Async pattern using new concurrency model in swift that can be applied to Core Bluetooth, Core Motion and others sources streaming data asynchronously
if you are using the simulator don't forget to simulate locations
- Using new concurrency swift model around CoreLocation manager
- Customizable in terms of passing a custom delegate(CLLocationManagerDelegate) conforming to ILocationDelegate protocol
- Customizable in terms of CLLocationManager properties
- Streaming current location asynchronously
- Different strategies - Keep and publish all stack of locations since streaming has started or the last one
- Support for iOS from 14.1 and watchOS from 7.0
- Errors handling (as AsyncLocationErrors so CoreLocation errors CLError)
@EnvironmentObject var model: LMViewModel
If task will be canceled the streaming stops automatically. I would recommend to use .task modifier it manages cancelation on it's own. If you need to use Task and keep it in @State don't forget to cancel() when the time has come or it might course memory leaks in some cases
.task{
do{
try await viewModel.start()
}catch{
self.error = error.localizedDescription
}
}
@ViewBuilder
var coordinatesTpl: some View{
List(viewModel.locations, id: \.hash) { location in
Text("\(location.coordinate.longitude), \(location.coordinate.latitude)")
}
}
///Access was denied by user
case accessIsNotAuthorized
/// Attempt to launch streaming while it's been already started
/// Subscribe different Views to LMViewModel.locations publisher to feed them
case streamingProcessHasAlreadyStarted
/// Stream was cancelled
case streamCanceled
/// Stream was terminated
case streamUnknownTermination
/// A Core Location error
case coreLocationManagerError(CLError)
There's been a glitch - throwing CLError.locationUnknown Error Domain=kCLErrorDomain Code=0 "(null)" on some devices and simulator while changing locations time by time. This type of error .locationUnknown is excluded when it happens in the delegate method didFailWithError
public protocol ILocationManagerViewModel: ObservableObject{
/// List of locations
@MainActor
var locations : [CLLocation] { get }
/// Strategy for publishing locations Default value is .keepLast
/// .keepAll is an option
var strategy : LMViewModel.Strategy { get }
/// Start streaming locations
func start() async throws
/// Stop streaming locations
func stop()
}
| Param | Description |
|---|---|
| strategy | Strategy for publishing locations Default value is .keepLast The other option is .keepAll |
| accuracy | The accuracy of a geographical coordinate. |
| activityType | Constants indicating the type of activity associated with location updates. |
| distanceFilter | A distance in meters from an existing location. |
| backgroundUpdates | A Boolean value that indicates whether the app receives location updates when running in the background |
- Product > Scheme > Edit Scheme
- Click Run .app
- Option tab
- Already checked Core Location > select your location
- Press OK
Available for watchOS
- You need to have Xcode 13 installed in order to have access to Documentation Compiler (DocC)
- Go to Product > Build Documentation or ⌃⇧⌘ D