Hi Tarek,
that looks like a good "solution", but I think I might have an even better idea.
As you cannot determine the button's size at runtime, you could just get the editButton.title (which returns a NSString) and calculate how wide this string would be under usage of the button's font. (Which should be systemOfFontSize:12.0 I guess). Then you could set frame.width of the transparent toolbar to this value and add the width for the addButton:
SCTableViewController.m >> viewWillAppear:
CGSize buttonSize = [self.editButton.title sizeWithFont:[UIFont systemFontOfSize:12.0]];
// Create the toolbar that will hold the Add and Edit buttons
SCTransparentToolbar* toolbar = [[SCTransparentToolbar alloc] initWithFrame:CGRectMake(0, 0, 80 + buttonSize.width, 44.01)];
What do you think, Tarek?