部分申請代理從@callee_unowned

Question

咚幫手，我有以下斯威夫特功能：

func refresh(optionalHandler: @escaping (() -> Void) = {}) { 
    afnetworking.get(someURL, parameters: nil, successHandler: { 
    (task: URLSessionDataTask, object: Any) in 
     print(task) 
     optionalHandler() // This crashes with EXC_BAD_ACCESS 
    }) 
} 

不知道這裏發生了什麼......完整的錯誤是：

optionalHandler() ->() 0x000000010018baac MyApp`partial apply forwarder for reabstraction thunk helper from @callee_unowned @convention(block)() ->() to @callee_owned() ->() at MyViewController.swift 

Answer 1

大概在裏面afnetworking.get(someURL, parameters: nil, successHandler:您幾次撥打successHandler。

第二個電話optionalHandler()崩潰你的應用程序