swift uploadTaskWithRequest with didReceiveData - swift

Question

I am pretty new to swift i have the following code
var data : AnyObject
let dict = jsonObject as NSDictionary
do
{
data = try NSJSONSerialization.dataWithJSONObject(dict, options:.PrettyPrinted)
let strData = NSString(data: data as! NSData, encoding: NSUTF8StringEncoding)! as String
data = strData.dataUsingEncoding(NSUTF8StringEncoding)!
let task = defaultSession.uploadTaskWithRequest(request, fromData: data as? NSData,
completionHandler:
{(data,response,error) in
guard let _:NSData = data, let _:NSURLResponse = response where error == nil
else {
return
}
});
task.resume()
}catch{
return resultJson
}
the resultJson object returns a empty array as there are more date to be downloaded and it takes time.I am wondering weather i can use didReceiveData option to return data after it is downloaded. I searched for code online but couldn't find any. Any help with code is much appreciated.
Thanks

Answer 1

You're right in that the return will run before the upload is finished, and therefore you won't get the desired result. I assume this code is in a function. You need to change it to take a closure as a parameter. Then when the upload is finished, you call that closure. Something like:
func doTheUpload(completion completionHandler: ((AnyObject?) -> Void)) {
var data : AnyObject
let dict = jsonObject as NSDictionary
do
{
data = try NSJSONSerialization.dataWithJSONObject(dict, options:.PrettyPrinted)
let strData = NSString(data: data as! NSData, encoding: NSUTF8StringEncoding)! as String
data = strData.dataUsingEncoding(NSUTF8StringEncoding)!
let task = defaultSession.uploadTaskWithRequest(request, fromData: data as? NSData,
completionHandler:
{(data,response,error) in
guard let _:NSData = data, let _:NSURLResponse = response where error == nil
completionhandler(resultJson)
else {
return
}
});
task.resume()
}catch{
// Do something for error
}
}
Then you would call it as:
doTheUpload(completion: {
resultJson in
// use the result
})
Note that I don't know where you're getting resultJson from or what type it is, so you will have to make some changes.