Flutter Channel Method String Not Working as URL - swift

Question

I have a Channel Method in my Flutter project which takes a String (url), downloads an image and presents it as part of a new contact.
However, the image won't be displayed for most urls.
This is the code I use to get the image and add to the new contact, before displaying it in a CNContactViewController.
let urlString : String = (arguments["imgUrl"] as? String)!
let url = URL(string: urlString)
let data = try? Data(contentsOf: url!)
newContact.imageData = data
I have tried encoding the url and casting it as an NSString with no luck.
Interesting, if I hard code the url in like below, it works. So what is happening between sending it from my Dart source code, over to Swift?
(URL modified to conceal contents, real URL returns image)
let url = URL(string: "https://23ee7ca4ch9430946b76-4f3bba1a032272305d39a357e474f3b2.ssl.cf1.rackcdn.com/talent/81843293_1556369106.jpeg")
let data = try? Data(contentsOf: url!)
newContact.imageData = data
Update:
Here is the full code...
Dart:
static const platform = const MethodChannel('contacts');
static Future<String> addSystemContact({
String firstName,
String lastName,
String jobTitle,
String company,
String phone,
String email,
String city,
String country,
String profile,
String imgUrl,
}) async {
try {
var result = await platform.invokeMethod(
'addSystemContact',
{
'firstName' : firstName != null && firstName.isNotEmpty ? firstName : "",
'lastName' : lastName != null && lastName.isNotEmpty ? lastName : "",
'jobTitle' : jobTitle,
'company' : company,
'phone' : phone,
'email' : email,
'city' : city,
'country' : country,
'profile' : profile,
'imgUrl': imgUrl,
},
);
return result;
} on PlatformException catch (e) {
return null;
}
}
Swift:
let controller : FlutterViewController = window?.rootViewController as! FlutterViewController
let contactChannel = FlutterMethodChannel(name: "contacts", binaryMessenger: controller)
contactChannel.setMethodCallHandler({(call: FlutterMethodCall, result: #escaping FlutterResult) -> Void in
//ADD SYSTEM CONTACT
//
if (call.method == "addSystemContact") {
let arguments : Dictionary = call.arguments as! Dictionary<String,Any>
guard let firstName : String = arguments["firstName"] as? String else { return result(false); }
guard let lastName : String = arguments["lastName"] as? String else { return result(false); }
//create contact
let newContact = CNMutableContact()
newContact.contactType = CNContactType.person
newContact.givenName = firstName
newContact.familyName = lastName
if let jobTitle : String = arguments["jobTitle"] as? String {
newContact.jobTitle = jobTitle
}
if let company : String = arguments["company"] as? String {
newContact.organizationName = company
}
if let phone : String = arguments["phone"] as? String {
newContact.phoneNumbers = [CNLabeledValue(
label:CNLabelPhoneNumberMain,
value:CNPhoneNumber(stringValue:phone))]
}
if let email : NSString = arguments["email"] as? NSString {
newContact.emailAddresses = [CNLabeledValue(label:CNLabelWork, value:email)]
}
let address = CNMutablePostalAddress()
if let city : String = arguments["city"] as? String {
address.city = city
}
if let country : String = arguments["country"] as? String {
address.country = country
}
newContact.postalAddresses = [CNLabeledValue(label:CNLabelWork, value:address)]
if let profile : String = arguments["profile"] as? String {
newContact.socialProfiles = [CNLabeledValue(label:
CNSocialProfileServiceLinkedIn, value: CNSocialProfile.init(urlString: profile, username: nil, userIdentifier: nil, service: nil))]
}
// Offending code...
//
let urlString : String = (arguments["imgUrl"] as? String)!
let url = URL(string: urlString)
let data = try? Data(contentsOf: url!)
newContact.imageData = data
//
//
//presents nav controller with CNContactViewController
self.displayConactViewController(newContact: newContact, result: result)
}
})

Answer 1

You seem to have a mix of methodologies. Are you passing a single string as the argument, or a map? Unfortunately you don't show the Dart end.
Here are some working examples, adapted from a working plugin.
Single String
Dart end
static void ping(String pong) {
_channel.invokeMethod('ping', pong);
}
Swift end - call.arguments is a String
case "ping":
NSLog("ping")
if let pong = call.arguments as! String {
// do something
} else {
NSLog("ping - Invalid Args")
}
break
String as map member
Dart end
static void foo(String bar, String baz) {
_channel.invokeMethod('foo', <String, dynamic>{
'bar': bar,
'baz': baz,
});
}
Swift end - call.arguments is a Dictionary
case "foo":
NSLog("foo")
if let args = call.arguments as? Dictionary<String, Any>, let bar = args["bar"] as! String {
// do something with bar and/or args["baz"] as! String
} else {
NSLog("foo - Args is not a Dictionary")
}
break