Facebook SDK Singleton在xcode中自動登錄后才能發布？

Question

按照Facebook教程的指示，我已經在APPDelegate中使用了Facebook SDK，但是我試圖將其放入單例方法中。 我發現的每個教程似乎都是針對較舊版本的SDK的，但是我成功地通過此http://indiedevstories.com/2011/08/30/a-facebook-reusable-class/

我遇到2個問題，第一個問題發布在這里，這是第二個問題：

我希望有一個按鈕可以發布到Facebook，但是如果用戶未登錄，則他們需要先登錄然后發布（不必先按下單獨的登錄按鈕）。 我可以很好的登錄，也可以發布好，但是我不能一起做。 如果未登錄，則郵政編碼顯示登錄屏幕，但登錄后不會進入帖子屏幕。您必須再次按發布。 如果您嘗試登錄但已經登錄，那么什么也不會發生。 因此，在按鈕上，我使用代碼登錄然后發布，因為如果已經登錄，則跳過登錄。我遇到的問題是，登錄代碼在登錄代碼之后立即運行，因此在用戶輸入之前機會登錄。 這將導致打開2個彈出窗口（1個登錄名和1個帖子，其中顯示登錄名尚未登錄）。

我怎樣才能讓我的代碼等待用戶登錄，然后再轉到要發布的代碼的下一行？

FacebookHelper.h

@interface FacebookHelper : NSObject <FBSessionDelegate, FBRequestDelegate, FBDialogDelegate, FBLoginDialogDelegate> {
    Facebook *_facebook;
    NSArray *_permissions;
}

@property (nonatomic,strong) Facebook *facebook;

+(FacebookHelper *) sharedInstance;
+(void)fbDidLogin;

#pragma mark - Public Methods
-(BOOL) isFBSessionValid;
-(void) login;
-(void) logout;
-(void) postToWallWithDialogNewHighscore:(int)highscore;

@end

FacebookHelper.m

@implementation FacebookHelper
@synthesize facebook;

#pragma mark -
#pragma mark Singleton Variables
static FacebookHelper *singletonDelegate = nil;

#pragma mark -
#pragma mark Singleton Methods

+(FacebookHelper *)sharedInstance
{
    @synchronized(self) {
        if (singletonDelegate == nil) {
            singletonDelegate = [[self alloc] init]; // Assignment not done here
        }
    }
    return singletonDelegate;
}

-(id)init
{
    self = [super init];
    if (self) {
        _facebook = [[Facebook alloc] initWithAppId:kAppId andDelegate:self];
        // Restore previous session
        NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
        if ([defaults objectForKey:@"FBAccessTokenKey"] && [defaults objectForKey:@"FBExpirationDateKey"]) {
        _facebook.accessToken = [defaults objectForKey:@"FBAccessTokenKey"];
        _facebook.expirationDate = [defaults objectForKey:@"FBExpirationDateKey"];
        }
        //
    }
    return self;
}

+(id)allocWithZone:(NSZone *)zone
{
    @synchronized(self) {
        if (singletonDelegate == nil) {
            singletonDelegate = [super allocWithZone:zone];
            // assignment and return on first allocation
            return singletonDelegate;
        }
    }
    //on subsequent allocation attemps, return nil
    return nil;
}

-(id)copyWithZone:(NSZone *)zone
{
    return self;
}

#pragma mark - Facebook Delegate Methods

-(void)fbDidLogin
{
    NSLog(@"fbDidLogin");
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults setObject:[_facebook accessToken] forKey:@"FBAccessTokenKey"];
    [defaults setObject:[_facebook expirationDate] forKey:@"FBExpirationDateKey"];
    [defaults synchronize];
}

-(void)fbDidLogout
{
    NSLog(@"fbDidLogout");
    // Remove saved authorisation information if it exists
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    if ([defaults objectForKey:@"FBAccessTokenKey"]) {
        [defaults removeObjectForKey:@"FBAccessTokenKey"];
        [defaults removeObjectForKey:@"FBExpirationDateKey"];
        [defaults synchronize];
    }
}

#pragma mark - Public Methods

-(NSMutableDictionary *) buildPostParamsWithHighScore:(int)highscore
{
    NSString *customMessage = [NSString stringWithFormat:kCustomMessage, highscore, kAppName];
    NSString *postName = kAppName;
    NSString *serverLink = [NSString stringWithFormat:kServerLink];
    NSString *imageSrc = kImageScr;

