I've checked the syntax a gazillion times here, on GitHub, parse.com & elsewhere, without any luck. The problem is when I'm calling saveInBackgroundWithBlock for PFObject I get the the following error:
Cannot invoke 'saveInBackgroundWithBlock' with an argument list of type '((Bool, NSError) -> Void)'
I'm on Xcode 6.3 beta 2. All frameworks are loaded to the project (including Bolts & Parse, but not provided by parse.com ParseCrashReporting & ParseUI), <Parse/Parse.h> & even <Bolts/Bolts.h> are brought through the Bridge Header.
var score = PFObject(className: "score")
score.setObject("Rob", forKey: "name")
score.setObject(95, forKey: "scoreNumber")
score.saveInBackgroundWithBlock {
(success: Bool!, error: NSError) -> Void in
if success == true {
println("Score created with ID: \(score.objectId)")
} else {
println(error)
}
}
Any thoughts?
The error parameter is supposed to be an implicitly unwrapped optional, but not the success one:
(success: Bool, error: NSError!) -> Void in
^ ^
However unless you need to specify the type for whatever reason, I suggest you to use the closure simply as:
(success, error) in
less prone to type declaration errors.
In Swift 1.2 the declaration of .saveInBackgroundWithBlock should look like this:
Void saveInBackgroundWithBlock(block: PFBooleanResultBlock?(Bool, NSError?) -> Void)
So it should have been as follows:
score.saveInBackgroundWithBlock {
(success: Bool, error: NSError?) -> Void in
The method wants the success and error variables set like this with the ! on the error:
(success: Bool, error: NSError!)
^ ^
But you've set the ! to the wrong variable:
(success: Bool!, error: NSError)
As you see here:
Related
I have the following code snippet.
camera.onDeviceChange = { [weak self] (camera: LLSimpleCamera!, device: AVCaptureDevice!) -> Void in
print("Device changed.")
}
This used to work fine in Swift 2, but now I am getting the following error message:
Cannot assign value of type '(LLSimpleCamera!, AVCaptureDevice!) -> Void' to type '((LLSimpleCamera?, AVCaptureDevice?) -> Void)!'
Not really sure how to change this, I tried matching the type by changing the ! to optionals and then adding ! after the void, however this didn't work.
Your error suggest type mismatch that means LLSimpleCamera! != LLSimpleCamera? .. there is no need to define type. .. you can use it something like
camera.onDeviceChange = { [weak self] (camera, device) -> Void in
print("Device changed.")
}
I converted my project to swift 3 and am having issue with the kinvey conversion. I had this before but it now gives me this error: "Cannot convert value of type '(AnyObject!, NSError!) -> Void' to expected argument type 'KCSCustomEndpointBlock!'". How could I fix this issue?
KCSCustomEndpoints.callEndpoint("endpointName", params: params, completionBlock: {
(results: AnyObject!, error: NSError!) -> Void in
if results != nil {
}
})
Mitch94,
This has been escalated to the engineering team for adding Swift 3 example of invoking custom endpoint to the Kinvey documentation.
I will get back to you once I have more information on it.
Thanks,
Pranav
Kinvey Support
I have working project in Xcode 7.3 with swift 2.2 version. Now I have updated Xcode 8 and migrated to swift 3. Now my project contains errors specially for blocks like success block of afnetworking.
Which gives error as
Cannot convert value of type '() -> ()' to expected argument type '((URLSessionDataTask, Any?) -> Void)?'
I don't understand how to solve this to work as per swift 3.
And there is also same like error in Facebook login.
Which gives error as
Cannot convert value of type '(FBSDKLoginManagerLoginResult!, NSError!) -> Void' to expected argument type 'FBSDKLoginManagerRequestTokenHandler!'
and
Cannot convert value of type '(_, _, NSError!) -> Void' to expected argument type 'FBSDKGraphRequestHandler!'
This all errors are related to handler blocks in swift 3. I don't understand the errors and so that can't able to solve. Any help will be appreciated. Thanks in advance.
For facebook - the problem is in new Swift rules about converting objective-c function parameters into Swift.
Previously, if parameters in objective-c code did not have nullability attributes(like nonnull or nullable), Swift converts it with ! making them non optional(forced unwrapping). Now it convert it with ? making them optional. That why you are getting an error. Before you were putting as a callback for login:
(FBSDKLoginManagerLoginResult!, NSError!) -> Void
Now you need to put:
(FBSDKLoginManagerLoginResult?, Error?) -> Void
Also, as you see, now you will not see NSError class. Instead of that Swift will put Error.This is also new rule. Now all "NS" prefixed in class names is removed in Swift(NSObject -> Object; NSError -> Error).
Example of working code for facebook login in Swift 3.0:
let manager = FBSDKLoginManager()
manager.logIn(withReadPermissions: ["public_profile"], from: self.controller) {
(loginResult: FBSDKLoginManagerLoginResult?, error: Error?) in
}
Example of working code for facebook request in Swift 3.0:
let request = FBSDKGraphRequest()
request.start {
(connection: FBSDKGraphRequestConnection?, result: Any?, error: Error?) in
}
As you see, now it is using Any type instead of objective-c id. In Swift 2.2 it was using AnyObject. It is also new Swift converting rule.
