presentViewController and detect dismiss

hi, i need to show a custom transparent view for insert a pin password but i need to detect inside the view parent when this view will dismiss, any suggestions?


i use


DialogPIN *NView = [[DialogPIN alloc] initWithNibName:nil bundle:nil];

[self presentViewController:NView animated:NO

completion:nil];


any possibility to add a block code in the same presentviewcontroller?