Swift prints all network error descriptions in console (from the enum CFNetworkErrors?).
But I want to get access to the enum in app so that I can keep track of what error I am getting while the app loads.
I'm following the MVC pattern and tried to get access to errors in my "Model" section. Still I didn't get it right. This is what I did inside dataTask in the class where I load the APIs:
if self.networkErrors != nil {
print(self.networkErrors.debugDescription)
}
where I declared: var networkErrors: CFNetworkErrors?
Do I need to put the cases to check or there is some other way to catch the errors printed in console as in the image?
Console Screenshot
You could access the error code through this simple approach
if self.networkErrors != nil {
print(self.networkErrors.debugDescription)
print(self.networkErrors._code) // This will print the error code.
}
Related
This question already has answers here:
Returning data from async call in Swift function
(13 answers)
Closed last year.
I am building a mobile app with swift, and am having some syntax issues as I am not a developer. The structure and logic of the application is really rough and surely incorrect, however we just need something that functions. (It is a school project and my team got no devs).
Anyways, we have a MySQL database that will be used as a middleman between our badge server/admin app, and our mobile app. Currently when you go to https://gatekeeperapp.org/service.php , you will see the current database data, taken by a php script and hosted there as JSON. Currently in Swift I have a struct with a function that takes this JSON data, and maps it to variables. The idea is to then pass these pulled variables into a separate set of functions that will check the pulled long/lat against the mobile devices location, and then return whether they match or not. This value would be updated, re-encoded to JSON, and pushed to a web service that would go about changing the values in the database so the badge server could use them.
Where I am currently I can see that values are being pulled and mapped and I can set a variable in a separate function to the pulled value, but then I can only seem to output this value internally, rather than actually use it in the function. I get a type error saying that the pulled values are of type (). How can I properly use these values? Ultimately I think I would want to convert the () to a double, so I could properly compare it to the Long/Lat of the device, and then will need to re-encode the new values to JSON.
Swift Code -- struct function
Swift code -- JSON struct
Swift code -- using pulled data
Your closure is called asynchronously, which means that the outer function where you are expecting to use the values has already returned by the time the closure is called. Instead, you probably need to call some other function from the closure, passing the values you've received.
class MyClass {
func fetchUserData() {
UserData().fetchUser { [weak self] user, error in
DispatchQueue.main.async {
if let user = user {
self?.handleSuccess(userID: user)
} else if let error = error {
self?.handleError(error)
}
}
}
}
private func handleSuccess(userID: String) {
print(userID)
// Do something with userID. Maybe assign it to a property on the class?
}
private func handleError(_ error: Error) {
print(error)
// Handle the error. Maybe show an alert?
}
}
So my goal is to get rid of these bugs completely. I am in a dilemma where each decision leads to a bug.
The first thing I can do that eventually becomes an issue is use a String-interpolated collection path in all my query functions like so:
func getEventName() {
listener = db.collection("school_users/\(user?.uid)/events").order(by: "time_created", descending: true).addSnapshotListener(includeMetadataChanges: true) { (querySnapshot, error) in
if let error = error {
print("There was an error fetching the data: \(error)")
} else {
self.events = querySnapshot!.documents.map { document in
return EventName(eventName: (document.get("event_name") as! String))
}
self.tableView.reloadData()
}
}
}
The thing with this is, when I run the app on the simulator, I am restricted from pressing buttons and then sometimes I can press them and then sometimes they get restricted again. This bug is so confusing because it makes no sense where it springs from.
The other issue is I can use a Constants value in all the query functions in my collections path.
static let schoolCollectionName = "school_users/\(user?.uid)/events"
This is nested in a Firebase struct within the Constants struct. In order to keep Xcode from giving errors I create a let users = Auth.auth().currentUser variable outside the Constants struct. The issue with this value is that when I put that in all of my query functions collection paths, all the buttons are accessible and selectable all the time, but when a user logs out and I log in as a new user, the previous user's data shows up in the new user's tableview.
It would obviously make more sense to use the Constants value because you prevent typos in the future, but I can't figure out how to get rid of the bug where the old user's data shows up in the new user's tableview. Thanks in advance.
The user id should definitely not be a constant. What it sounds like is that right now, you have no reliable way to change users -- your setup probably depends on which user is logged in at app startup, since that's where your variable gets set.