You do not need to specify callback parameters type. I did that in code for highlighting their real types. So you can just write code without them:
let manager = FBSDKLoginManager()
manager.logIn(withReadPermissions: ["public_profile"], from: self.controller) { (loginResult, error) in }
let request = FBSDKGraphRequest()
request.start { (connection, result, error) in }
But you need to remember that they are optional now.
In conclusion some converting rules that may affect you callback code:
Closure parameters are optional if in objective-c are not specified nullability attributes
All "NS" prefixes is removed for objective-c classes in Swift
If objective-c function had id parameter, in Swift 3.0 it will have type Any instead of AnyObject
Though I didn't know the error before that what Xcode want to inform me about the error, but I have removed type specification with object and it worked.
As
manager.post(methodname, parameters: param, progress: nil, success:{ (dataTask, responseObj) in
if let dict : NSDictionary = responseObj as? NSDictionary {
print("Response of \(methodname) : \(dict)")
if dict.object(forKey: "response") as? String == "success" {
CompletionHandler(true, dict)
} else {
CompletionHandler(false, dict)
}
}
})
Here with respect to question error is given at dataTask and responseObj which are with type specified. After removing type it worked fine.
Same as with facebook login
#IBAction func fbLoginClicked(_ sender: AnyObject) {
let app = UIApplication.shared.delegate as! AppDelegate
app.fbLoginManager = FBSDKLoginManager()
app.fbLoginManager.logOut()
app.fbLoginManager.loginBehavior = FBSDKLoginBehavior.native
app.fbLoginManager.logIn(withReadPermissions: ["email"], from: self, handler: { (result, error) -> Void in
if error != nil {
print(error?.localizedDescription)
} else {
if (result! as FBSDKLoginManagerLoginResult).isCancelled == true {
} else {
self.fetchFacebookUserDetail()
}
}
})
}
Here also I have removed type specification of result and error and problem solved. And followed this in whole app and it worked. I can run the project without error and also it is working. Thanks.
So I'm just trying to set up my new app with parse. I've downloaded their SDK and I've pasted my applicationID. The problem is in push notifications (which I didn't even touch). Can someone please help me?
Thanks
ERROR CODE:
PFPush.subscribeToChannelInBackground("") { (succeeded: Bool, error: NSError?) in
if succeeded {
print("ParseStarterProject successfully subscribed to push notifications on the broadcast channel.\n");
} else {
print("ParseStarterProject failed to subscribe to push notifications on the broadcast channel with error = %#.\n", error)
}
}
}
It says:
Cannot invoke 'subscribeToChannelInBackground' with an argument list
of type '(String, (Bool, NSError?) -> ())'
The code you are showing is to subscribe to notification channel...and it is complaining that it doesn't expect these arguments type.
To set up Parse SDK follow this: https://www.parse.com/apps/quickstart#parse_data/mobile/ios/swift/existing
from the parse getting started guide, this is how they tested the installation was good to go (swift)
let testObject = PFObject(className: "TestObject")
testObject["foo"] = "bar"
testObject.saveInBackgroundWithBlock { (success: Bool, error: NSError?) -> Void in
print("Object has been saved.")
}
Clearly the syntax of the function call is wrong. Follow the function (right click on the function in Xcode and "Jump to definition") to find out which arguments exactly the function expects. I don't know the SDK, but I guess the function takes two arguments - a string and a closure (block). Then you need to use that in your call instead of whatever you are using now.
I just updated to beta 5 of XCode 7 and am now getting a compliation error on the following Swift code:
MagicalRecord.saveWithBlock({ (localContext : NSManagedObjectContext!) in
// ... Save models here ...
}, completion: { (success : Bool, error : NSError!) in
// ... Handle completion here ...
})
Under previous builds of XCode 7, this compiled fine, but I'm now getting:
Cannot invoke 'saveWithBlock' with an argument list of type '((NSManagedObjectContext!) -> (), completion: (Bool, NSError!) -> ())'
I've tried adding -> Void (as autocompleted when I try to add the call afresh) and -> Void! to the parameters, but see the same error.
Is this a language change or a bug in this XCode build?
EDIT (5.42pm ETC 08/08/2015): Calling savedWithBlock without the completion handler appears to compile ok:
MagicalRecord.saveWithBlock { (localContext: NSManagedObjectContext!) -> Void in
// ... Save models here ...
}
EDIT (8.32am ETC 08/11/2015): Following recommendation by #Gerd Castan, I also tried changing the completion parameter to:
completion: { (success : Bool, error : ErrorType!)
and
completion: { (success : ObjCBool, error : ErrorType!)
Both of which gave the same error.
This appears to be fixed with XCode 7 Beta 6. The syntax:
MagicalRecord.saveWithBlock({ (localContext: NSManagedObjectContext!) -> Void in
// Save model here
}) { (success: Bool, error: NSError!) -> Void in
// Handle result here
}
Compiles without error.
Apple replaced NSError with ErrorType.
Replace your own explicit usage of NSError with ErrorType to avoid this type of compiler errors.