How to pass potential error between methods

I'm trying to wrap Core Bluetooth Peripheral methods for use in React Native. It's a counterpart for already finished android code, so the API is set.

When I'm calling CBPeripheralManager.addService, I need to fulfill or reject a promise, handed from the javascript side.

The problem is, Core Bluetooth doesn't offer a callback for the method, it seems to expect private func peripheralManager(_ peripheral: CBPeripheralManager, didAddService service: CBService, error: Error?)

I'm new to iOS and Swift so this behavior seems strange to me. Any ideas how can I wrap the function so I can handle the error reporting properly?

Thanks

class BLE: NSObject, CBPeripheralManagerDelegate {

    var advertising: Bool = false

    var servicesMap = Dictionary<String, CBMutableService>()

    var manager: CBPeripheralManager!



    override init() {

        super.init()

        manager = CBPeripheralManager(delegate: self, queue: nil, options: nil)

    }



    func addService(promise, serviceUUID) {

        let serviceUUID = CBUUID(string: uuid)

        let service = CBMutableService(type: serviceUUID, primary: true)

        manager.add(service)

    }



    private func peripheralManager(_ peripheral: CBPeripheralManager, didAddService service: CBService, error: Error?) {

        if let error = error {

            // this should reject the addService promise

            return

        }

        // this should fulfill the promise

    }    

}

asked Jan 3 at 0:28

Eskel

4801317

What do you want it to do when the error happens, exactly? Whatever that is, just do it inside the if let block (or call a function from there to handle it and pass the error as a parameter).

– John Montgomery
Jan 3 at 0:34

1

This delegate method is incorrect, and is probably never called. The correct method would be func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?), and it can't be a private method. The addService() method also isn't valid, but in any case, you would need to store the promise somewhere so you can later fulfill it.

– Rob Napier
Jan 3 at 1:15

OK, thanks. But I'm confused, the CBPeripheralManagerDelegate class doesn't have access to it's private functions?

– Eskel
Jan 3 at 19:16

1

The class has access to its own private methods, but CBPeripheralManager doesn't have access to its delegate's private methods. It's the manager that calls this method, not the delegate.

– Rob Napier
Jan 3 at 19:24

1

@Eskel Correct. That's the name of the signature I wrote: func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?). The name of that is peripheralManager(_:didAdd:error:).

– Rob Napier
Jan 4 at 21:46

|
show 1 more comment

I'm trying to wrap Core Bluetooth Peripheral methods for use in React Native. It's a counterpart for already finished android code, so the API is set.

When I'm calling CBPeripheralManager.addService, I need to fulfill or reject a promise, handed from the javascript side.

I'm new to iOS and Swift so this behavior seems strange to me. Any ideas how can I wrap the function so I can handle the error reporting properly?

Thanks

class BLE: NSObject, CBPeripheralManagerDelegate {

    var advertising: Bool = false

    var servicesMap = Dictionary<String, CBMutableService>()

    var manager: CBPeripheralManager!



    override init() {

        super.init()

        manager = CBPeripheralManager(delegate: self, queue: nil, options: nil)

    }



    func addService(promise, serviceUUID) {

        let serviceUUID = CBUUID(string: uuid)

        let service = CBMutableService(type: serviceUUID, primary: true)

        manager.add(service)

    }



    private func peripheralManager(_ peripheral: CBPeripheralManager, didAddService service: CBService, error: Error?) {

        if let error = error {

            // this should reject the addService promise

            return

        }

        // this should fulfill the promise

    }    

}

asked Jan 3 at 0:28

Eskel

4801317

What do you want it to do when the error happens, exactly? Whatever that is, just do it inside the if let block (or call a function from there to handle it and pass the error as a parameter).

– John Montgomery
Jan 3 at 0:34

1

This delegate method is incorrect, and is probably never called. The correct method would be func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?), and it can't be a private method. The addService() method also isn't valid, but in any case, you would need to store the promise somewhere so you can later fulfill it.

– Rob Napier
Jan 3 at 1:15

OK, thanks. But I'm confused, the CBPeripheralManagerDelegate class doesn't have access to it's private functions?

– Eskel
Jan 3 at 19:16

1

The class has access to its own private methods, but CBPeripheralManager doesn't have access to its delegate's private methods. It's the manager that calls this method, not the delegate.

– Rob Napier
Jan 3 at 19:24

1

@Eskel Correct. That's the name of the signature I wrote: func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?). The name of that is peripheralManager(_:didAdd:error:).

