Add descriptor read and write API

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## Unreleased
 * Windows: Harden BLE connection lifetime, asynchronous callbacks, and notification subscription handling
 * Android: instantly close the GATT client on disconnect
+* Add Descriptor Read and Write apis
 
 ## 2.1.1
 * Android: Fix BluetoothDevice null-safety compile error under Kotlin 2.x

README.md

@@ -347,6 +347,16 @@ await characteristic.write([0x01, 0x02, 0x03]);
 await characteristic.write([0x01, 0x02, 0x03], withResponse: false);
 ```
 
+To read or write a descriptor of this characteristic
+
+```dart
+Uint8List value = await characteristic.descriptor('2901').read();
+```
+
+```dart
+await characteristic.descriptor('2901').write([0x01, 0x02, 0x03]);
+```
+
 ## Subscriptions
 
 Get `BleCharacteristic` using `bleDevice.getCharacteristic`

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

@@ -1714,8 +1714,10 @@ interface UniversalBlePlatformChannel {
   fun setNotifiable(deviceId: String, service: String, characteristic: String, bleInputProperty: BleInputProperty, callback: (Result<Unit>) -> Unit)
   fun discoverServices(deviceId: String, withDescriptors: Boolean, callback: (Result<List<UniversalBleService>>) -> Unit)
   fun readValue(deviceId: String, service: String, characteristic: String, callback: (Result<ByteArray>) -> Unit)
+  fun readDescriptorValue(deviceId: String, service: String, characteristic: String, descriptor: String, callback: (Result<ByteArray>) -> Unit)
   fun requestMtu(deviceId: String, expectedMtu: Long, callback: (Result<Long>) -> Unit)
   fun writeValue(deviceId: String, service: String, characteristic: String, value: ByteArray, bleOutputProperty: BleOutputProperty, callback: (Result<Unit>) -> Unit)
+  fun writeDescriptorValue(deviceId: String, service: String, characteristic: String, descriptor: String, value: ByteArray, callback: (Result<Unit>) -> Unit)
   fun isPaired(deviceId: String, callback: (Result<Boolean>) -> Unit)
   fun pair(deviceId: String, callback: (Result<Boolean>) -> Unit)
   fun unPair(deviceId: String)
@@ -1977,6 +1979,29 @@ interface UniversalBlePlatformChannel {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.readDescriptorValue$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val deviceIdArg = args[0] as String
+            val serviceArg = args[1] as String
+            val characteristicArg = args[2] as String
+            val descriptorArg = args[3] as String
+            api.readDescriptorValue(deviceIdArg, serviceArg, characteristicArg, descriptorArg) { result: Result<ByteArray> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(UniversalBlePigeonUtils.wrapError(error))
+              } else {
+                val data = result.getOrNull()
+                reply.reply(UniversalBlePigeonUtils.wrapResult(data))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.requestMtu$separatedMessageChannelSuffix", codec)
         if (api != null) {
@@ -2021,6 +2046,29 @@ interface UniversalBlePlatformChannel {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.writeDescriptorValue$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val deviceIdArg = args[0] as String
+            val serviceArg = args[1] as String
+            val characteristicArg = args[2] as String
+            val descriptorArg = args[3] as String
+            val valueArg = args[4] as ByteArray
+            api.writeDescriptorValue(deviceIdArg, serviceArg, characteristicArg, descriptorArg, valueArg) { result: Result<Unit> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(UniversalBlePigeonUtils.wrapError(error))
+              } else {
+                reply.reply(UniversalBlePigeonUtils.wrapResult(null))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.universal_ble.UniversalBlePlatformChannel.isPaired$separatedMessageChannelSuffix", codec)
         if (api != null) {

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

@@ -462,4 +462,20 @@ class SubscriptionResultFuture(
 class RssiResultFuture(
     val deviceId: String,
     val result: (Result<Long>) -> Unit,
+)
+
+class ReadDescriptorResultFuture(
+    val deviceId: String,
+    val descriptorId: String,
+    val characteristicId: String,
+    val serviceId: String,
+    val result: (Result<ByteArray>) -> Unit,
+)
+
+class WriteDescriptorResultFuture(
+    val deviceId: String,
+    val descriptorId: String,
+    val characteristicId: String,
+    val serviceId: String,
+    val result: (Result<Unit>) -> Unit,
 )