- Finally added support for reconnecting to a device that wasn't explicitly disconnected by the user

- Set application characteristics to include permission to run in the background to maintain current BLE connections, and reconnect to the device if it disconnects unexpectedly
- Added functionality to the autoconnect option: rather than grabbing the first device named InfiniTime, the user can manually connect to a device, and then press a button in the settings to save the UUID of the connected device. On app open, if autoconnect is enabled, scan for devices until it sees that UUID, then connect immediately.

Author: xan-m

Infini-iOS/BLE/BLEDelegates.swift

@@ -27,29 +27,13 @@ extension BLEManager: CBPeripheralDelegate {
 			if characteristic.properties.contains(.read) {
 				peripheral.readValue(for: characteristic)
 			}
-			// MARK: - Subscribe to services
-			// subscribe to HRM, battery, and music control characteristics
-			if characteristic.properties.contains(.notify) {
-				/*switch characteristic.uuid {
-				case musicControlCBUUID:
-					//peripheral.setNotifyValue(true, for: characteristic)
-				case hrmCBUUID:
-					//peripheral.setNotifyValue(true, for: characteristic)
-				case batCBUUID:
-					//peripheral.setNotifyValue(true, for: characteristic)
-					break
-				default:
-					break
-				}
-				peripheral.setNotifyValue(true, for: characteristic)*/
-				print(characteristic.uuid, " can notify")
-			}
 
-			if characteristic.properties.contains(.write) {
-				if characteristic.uuid == notifyCBUUID {
-					// I'm sure there's a less clunky way to grab the full characteristic for the sendNotification() function, but this works fine for now
-					notifyCharacteristic = characteristic
+			if characteristic.uuid == notifyCBUUID {
+				// I'm sure there's a less clunky way to grab the full characteristic for the sendNotification() function, but this works fine for now
+				notifyCharacteristic = characteristic
+				if firstConnect {
 					sendNotification(notification: "iOS Connected!")
+					firstConnect = false
 				}
 			}
 		}

Infini-iOS/BLE/BLEManager.swift

@@ -20,6 +20,14 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 		var artist: CBCharacteristic!
 	}
 
+	struct Peripheral: Identifiable {
+		let id: Int
+		let name: String
+		let rssi: Int
+		let peripheralHash: Int
+		let deviceUUID: CBUUID
+	}
+	
 	@Published var musicChars = musicCharacteristics()
 
 	let settings = UserDefaults.standard
@@ -29,14 +37,18 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 	@Published var isScanning = false									// another UI flag. Probably not necessary for anything but debugging. I dunno maybe a little swirly animation or something could be triggered by this
 	@Published var isConnectedToPinetime = false						// another flag published to update UI stuff. Can probably be implemented better in the future
 	@Published var heartBPM: String = "Disconnected"					// published var to communicate the HRM data to the UI.
-	@Published var batteryLevel: String = "20"//"Disconnected"				// Same as heartBPM but for battery data
+	@Published var batteryLevel: String = "Disconnected"				// Same as heartBPM but for battery data
 	@Published var firmwareVersion: String = "Disconnected"
 
 	// Selecting and connecting variables
 	@Published var peripherals = [Peripheral]() 						// used to print human-readable device names to UI in selection process
 	@Published var deviceToConnect: Int!								// When the user selects a device from the UI, that peripheral's ID goes in this var, which is passed to the peripheralDictionary
 	@Published var peripheralDictionary: [Int: CBPeripheral] = [:] 		// this is the dictionary that relates human-readable peripheral names to the CBPeripheral class that CoreBluetooth actually interacts with
 	@Published var infiniTime: CBPeripheral!							// variable to save the CBPeripheral that you're connecting to
+	@Published var autoconnectPeripheral: CBPeripheral!
+	@Published var setAutoconnectUUID: String = ""							// placeholder for now while I figure out how to save the whole device in UserDefaults to save "favorite" devices
+	
+	var firstConnect: Bool = true										// makes iOS connected message only show up on first connect, not if device drops connection and reconnects
 
 	// declare some CBUUIDs for easier reference
 	let hrmCBUUID = CBUUID(string: "2A37")
@@ -48,12 +60,7 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 	let musicTrackCBUUID = CBUUID(string: "00000004-78FC-48FE-8E23-433B3A1942D0")
 	let musicArtistCBUUID = CBUUID(string: "00000003-78FC-48FE-8E23-433B3A1942D0")
 
