我可能迟到了， 7
请使用 UIPopOverViewConotroller

I might be very late to answer but for new user from iOS 7 please use the following line in your UIViewController i,e contentViewController of your UIPopOverViewConotroller

-(void) viewDidAppear:(BOOL)animated{
    [super viewDidAppear:animated]
    self.preferredContentSize=myTableView.contentSize;
}

希望这将有助于iOS 7用户。

Hope this will help for iOS 7 user.