IOS:CS193p fall2013 assignment2 task2:add a button to let user to restart the game

问题

I am learning the course CS193P(IOS develop) on itunes and I just started assignment2. I got stuck on the task that asks me to restart the game. A little bit background on the project: I am writing code for the newly added action method for the restart button in my CardGameViewController. I have two private properties: game and deck. I use lazy initialization in the CardGameViewController to initialize them when user first touch a button(flip a card).(The original project that the professor went over in the lecture is just some cards on the UI and user can flip them around and match them,without the restart function, which is the one I am asked to add in the homework.) In order for the user to restart the game, I think I need to reinitialize the two properties I mentioned above and update the UI. I tried the following code but the program crashed when I touch the button I just added:

- (IBAction)touchRestartButton:(UIButton *)sender
{
    self.game = nil;
    self.theDeck = nil;
    // Maybe I also need to initialize the two properties again here using some code which I cannot figure out right now.... 
    [self updateUI];
}

Can anyone explain to me how to reinitialize a property in objective-c?(I also tried [self.game release], but the complier prevented me to do this because it says it is in ARC mode) Or is there any other way to finish this restarting game task?

来源：https://stackoverflow.com/questions/24937453/ioscs193p-fall2013-assignment2-task2add-a-button-to-let-user-to-restart-the-ga