My question is, how can i track the mouse 'click' event in my QGraphicsView?
For that you will need to properly handle mouse press and mouse release event of the graphics item and then emit a signal from the item.
Thats how things are done in normal pushbuttons also. But for graphics item, you will need to decide when you want to emit the clicked() signal... on mouse press, on mouse release, duration between the press and release, etc.