我正在使用FBSDKLoginManager在我的应用程序中实现Facebook登录.
Facebook docs似乎暗示这会为后续应用程序启动保存令牌,以便用户不必每次都登录：
The FBSDKLoginManager sets this token for you and when it sets currentAccessToken it also automatically writes it to a keychain cache.
我一直试图在应用程序启动时从所述缓存中检索此令牌,或者如果找不到则显示我的应用程序的Facebook登录屏幕：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[FBSDKProfile enableUpdatesOnAccessTokenChange:YES];
if ([FBSDKAccessToken currentAccessToken]) {
// user is logged in,continue to app's main screen
} else {
// show login screen
}
//...
}
解决方法
您需要调用“[[FBSDKApplicationDelegate sharedInstance]应用程序：application didFinishLaunchingWithOptions：launchOptions]”在尝试获取缓存令牌之前.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[[FBSDKApplicationDelegate sharedInstance] application:application didFinishLaunchingWithOptions:launchOptions];
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