Ios 如何在同一函数中仅为2个Alamofire请求提供1个完成处理程序
我有一个函数,里面有2个Alamofire请求和一个完成处理程序。一旦两个请求都从服务器下载完数据,我想重新加载collectionView。我在函数中有一个完成处理程序,但它会被调用两次,这会导致我的collectionView重新加载两次,我希望只重新加载一次。有没有办法让我这样做?非常感谢你Ios 如何在同一函数中仅为2个Alamofire请求提供1个完成处理程序,ios,swift,alamofire,completionhandler,Ios,Swift,Alamofire,Completionhandler,我有一个函数,里面有2个Alamofire请求和一个完成处理程序。一旦两个请求都从服务器下载完数据,我想重新加载collectionView。我在函数中有一个完成处理程序,但它会被调用两次,这会导致我的collectionView重新加载两次,我希望只重新加载一次。有没有办法让我这样做?非常感谢你 func getFeedVideos(completion: @escaping (_ completedDownloadVideo: Bool) -> ()){ Alamofire.
func getFeedVideos(completion: @escaping (_ completedDownloadVideo: Bool) -> ()){
Alamofire.request(youTubeUrl, method: .get, parameters: ["part":"snippet","maxResults": "20","nextPageToken" : "pageToken", "playlistId": playListId, "key": googleAPIKey], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(serverData.self, from: data)
self.dataFromAPI = json.items
completion(true)
} catch let jsonErr{
print(jsonErr)
}
}
Alamofire.request(youTubeChannelUrl, method: .get, parameters: ["part":"snippet", "key": googleAPIKey, "id": youTubeChannelId], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(channelInfo.self, from: data)
self.channelData = json.items
completion(true)
} catch let jsonErr{
print(jsonErr)
}
}
}
下面是我在ViewDidLoad中调用函数的方式
override func viewDidLoad() {
super.viewDidLoad()
getFeedVideos { (complete) in
if complete{
DispatchQueue.main.async {
self.collectionView?.reloadData()
}
}
}
}
更新您的
getFeedVideos
方法,如下所示:
func getFeedVideos(completion: @escaping (_ completedDownloadVideo: Bool) -> ()){
Alamofire.request(youTubeUrl, method: .get, parameters: ["part":"snippet","maxResults": "20","nextPageToken" : "pageToken", "playlistId": playListId, "key": googleAPIKey], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(serverData.self, from: data)
self.dataFromAPI = json.items
Alamofire.request(youTubeChannelUrl, method: .get, parameters: ["part":"snippet", "key": googleAPIKey, "id": youTubeChannelId], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(channelInfo.self, from: data)
self.channelData = json.items
completion(true)
} catch let jsonErr{
print(jsonErr)
}
}
} catch let jsonErr{
print(jsonErr)
}
}
}
正如我在您的代码中看到的,您在两个API调用中都调用了completion(true)
,这就是为什么它会多次重新加载。在我的代码中,我用另一个API调用替换了您的第一个API调用中的completion(true)
,因此一旦您的两个API调用都完成,您的completion(true)
将调用
希望这会有所帮助
注意:
没有在Xcode上检查此代码,因此如果您对此代码有任何问题,请告诉我。更好的解决方案
使用DispatchGroup
以下是示例
let dispatchGroup = DispatchGroup()
dispatchGroup.enter()
Alamofire.request(youTubeUrl, method: .get, parameters: ["part":"snippet","maxResults": "20","nextPageToken" : "pageToken", "playlistId": playListId, "key": googleAPIKey], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(serverData.self, from: data)
self.dataFromAPI = json.items
completion(true)
} catch let jsonErr{
print(jsonErr)
}
dispatchGroup.leave()
}
dispatchGroup.enter()
Alamofire.request(youTubeChannelUrl, method: .get, parameters: ["part":"snippet", "key": googleAPIKey, "id": youTubeChannelId], encoding: URLEncoding.default, headers: nil).responseJSON { (response) in
guard let data = response.data else {return}
do {
let json = try JSONDecoder().decode(channelInfo.self, from: data)
self.channelData = json.items
completion(true)
} catch let jsonErr{
print(jsonErr)
}
dispatchGroup.leave()
}
这是神奇的线条
dispatchGroup.notify(队列:.main){
打印(“两个功能都完成了!我只需要在第二次请求呼叫中输入self供参考。非常感谢!@kevinvu乐于帮助:)