– Rob Napier
Jan 4 at 21:46

|
show 1 more comment

I'm trying to wrap Core Bluetooth Peripheral methods for use in React Native. It's a counterpart for already finished android code, so the API is set.

When I'm calling CBPeripheralManager.addService, I need to fulfill or reject a promise, handed from the javascript side.

I'm new to iOS and Swift so this behavior seems strange to me. Any ideas how can I wrap the function so I can handle the error reporting properly?

Thanks

class BLE: NSObject, CBPeripheralManagerDelegate {

    var advertising: Bool = false

    var servicesMap = Dictionary<String, CBMutableService>()

    var manager: CBPeripheralManager!



    override init() {

        super.init()

        manager = CBPeripheralManager(delegate: self, queue: nil, options: nil)

    }



    func addService(promise, serviceUUID) {

        let serviceUUID = CBUUID(string: uuid)

        let service = CBMutableService(type: serviceUUID, primary: true)

        manager.add(service)

    }



    private func peripheralManager(_ peripheral: CBPeripheralManager, didAddService service: CBService, error: Error?) {

        if let error = error {

            // this should reject the addService promise

            return

        }

        // this should fulfill the promise

    }    

}

asked Jan 3 at 0:28

Eskel

4801317

I'm trying to wrap Core Bluetooth Peripheral methods for use in React Native. It's a counterpart for already finished android code, so the API is set.

When I'm calling CBPeripheralManager.addService, I need to fulfill or reject a promise, handed from the javascript side.

I'm new to iOS and Swift so this behavior seems strange to me. Any ideas how can I wrap the function so I can handle the error reporting properly?

Thanks

class BLE: NSObject, CBPeripheralManagerDelegate {

    var advertising: Bool = false

    var servicesMap = Dictionary<String, CBMutableService>()

    var manager: CBPeripheralManager!



    override init() {

        super.init()

        manager = CBPeripheralManager(delegate: self, queue: nil, options: nil)

    }



    func addService(promise, serviceUUID) {

        let serviceUUID = CBUUID(string: uuid)

        let service = CBMutableService(type: serviceUUID, primary: true)

        manager.add(service)

    }



    private func peripheralManager(_ peripheral: CBPeripheralManager, didAddService service: CBService, error: Error?) {

        if let error = error {

            // this should reject the addService promise

            return

        }

        // this should fulfill the promise

    }    

}

swift core-bluetooth

asked Jan 3 at 0:28

Eskel

4801317

asked Jan 3 at 0:28

Eskel

4801317

asked Jan 3 at 0:28

Eskel

4801317

asked Jan 3 at 0:28

Eskel

4801317

asked Jan 3 at 0:28

Eskel

4801317

What do you want it to do when the error happens, exactly? Whatever that is, just do it inside the if let block (or call a function from there to handle it and pass the error as a parameter).

– John Montgomery
Jan 3 at 0:34

1

This delegate method is incorrect, and is probably never called. The correct method would be func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?), and it can't be a private method. The addService() method also isn't valid, but in any case, you would need to store the promise somewhere so you can later fulfill it.

– Rob Napier
Jan 3 at 1:15

OK, thanks. But I'm confused, the CBPeripheralManagerDelegate class doesn't have access to it's private functions?

– Eskel
Jan 3 at 19:16

1

The class has access to its own private methods, but CBPeripheralManager doesn't have access to its delegate's private methods. It's the manager that calls this method, not the delegate.

– Rob Napier
Jan 3 at 19:24

1

@Eskel Correct. That's the name of the signature I wrote: func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?). The name of that is peripheralManager(_:didAdd:error:).

– Rob Napier
Jan 4 at 21:46

|
show 1 more comment

What do you want it to do when the error happens, exactly? Whatever that is, just do it inside the if let block (or call a function from there to handle it and pass the error as a parameter).

– John Montgomery
Jan 3 at 0:34

1

This delegate method is incorrect, and is probably never called. The correct method would be func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?), and it can't be a private method. The addService() method also isn't valid, but in any case, you would need to store the promise somewhere so you can later fulfill it.

– Rob Napier
Jan 3 at 1:15

OK, thanks. But I'm confused, the CBPeripheralManagerDelegate class doesn't have access to it's private functions?

– Eskel
Jan 3 at 19:16

1

The class has access to its own private methods, but CBPeripheralManager doesn't have access to its delegate's private methods. It's the manager that calls this method, not the delegate.

– Rob Napier
Jan 3 at 19:24

1

@Eskel Correct. That's the name of the signature I wrote: func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?). The name of that is peripheralManager(_:didAdd:error:).