-	struct Peripheral: Identifiable {
-		let id: Int
-		let name: String
-		let rssi: Int
-		let peripheralHash: Int
-	}
+
 
 	override init() {
 		super.init()
@@ -78,6 +85,7 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 	func disconnect(){
 		if infiniTime != nil {
 			myCentral.cancelPeripheralConnection(infiniTime)
+			firstConnect = true
 		}
 	}
 
@@ -92,6 +100,19 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 			infiniTime.delegate = self
 			self.myCentral.connect(peripheral, options: nil)
 
+			setAutoconnectUUID = peripheral.identifier.uuidString
+			isConnectedToPinetime = true
+		}
+	}
+	func autoconnect() {
+		if autoconnectPeripheral != nil {
+			self.myCentral.stopScan()
+			isScanning = false
+			
+			self.infiniTime = autoconnectPeripheral
+			infiniTime.delegate = self
+			self.myCentral.connect(autoconnectPeripheral, options: nil)
+			
 			isConnectedToPinetime = true
 		}
 	}
@@ -109,35 +130,50 @@ class BLEManager: NSObject, ObservableObject, CBCentralManagerDelegate {
 			- the hash I'm using is only unique between PineTimes because the peripheral struct includes an incrementing ID number that's part of the hash.
 				- this works for getting more than one PT in the menu, but is obviously a drag because it's not at all guaranteed to be persistent
 			- there's some stuff happening here that doesn't need to happen - ex. there's an array and a dictionary doing basically the same thing?
+			- I mistakenly was under the impression that the UUID was generated by InfiniTime and was probably the same across all instances of InfiniTime, but it seems like that's incorrect!
 		*/
 
 		if let name = advertisementData[CBAdvertisementDataLocalNameKey] as? String {
 			peripheralName = name
-			let newPeripheral = Peripheral(id: peripheralDictionary.count, name: peripheralName, rssi: RSSI.intValue, peripheralHash: peripheral.hash)
+			let devUUIDString: String = peripheral.identifier.uuidString
+			//setAutoconnectUUID = devUUIDString
+			let devUUID: CBUUID = CBUUID(string: devUUIDString)
+			let newPeripheral = Peripheral(id: peripheralDictionary.count, name: peripheralName, rssi: RSSI.intValue, peripheralHash: peripheral.hash, deviceUUID: devUUID)
+			
+			print(peripheralName + ": " + String(peripheral.identifier.uuidString))
 
-			let autoconnect = UserDefaults.standard.object(forKey: "autoconnect") as? Bool ?? true
+			// handle autoconnect defaults
+			let settings = UserDefaults.standard
+			let autoconnect = settings.object(forKey: "autoconnect") as? Bool ?? true
+			let autoconnectUUID = settings.object(forKey: "autoconnectUUID") as! String
 
-			if autoconnect {
+			if autoconnect && devUUIDString == autoconnectUUID {
 				connect(peripheral: peripheral)
 			}
 			else {
 				// compare peripheral hashes to make sure we're only adding each device once -- super helpful if you have a very noisy BLE advertiser nearby!
-				if !peripherals.contains(where: {$0.peripheralHash == newPeripheral.peripheralHash}) {
+				if !peripherals.contains(where: {$0.deviceUUID == newPeripheral.deviceUUID}) {
 					peripherals.append(newPeripheral)
 					peripheralDictionary[newPeripheral.peripheralHash] = peripheral
 
-					print(newPeripheral, "added to list")
+					//print(newPeripheral, "added to list")
 				}
 			}
 		}
 	}
 
+	func centralManager(_ central: CBCentralManager, didFailToConnect peripheral: CBPeripheral, error: Error?) {
+		print(error ?? "no error")
+	}
+	
 	func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {
 		self.infiniTime.discoverServices(nil)
 	}
 
 	func centralManager(_ central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: Error?) {
-		isConnectedToPinetime = false
+		if error != nil {
+			connect(peripheral: peripheral)
+		}
 	}
 
 	func centralManagerDidUpdateState(_ central: CBCentralManager) {

Infini-iOS/Info.plist

@@ -24,13 +24,19 @@
 	<string>This app needs permission to allow your PineTime to control your music.</string>
 	<key>NSBluetoothAlwaysUsageDescription</key>
 	<string>This app uses bluetooth to communicate with your PineTime.</string>
+	<key>NSBluetoothPeripheralUsageDescription</key>
+	<string>This app uses bluetooth to communicate with your PineTime.</string>
 	<key>UIApplicationSceneManifest</key>
 	<dict>
 		<key>UIApplicationSupportsMultipleScenes</key>
 		<true/>
 	</dict>
 	<key>UIApplicationSupportsIndirectInputEvents</key>
 	<true/>
+	<key>UIBackgroundModes</key>
+	<array>
+		<string>bluetooth-central</string>
+	</array>
 	<key>UILaunchScreen</key>
 	<dict/>
 	<key>UIRequiredDeviceCapabilities</key>

