我正在尝试将 Apple 的游戏中心集成到我的应用程序中。我可以成功地将分数发布到排行榜,并显示排行榜,但是当我尝试关闭排行榜模式视图时,问题就来了。我从游戏工具包编程指南([url]http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/GameKit_Guide/LeaderBoards/LeaderBoards.html[/url])中遵循了苹果的代码方向.
我的游戏中心代码如下:
-(BOOL)isGameCenterAvailable{
// Check for presence of GKLocalPlayer class.
BOOL localPlayerClassAvailable = (NSClassFromString(@"GKLocalPlayer")) != nil;
// The device must be running iOS 4.1 or later.
NSString *reqSysVer = @"4.1";
NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
BOOL osVersionSupported = ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending);
return (localPlayerClassAvailable && osVersionSupported);
}
- (void) authenticateLocalPlayer
{
if([self isGameCenterAvailable]){
GKLocalPlayer *localPlayer = [GKLocalPlayer localPlayer];
[localPlayer authenticateWithCompletionHandler:^(NSError *error) {
if (localPlayer.isAuthenticated)
{
// Perform additional tasks for the authenticated player.
}
}];
}
}
- (void) reportScore: (int64_t) score forCategory: (NSString*) category
{
GKScore *scoreReporter = [[[GKScore alloc] initWithCategory:category] autorelease];
scoreReporter.value = score;
[scoreReporter reportScoreWithCompletionHandler:^(NSError *error) {
if (error != nil)
{
// handle the reporting error
}
}];
}
- (void) showLeaderboard
{
GKLeaderboardViewController *leaderboardController = [[GKLeaderboardViewController alloc] init];
if (leaderboardController != nil)
{
leaderboardController.leaderboardDelegate = self;
[self presentModalViewController: leaderboardController animated: YES];
}
//[leaderboardController release];
}
- (void)leaderboardViewControllerDidFinish:(GKLeaderboardViewController *)viewController
{
if([self modalViewController] != nil){
[self dismissModalViewControllerAnimated:YES];
}
}
-(IBAction)show{
[self showLeaderboard];
}
-(IBAction)submit{
[self reportScore:9 forCategory:kLeaderboardID];
}
Xcode 告诉我问题行是 [self dismissModalViewControllerAnimated:YES]; 它说我的访问权限不正确,我知道这意味着我正在尝试访问一个错误的指针,但我不明白为什么任何东西都不会无效。自我报告说它有一个 modalviewcontroller。我尝试了各种变体,但我完全困惑为什么它会给我错误。
任何帮助或建议将不胜感激。
提前致谢!