– Rob Napier
Jan 4 at 21:46

What do you want it to do when the error happens, exactly? Whatever that is, just do it inside the if let block (or call a function from there to handle it and pass the error as a parameter).

– John Montgomery
Jan 3 at 0:34

This delegate method is incorrect, and is probably never called. The correct method would be func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?), and it can't be a private method. The addService() method also isn't valid, but in any case, you would need to store the promise somewhere so you can later fulfill it.

– Rob Napier
Jan 3 at 1:15

OK, thanks. But I'm confused, the CBPeripheralManagerDelegate class doesn't have access to it's private functions?

– Eskel
Jan 3 at 19:16

The class has access to its own private methods, but CBPeripheralManager doesn't have access to its delegate's private methods. It's the manager that calls this method, not the delegate.

– Rob Napier
Jan 3 at 19:24

@Eskel Correct. That's the name of the signature I wrote: func peripheralManager(_ peripheral: CBPeripheralManager, didAdd service: CBService, error: Error?). The name of that is peripheralManager(_:didAdd:error:).

– Rob Napier
Jan 4 at 21:46

|
show 1 more comment

1 Answer
1

active

oldest

votes

It's unclear what the type of promise is, but you'll need to store it somewhere, and then fulfill it later. For example, you might add a property:

var pendingServices: [CBUUID: Promise] = [:]

(I don't know what you're promise type really is here)

Then you'd store it in addService:

assert(pendingServices[serviceUUID] == nil)

pendingServices[serviceUUID] = promise

And later in (the correct; see my comment) delegate method, you'd deal with it:

if let promise = pendingServices.removeValue(forKey: service.uuid) {

    promise.fulfill() // Or whatever you do with it

}

answered Jan 3 at 1:19

Rob Napier

206k28305433

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

add a comment |

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1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

It's unclear what the type of promise is, but you'll need to store it somewhere, and then fulfill it later. For example, you might add a property:

var pendingServices: [CBUUID: Promise] = [:]

(I don't know what you're promise type really is here)

Then you'd store it in addService:

assert(pendingServices[serviceUUID] == nil)

pendingServices[serviceUUID] = promise

And later in (the correct; see my comment) delegate method, you'd deal with it:

if let promise = pendingServices.removeValue(forKey: service.uuid) {

    promise.fulfill() // Or whatever you do with it

}

answered Jan 3 at 1:19

Rob Napier

206k28305433

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

add a comment |

It's unclear what the type of promise is, but you'll need to store it somewhere, and then fulfill it later. For example, you might add a property:

var pendingServices: [CBUUID: Promise] = [:]

(I don't know what you're promise type really is here)

Then you'd store it in addService:

assert(pendingServices[serviceUUID] == nil)

pendingServices[serviceUUID] = promise

And later in (the correct; see my comment) delegate method, you'd deal with it:

if let promise = pendingServices.removeValue(forKey: service.uuid) {

    promise.fulfill() // Or whatever you do with it

}

answered Jan 3 at 1:19

Rob Napier

206k28305433

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

add a comment |

It's unclear what the type of promise is, but you'll need to store it somewhere, and then fulfill it later. For example, you might add a property:

var pendingServices: [CBUUID: Promise] = [:]

(I don't know what you're promise type really is here)

Then you'd store it in addService:

assert(pendingServices[serviceUUID] == nil)

pendingServices[serviceUUID] = promise

And later in (the correct; see my comment) delegate method, you'd deal with it:

if let promise = pendingServices.removeValue(forKey: service.uuid) {

    promise.fulfill() // Or whatever you do with it

}

answered Jan 3 at 1:19

Rob Napier

206k28305433

It's unclear what the type of promise is, but you'll need to store it somewhere, and then fulfill it later. For example, you might add a property:

var pendingServices: [CBUUID: Promise] = [:]

(I don't know what you're promise type really is here)

Then you'd store it in addService:

assert(pendingServices[serviceUUID] == nil)

pendingServices[serviceUUID] = promise

And later in (the correct; see my comment) delegate method, you'd deal with it:

if let promise = pendingServices.removeValue(forKey: service.uuid) {

    promise.fulfill() // Or whatever you do with it

}

answered Jan 3 at 1:19

Rob Napier

206k28305433

answered Jan 3 at 1:19

Rob Napier

206k28305433

answered Jan 3 at 1:19

Rob Napier

206k28305433

answered Jan 3 at 1:19

Rob Napier

206k28305433

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

add a comment |

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

Ah, I see. Seems a little complicated but I guess it's the only way. Too bad apple doesn't provide a way to use a my own custom function. Anyway, thank you!

– Eskel
Jan 3 at 19:12

add a comment |

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