    //Final params build
    NSMutableDictionary *params = [NSMutableDictionary dictionaryWithObjectsAndKeys:
                                   //@"message", @"message",
                                   imageSrc, @"picture",
                                   serverLink, @"link",
                                   postName, @"name",
                                   @" ", @"caption",
                                   customMessage, @"description",
                                   nil];
    return params;
}

-(BOOL) isFBSessionValid
{
    // Check if there is a valid session
    //_facebook = [[Facebook alloc] initWithAppId:kAppId andDelegate:self];
    _facebook.accessToken = [[NSUserDefaults standardUserDefaults] objectForKey:@"FBAccessTokenKey"];
    _facebook.expirationDate = [[NSUserDefaults standardUserDefaults] objectForKey:@"FBExpirationDateKey"];
    NSLog(@"accessToken=%@ expirationDaate=%@",_facebook.accessToken,_facebook.expirationDate);
    if (![_facebook isSessionValid]) {
        NSLog(@"FacebookHelper isFBSessionValid = NO");
        return NO;
    } else {
        NSLog(@"FacebookHelper isFBSessionValid = YES");
        return YES;
    }

    return NO;
}

-(void) login
{
    NSLog(@"FacebookHelper login");
    _permissions = [NSArray arrayWithObjects:@"publish_stream", nil]; //@"read_stream", @"offline_access"
    [_facebook authorize:_permissions];
}

-(void) logout
{
    [_facebook logout];
}

-(void) postToWallWithDialogNewHighscore:(int)highscore
{
    NSMutableDictionary *params = [self buildPostParamsWithHighScore:highscore];

    NSLog(@"Post Feed");
    [_facebook dialog:@"feed" andParams:params andDelegate:self];
}

@end

按鈕動作：

- (IBAction)facebookTest:(id)sender {
    [[FacebookHelper sharedInstance] login];
    [[FacebookHelper sharedInstance] postToWallWithDialogNewHighscore:123];
}

Answer 1

我更新了單例課程，將分數發布到Facebook Wall。 查看新版本： http : //indiedevstories.com/2012/04/11/facebookscorer-post-highscores-to-users-facebook-wall/

當需要授權和登錄時，此新版本可以正確處理內部狀態。

高溫超導

Answer 2

您需要做的是讓postToWallWithDialogNewHighscore調用登錄名（如果有必要），然后等待FBSession委托的回音。 然后，您需要設置您的facebook fbDidLogin委托，以便完成后將其發送回一條消息。 有多種方法可以執行此操作（登錄后選擇器，NSNotificationCenter等）。 這樣的事情應該可以工作（為方便起見，我假設我使用的是NSMutableDictionary * postParams的變量）：

-(void)doPost {
    NSLog(@"Post Feed");
    [_facebook dialog:@"feed" andParams:postParams andDelegate:self];
}

-(void)postToWallWithDialogNewHighscore:(int)highscore
{
    postParams = [self buildPostParamsWithHighScore:highscore];
    if (_facebook.isSessionValid) {
        [self doPost];
    } else {
        //register an observer for FB login messages
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(postToWallObserver:) name:@"FBLoginComplete" object:nil];
        [self login];
    }
}

-(void)fbDidLogin {
    NSLog(@"token granted until %@", [_facebook expirationDate]);
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults setObject:[_facebook accessToken] forKey:@"FBAccessTokenKey"];
    [defaults setObject:[_facebook expirationDate] forKey:@"FBExpirationDateKey"];
    [defaults synchronize];

    [[NSNotificationCenter defaultCenter] postNotificationName:@"FBLoginComplete" object:nil];    
}

-(void)fbDidNotLogin:(BOOL)cancelled {
    //do nothing as they didn't login   
}

-(void) postToWallObserver:(NSNotification *) notification {
    if ([[notification name] isEqualToString:@"FBLoginComplete"]) {
        if ([_facebook isSessionValid]) {
            [self doPost];
        } 
    }
    [[NSNotificationCenter defaultCenter] removeObserver:self];       
}

注意：我尚未編譯此代碼，因此可能會有錯別字等。