Ok, I have a QGraphicsScene full of QGraphicItem's.
What I hope to achieve is to somehow "assign" a QString to each of the QGraphicItem's when they are created.
Ex:
Qt Code: 
  1. create QGraphicItem
  2.     assign QString "this data" to it
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By doing that, when a user clicks on the respective QGraphicItem, I can call a function passing as an argument the previously assigned QString.

Qt Code: 
  1. when I click on QGraphicItem
  2.      call useData(assigned QString)
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Makes sense? Hope so.