I would do something more like this:
func getEventName() {
guard let user = Auth.auth().currentUser else {
//handle the fact that you don't have a user here -- don't go on to the next query
return
}
listener = db.collection("school_users/\(user.uid)/events").order(by: "time_created", descending: true).addSnapshotListener(includeMetadataChanges: true) { (querySnapshot, error) in
Note that now, user.uid in the interpolated path doesn't have the ? for optionally unwrapping it (which Xcode is giving you a warning for right now). It will also guarantee that the correct query is always made with the currently-logged-in user.
Regarding being able to press the buttons, that sounds like an unrelated issue. You could run your app in Instruments and check the Time Profiler to see if you have long-running tasks that are gumming up the main/UI thread.
I am getting this error when trying to use the sample code from Google Places getting started Link
Error: Current Place error: The operation couldn’t be completed. An internal error occurred in the Places API library.
I am calling this function on viewDidLoad. I also created a IBAction with this code to make sure it wasn't a timing issue. I got the same error this way as well.
placesClient.currentPlace { (placeLikelihoods, error) in
guard error == nil else {
print("Current Place error: \(error!.localizedDescription)")
return
}
if let placeLikelihoods = placeLikelihoods {
for likelihood in placeLikelihoods.likelihoods {
let place = likelihood.place
print(place.name)
}
}
}
I have created a new project in Firebase, which created a new project in Google Dev Console. I created new API Key, Enabled Google Maps and Google Places API. I added CoreLocation framework, my pods are up to date. I should not be hitting any limits as it is just me learning. I have the Location When In Use set up i the Plist - user gets the dialog on fresh install. I accepted it. I added location manager code from here to make sure I am getting the location. I signed up for Apple developer to get the app on my device just in case the location wasn't staying on the simulator. I have a feeling this is something stupid. Please let me know any ideas to get passed this. Thanks!
I use SKProductsRequest to download product infos from App Store.
When I test a connectivity loss on my device, the request fails, but my app crashes within the SKRequestDelegate when I try to NSLog the error:
What am I doing wrong ? Another curious thing to me is that Expression Inspector is able to display NSError.debugDescription...
It fails on the first request, so there is no possible bug relative to multiple uses of productRequest variable (which is a strong ref in my swift class).
I finally found the reason. It is not related to SKProductsRequest!
I think there is a nasty bug with NSLogand string interpolation because when I replace:
NSLog("Failed: \(error.debugDescription)")
by
print("Failed: \(error.debugDescription)")
all is fine!
Apparently, the content of the error message can provoke a EXC_BAD_ADDRESS in NSLog (even without string interpolation in fact: NSLog(error.debugDescription) fails too).
Related anwser: https://stackoverflow.com/a/29631505/249742
NSLog("%#", error.debugDescription)
seems to work fine in every cases.
Perhaps NSLog(variable) is a misuse of NSLog, but I think NSLog(\(variable)) should be interpreted like NSLog("%#", variable). Else, there is no reliable way to interpolate strings with NSLog using the swift way \().
Im trying to query my Parse User database in order to create a friend request between two users. The user inputs a user name that they want to add as a friend. However, when I try to query the database, I get a "EXC_BAD_ACCESS" error on the line where I am adding the condition. Not sure why Im getting this error, as its my understanding it has to do with trying to access memory already freed. Anything that you can do to help would be very appreciated!
var friendship = PFObject(className: "Friends")
var findUser:PFQuery = PFUser.query()
findUser.whereKey("username",equalTo:username2) //program crashes here for some reason
findUser.getFirstObjectInBackgroundWithBlock {
(user2, error: NSError!) -> Void in
if user2 == nil {
println("Failure")
} else {
println("Successfully retrieved the object.")
friendship["user1"] = PFUser.currentUser().objectId
friendship["user2"] = user2.objectId
friendship["pending"] = true
friendship.save()
}
}
Set a breakpoint in the compiler and navigate the steps until you hit the crash so you can understand exactly at which point it crashes a troubleshoot further from there with the better understanding.
Also once it has crashed use LLDB print out po ivar to check if any of your ivars got instantiated and which ones are empty or execute dubious functions with exp func.
So... It works today. Not sure what happened. Co-Developer and I reorganized frameworks and everything works fine now. Thank you for your help everyone. I appreciate the responses :)