等到异步api调用完成 – SwiftIOS

概述我正在开发一个ios应用程序,我的appDelegate中有： func application(application: UIApplication!, didFinishLaunchingWithOptions launchOptions: NSDictionary!) -> Bool { self.api.signInWithToken(emailstring, token: 我正在开发一个ios应用程序,我的appDelegate中有：

func application(application: UIApplication!,dIDFinishLaunchingWithOptions launchOptions: NSDictionary!) -> Bool {        self.API.signInWithToken(emailstring,token: authtokenstring) {        (object: AnyObject?,error:String?) in                        if(object != nil){                self.user = object as? User                // go straight to the home vIEw if auth succeeded                var rootVIEwController = self.window!.rootVIEwController as UINavigationController                let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main",bundle: nil)                var homeVIEwController = mainStoryboard.instantiateVIEwControllerWithIDentifIEr("HomeVIEwController") as HomeVIEwControllerenter                // code here                rootVIEwController.pushVIEwController(homeVIEwController,animated: true)            }        }    return true}

API.signInWithToken是一个用Alamofire进行的异步调用,我想在func应用程序的最后一端返回true之前等待它的完成.

解决方法

Note: You should not do it this way,as it blocks the thread. See Nate’s comment above for a better way.

有一种方法可以等待异步调用使用GCD完成.代码如下所示

var semaphore = dispatch_semaphore_create(0)performSomeAsyncTask {    ...    dispatch_semaphore_signal(semaphore)}dispatch_semaphore_wait(semaphore,disPATCH_TIME_FOREVER)dispatch_release(semaphore)

维基百科有一个OK article,如果您对信号量一无所知.

总结

以上是内存溢出为你收集整理的等到异步api调用完成 – Swift / IOS全部内容，希望文章能够帮你解决等到异步api调用完成 – Swift / IOS所遇到的程序开发问题。

如果觉得内存溢出网站内容还不错，欢迎将内存溢出网站推荐给程序员好友。