Implement getPairedDevices api

Author: rohitsangwan01

android/src/main/kotlin/com/navideck/universal_ble/UniversalBle.g.kt

@@ -256,6 +256,7 @@ interface UniversalBlePlatformChannel {
   fun writeValue(deviceId: String, service: String, characteristic: String, value: ByteArray, bleOutputProperty: Long, callback: (Result<Unit>) -> Unit)
   fun isPaired(deviceId: String, callback: (Result<Boolean>) -> Unit)
   fun pair(deviceId: String)
+  fun getPairedDevices(): List<UniversalBleScanResult>
   fun unPair(deviceId: String)
   fun getSystemDevices(withServices: List<String>, callback: (Result<List<UniversalBleScanResult>>) -> Unit)
   fun getConnectionState(deviceId: String): Long
@@ -520,6 +521,21 @@ interface UniversalBlePlatformChannel {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.getPairedDevices$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { _, reply ->
+            val wrapped: List<Any?> = try {
+              listOf<Any?>(api.getPairedDevices())
+            } catch (exception: Throwable) {
+              wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.unPair$separatedMessageChannelSuffix", codec)
         if (api != null) {

android/src/main/kotlin/com/navideck/universal_ble/UniversalBlePlugin.kt

@@ -496,6 +496,20 @@ class UniversalBlePlugin : UniversalBlePlatformChannel, BluetoothGattCallback(),
         }
     }
 
+    override fun getPairedDevices(): List<UniversalBleScanResult> {
+        val bondedDevices: Set<BluetoothDevice> = bluetoothManager.adapter.bondedDevices;
+        return bondedDevices.map {
+            UniversalBleScanResult(
+                name = it.name,
+                deviceId = it.address,
+                isPaired = it.bondState == BOND_BONDED,
+                manufacturerDataHead = null,
+                manufacturerData = null,
+                rssi = null,
+            )
+        }
+    }
+
     override fun unPair(deviceId: String) {
         val remoteDevice: BluetoothDevice =
             bluetoothManager.adapter.getRemoteDevice(deviceId)

darwin/Classes/UniversalBle.g.swift

@@ -257,6 +257,7 @@ protocol UniversalBlePlatformChannel {
   func writeValue(deviceId: String, service: String, characteristic: String, value: FlutterStandardTypedData, bleOutputProperty: Int64, completion: @escaping (Result<Void, Error>) -> Void)
   func isPaired(deviceId: String, completion: @escaping (Result<Bool, Error>) -> Void)
   func pair(deviceId: String) throws
+  func getPairedDevices() throws -> [UniversalBleScanResult]
   func unPair(deviceId: String) throws
   func getSystemDevices(withServices: [String], completion: @escaping (Result<[UniversalBleScanResult], Error>) -> Void)
   func getConnectionState(deviceId: String) throws -> Int64
@@ -484,6 +485,19 @@ class UniversalBlePlatformChannelSetup {
     } else {
       pairChannel.setMessageHandler(nil)
     }
+    let getPairedDevicesChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.getPairedDevices\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
+    if let api = api {
+      getPairedDevicesChannel.setMessageHandler { _, reply in
+        do {
+          let result = try api.getPairedDevices()
+          reply(wrapResult(result))
+        } catch {
+          reply(wrapError(error))
+        }
+      }
+    } else {
+      getPairedDevicesChannel.setMessageHandler(nil)
+    }
     let unPairChannel = FlutterBasicMessageChannel(name: "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.unPair\(channelSuffix)", binaryMessenger: binaryMessenger, codec: codec)
     if let api = api {
       unPairChannel.setMessageHandler { message, reply in

darwin/Classes/UniversalBlePlugin.swift

@@ -287,7 +287,11 @@ private class BleCentralDarwin: NSObject, UniversalBlePlatformChannel, CBCentral
   func unPair(deviceId _: String) throws {
     throw FlutterError(code: "NotSupported", message: nil, details: nil)
   }
-
+    
+  func getPairedDevices() throws -> [UniversalBleScanResult] {
+    throw FlutterError(code: "NotSupported", message: nil, details: nil)
+  }
+    
   func getSystemDevices(withServices: [String], completion: @escaping (Result<[UniversalBleScanResult], Error>) -> Void) {
     var filterCBUUID = withServices.map { CBUUID(string: $0) }
     // We can't keep this filter empty, so adding a default filter

example/lib/data/mock_universal_ble.dart

@@ -111,4 +111,9 @@ class MockUniversalBle extends UniversalBlePlatform {
   Future<BleConnectionState> getConnectionState(String deviceId) {
     throw UnimplementedError();
   }
+
+  @override
+  Future<List<BleDevice>> getPairedDevices() async {
+    return <BleDevice>[];
+  }
 }

lib/src/universal_ble_linux/universal_ble_linux.dart

@@ -286,6 +286,14 @@ class UniversalBleLinux extends UniversalBlePlatform {
     }
   }
 
+  @override
+  Future<List<BleDevice>> getPairedDevices() async {
+    return _client.devices
+        .where((e) => e.paired)
+        .map((e) => e.toBleDevice())
+        .toList();
+  }
+
   @override
   Future<bool> isPaired(String deviceId) async {
     return _findDeviceById(deviceId).paired;