我想从方法(使用异步调用)返回一个数组(arr
)。我在该方法中实现了completionHandler
,但我无法使用我的方法获取我的阵列:Cast from '(@escaping ((Array<Any>) -> Void)) ->()' to unrelated type '[[String : Any]]' always fails
CompletionHandler在Swift 3中使用异步调用
我该如何解决这个问题?
这里是我的代码:
func dataWithURL(completion: @escaping ((_ result:Array<Any>) -> Void)) {
let urlString = "https://api.unsplash.com/photos/?client_id=71ad401443f49f22556bb6a31c09d62429323491356d2e829b23f8958fd108c4"
let url = URL(string: urlString)!
let urlRequest = URLRequest(url: url)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
var arr = [[String:String]]()
let task = session.dataTask(with: urlRequest, completionHandler: { (data, response, error) in
// do stuff with response, data & error here
if let statusesArray = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [[String: Any]] {
for item in statusesArray! {
let photos = item["urls"] as? [String: Any]
let photo = photos?["small"] as? String
let myDictionary = [
"name": "test",
"imageURL": photo]
arr.append(myDictionary as! [String : String])
}
print(arr)
completion(arr)
}
})
task.resume()
}
当我想要得到我的数组:
lazy var photos: [Photo] = {
var photos = [Photo]()
// HERE THE ERROR APPEARS
guard let data = self.dataWithURL as? [[String: Any]] else { return photos }
for info in data {
let photo = Photo(info: info)
photos.append(photo)
}
return photos
}()
我想你应该搜索如何调用函数,如何使用闭包,以及如何使用闭包作为完成块第一。 –