Infini-iOS/Settings/SettingsView.swift

@@ -17,6 +17,7 @@ struct Settings_Page: View {
 	@AppStorage("watchNotifications") var watchNotifications: Bool = true
 	@AppStorage("autoconnect") var autoconnect: Bool = false
 	@AppStorage("batteryNotification") var batteryNotification: Bool = false
+	@AppStorage("autoconnectUUID") var autoconnectUUID: String = "empty"
 
 
 	var body: some View {
@@ -28,8 +29,15 @@ struct Settings_Page: View {
 				Section(header: Text("Connection")) {
 					Toggle("Autoconnect to Nearest PineTime", isOn: $autoconnect)
 					if autoconnect {
-					Text("Warning! Autoconnect is insecure! Only use in safe environments.").foregroundColor(Color.red)
+					Text("Autoconnect is currently experimental! Connection is made based on device UUID, which I am only sort of sure is static.").foregroundColor(Color.red)
 					}
+					Button {
+						autoconnectUUID = bleManager.setAutoconnectUUID
+						print(autoconnectUUID)
+					} label: {
+						Text("Select Current Device for Autoconnect")
+					}
+
 				}
 				Section(header: Text("Notifications")) {
 					Toggle("Enable Watch Notifications", isOn: $watchNotifications)

Infini-iOS/View Components/BLEConnectView.swift

@@ -12,6 +12,8 @@ struct Connect: View {
 
 	@EnvironmentObject var bleManager: BLEManager
 	@State var scanOrStopScan: Bool = true
+	@AppStorage("autoconnect") var autoconnect: Bool = false
+	@AppStorage("autoconnectUUID") var autoconnectUUID: String = ""
 
 	var body: some View {
 
@@ -36,12 +38,16 @@ struct Connect: View {
 
 			Spacer()
 
-			let autoconnect = UserDefaults.standard.object(forKey: "autoconnect") as? Bool ?? true
+			//let autoconnect = UserDefaults.standard.object(forKey: "autoconnect") as? Bool ?? true
 			if autoconnect {
-				Button(action: {
-					self.bleManager.startScanning()
-				}) {
-					Text("Autoconnect")
+				//Button(action: {
+				//	self.bleManager.startScanning()
+				//}) {
+				if bleManager.isSwitchedOn {
+					Text("Scanning")
+						.onAppear {
+							self.bleManager.startScanning()
+						}
 						.padding()
 						.padding(.vertical, 7)
 						.frame(maxWidth: .infinity, alignment: .center)
@@ -50,7 +56,6 @@ struct Connect: View {
 						.cornerRadius(10)
 						.padding(.horizontal, 20)
 				}
-
 			} else {
 				if scanOrStopScan {
 					Button(action: {

Infini-iOS/View Components/BLEStatusView.swift

@@ -16,9 +16,9 @@ struct DeviceView: View {
 		VStack (spacing: 10){
 			Text("InfiniTime Status")
 				.font(.largeTitle)
-				.frame(maxWidth: .infinity, alignment: .center)
-				.padding(.bottom, 30)
-
+				.padding()
+				.frame(maxWidth: .infinity, alignment: .leading)
+			
 			HStack (spacing: 10){
 				Text("Heart Rate: ")
 					.font(.title)

Infini-iOS/View Components/DFUView.swift

@@ -24,8 +24,8 @@ struct DFU_Page: View {
 		VStack (spacing: 10){
 			Text("Firmware Update")
 				.font(.largeTitle)
-				.frame(maxWidth: .infinity, alignment: .center)
-				.padding(.bottom, 30)
+				.padding()
+				.frame(maxWidth: .infinity, alignment: .leading)
 
 			HStack (spacing: 10){
 				Text("Current Firmware: ")