link between your logic and the UI.