UIAlertView与cocos2d和场景转换

Question

我目前在我的cocos2d应用程序中有一个场景，它有一个UIAlertView提醒用户，如果他们开始新游戏，它将删除旧游戏。一旦他们承认这一点，就应该转换到游戏场景。单击“是”按钮时出现以下错误：

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 
'-[__NSCFNumber count]: unrecognized selector sent to instance 0xa81afc0'

以下是代码：

-(id) init
{
    CCMenuItemSprite *newMenuItem = [CCMenuItemSprite itemWithNormalSprite:new
                                                             selectedSprite:newSelected
                                                             disabledSprite:nil
                                                                     target:self
                                                                   selector:@selector(onPlayClicked:)];

    CCMenu *menu = [CCMenu menuWithItems:nil];

    if ([name length] > 0) {
        [menu addChild:contMenuItem];
    }

    [menu addChild:newMenuItem];
    [menu addChild:optionMenuItem];
    [menu alignItemsVertically];
    menu.position = ccp(winSize.width/2, winSize.height - (winSize.height * 0.70));
    [self addChild:menu z:1];
}

- (void)onPlayClicked:(id)sender
{
    [[SimpleAudioEngine sharedEngine] playEffect:@"button.mp3"];
    NSString *name = [[GameManager sharedGameManager] getName];

    if ([name length] > 0) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Are you sure?" message:@"Starting a new game will delete your old game" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Yes", nil];
        [alert show];
    } else {
        [[CCDirector sharedDirector] replaceScene:[PlayScene scene]];
    }
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
    if (buttonIndex == 1) {
        [[GameManager sharedGameManager] resetGameState];
        [[CCDirector sharedDirector] replaceScene:[PlayScene scene]];
    }
}