ios – FacebookSDK提供两次登录UI

check for a valid FBSession.activeSession
if not open call FBSession openActiveSessionWithReadPermissions
if successful call FBSession.activeSession reauthorizeWithPublishPermissions
then publish post

我的理解是iOS 6需要双重登录才能获得ACAccountStore支持,因此Facebook login tutorial暗示您应该为所有情况执行此操作.将应用程序切换两次是糟糕的用户体验,我想我已经想出了@L_618_17@解决方案.

首先,对于较旧的iOS(例如iOS 5.0),您可以使用openActiveSessionWithPublishPermissions：并一次性执行读取和发布权限.其次,如果用户从未从“设备设置”登录Facebook,则此同一调用有效.因此,以下代码似乎工作如下：

>如果用户已从设备设置登录Facebook：@L_618_17@对话框
阅读和@L_618_17@发布对话框.
>如果用户安装了Facebook应用程序：
切换到FB应用程序一次,连续获得2个提示.
>否则：切换
到Safari一次,并连续获得2个提示

我使用Facebook SDK 3.2.1在iOS6和iOS5设备上测试了此代码

- (BOOL)hasFacebookInDeviceSetTings
{
    ACAccountStore *accountStore = [[ACAccountStore alloc] init];
    ACAccountType *accountTypeFB = [accountStore accountTypeWithAccountTypEIDentifier:@"com.apple.facebook"];
    BOOL hasFacebookBuilTinAccount = (accountTypeFB != nil);
    return hasFacebookBuilTinAccount;
}

- (BOOL)hasLoggedInToFacebookInDeviceSetTings
{
    if (![self hasFacebookInDeviceSetTings]) {
        return NO;
    }
    BOOL result = [SLComposeViewController isAvailableForserviCEType:SLserviCETypeFacebook];
    return result;
}

- (void)openFacebookSessionWithAllowLoginUI:(BOOL)allowLoginUI
{
    if (![self hasLoggedInToFacebookInDeviceSetTings]) {
        // Simpler if we don't have the built in account
        [FBSession openActiveSessionWithPublishPermissions:@[@"publish_actions"]
                                           defaultAudience:FBSessionDefaultAudienceFriends
                                              allowLoginUI:allowLoginUI
                                         completionHandler:^(FBSession *session,FBSessionState state,NSError *error) {
                                             [self facebookSessionStateChanged:session
                                                                         state:state
                                                                         error:error];
                                         }];
    }
    else if (!FBSession.activeSession.isOpen) {
        __block BOOL recursion = NO;
        [FBSession openActiveSessionWithReadPermissions:nil
                                           allowLoginUI:allowLoginUI
                                      completionHandler:^(FBSession *session,NSError *error) {
                                          if (recursion) {
                                              return;
                                          }
                                          recursion = YES;
                                          if (error || !FBSession.activeSession.isOpen) {
                                              [self facebookSessionStateChanged:session
                                                                          state:state
                                                                          error:error];
                                          }
                                          else {
                                              assert(FBSession.activeSession.isOpen);
                                              if ([FBSession.activeSession.permissions indexOfObject:@"publish_actions"] == NsnotFound) {
                                                  [FBSession.activeSession requestNewPublishPermissions:@[@"publish_actions"]
                                                                                        defaultAudience:FBSessionDefaultAudienceFriends
                                                                                      completionHandler:^(FBSession *session,NSError *error) {
                                                                                          [self facebookSessionStateChanged:session
                                                                                                                      state:FBSession.activeSession.state
                                                                                                                      error:error];
                                                                                      }];
                                              }
                                          }
                                      }];
    }
}

hasFacebookInDeviceSetTings告诉你这个设备是否甚至支持Facebook的设置(即这是iOS6).

hasLoggedInToFacebookInDeviceSetTings告诉您用户是否已从iOS6 Facebook设备设置登录到Facebook.

您需要创建自己的facebookSessionStateChanged：和其他代码,如login tutorial中所述