我已採取https://www.weheartswift.com/firebase-101/的原始代碼並進行編輯以適合我的需要。swift var不會在塊之外更新
在這個視圖控制器我更新一個圖像,然後,我用一個按鈕執行unwind segue和另一個視圖控制器調用函數updateValues並將數據存儲在firebase中。
什麼不工作是updateValues功能,但僅適用於taskImg值,其他(taskTitle和taskLat和taskLon完美的作品)
我認爲它不會更新,因爲它的這個代碼塊
#裏面self.storageRef.child(filePath).put(data as Data, metadata: metaData).observe(.success) { (snapshot) in
self.downloadURL = snapshot.metadata!.downloadURL()!.absoluteString
completion()
}
#
,因爲如果我嘗試任何var值從裏面改什麼也沒有發生,該塊它的工作原理之外,但obiouvsly我可以,因爲我沒有動態地生成它...
有人可以幫我嗎?
func editImage(completion: @escaping callback){
let resizedImage = resizeImage(image: imagePicked.image!, newWidth: 200)
var data = NSData()
// data = UIImageJPEGRepresentation(imagePicked.image!, 0.1)! as NSData
data = UIImageJPEGRepresentation(resizedImage!, 0.1)! as NSData
let filePath = "\(FIRAuth.auth()!.currentUser!.uid)/Pictures/\(NSUUID().uuidString)"
let metaData = FIRStorageMetadata()
//store downloadURL
metaData.contentType = "image/jpg"
self.storageRef.child(filePath).put(data as Data, metadata: metaData).observe(.success) { (snapshot) in
//progress upload
self.storageRef.child(filePath).put(data as Data, metadata: metaData).observe(.progress) { snapshot in
// Upload reported progress
if let progress = snapshot.progress {
let percentComplete = 100.0 * Double(progress.completedUnitCount)/Double(progress.totalUnitCount)
print("percent \(percentComplete)")
}
}
self.storageRef.child(filePath).put(data as Data, metadata: metaData).observe(.success) { snapshot in
// Upload completed successfully
print("success")
}
self.storageRef.child(filePath).put(data as Data, metadata: metaData).observe(.failure) { snapshot in
print(snapshot.error?.localizedDescription ?? "")
}
self.downloadURL = snapshot.metadata!.downloadURL()!.absoluteString
completion()
print(self.taskImg,"\"inside editImage function, right value")
}
}
func updateValues() {
self.taskTitle = self.titleField.text
if tapped == true {
self.taskLat = latitude
self.taskLon = longitude
}else{
//doesn't update location
}
self.taskCompleted = self.completedSwitch.isOn
if tappedpicture == true {
editImage { self.taskImg = self.downloadURL
print (self.downloadURL,"\"inside updateValues function, right value")
}
print (self.taskImg,"\"this is where i need it and it's wrong value")
}else{
//doesn't update location
}
}
什麼是self.taskImg的類型?請提供課程定義。 – iphaaw
self.taskImg的類型是字符串 – HaVaNa7
您應該將該塊視爲一個單獨的函數,在聲明的打印範圍超出範圍之後,在稍後的運行循環中調用該塊。我猜如果你在你的打印行上放置一個斷點,然後在你的任務上放置一個斷點(例如'self.taskImg = downloadURL'),你會看到'print'被首先調用。如果您在塊內分配後立即調用print,則會看到使用更新的值調用它。一旦它具有正確的值,你想用'taskImg'變量做什麼? –