feat: 支持获取 maximumWrtieLength (#14)

bluetooth_low_energy_android/CHANGELOG.md

@@ -1,20 +1,24 @@
+## 2.2.0
+
+* Add `CentralController#getMaximumWriteLength` method.
+
 ## 2.0.3
 
-- `Android` Migrate to Android 13.
-- `Android` Fix the issuce that receive wrong values caused by unsafe memory, see https://developer.android.com/reference/android/bluetooth/BluetoothGattCallback#onCharacteristicChanged(android.bluetooth.BluetoothGatt,%20android.bluetooth.BluetoothGattCharacteristic)
+* `Android` Migrate to Android 13.
+* `Android` Fix the issuce that receive wrong values caused by unsafe memory, see https://developer.android.com/reference/android/bluetooth/BluetoothGattCallback#onCharacteristicChanged(android.bluetooth.BluetoothGatt,%20android.bluetooth.BluetoothGattCharacteristic)
 
 ## 2.0.2
 
-- Combine iOS and macOS projects.
-- Optimize project structure.
+* Combine iOS and macOS projects.
+* Optimize project structure.
 
 ## 2.0.1
 
-- Fix the issue that GATTs is cleared after peripheral disconnected on iOS and macOS.
-- Fix the issue that create UUID form peripheral's address failed on Linux.
-- Fix the issue that instance match failed on Linux.
+* Fix the issue that GATTs is cleared after peripheral disconnected on iOS and macOS.
+* Fix the issue that create UUID form peripheral's address failed on Linux.
+* Fix the issue that instance match failed on Linux.
 
 ## 2.0.0
 
-- Rewrite the whole project with federated plugins.
-- Support macOS and Linux.
+* Rewrite the whole project with federated plugins.
+* Support macOS and Linux.

bluetooth_low_energy_android/android/src/main/kotlin/dev/yanshouwang/bluetooth_low_energy_android/MyApi.g.kt

@@ -278,6 +278,7 @@ interface MyCentralControllerHostApi {
   fun stopDiscovery()
   fun connect(myPeripheralKey: Long, callback: (Result<Unit>) -> Unit)
   fun disconnect(myPeripheralKey: Long, callback: (Result<Unit>) -> Unit)
+  fun getMaximumWriteLength(myPeripheralKey: Long, callback: (Result<Long>) -> Unit)
   fun discoverGATT(myPeripheralKey: Long, callback: (Result<Unit>) -> Unit)
   fun getServices(myPeripheralKey: Long): List<MyGattServiceArgs>
   fun getCharacteristics(myServiceKey: Long): List<MyGattCharacteristicArgs>
@@ -403,6 +404,26 @@ interface MyCentralControllerHostApi {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.bluetooth_low_energy_android.MyCentralControllerHostApi.getMaximumWriteLength", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val myPeripheralKeyArg = args[0].let { if (it is Int) it.toLong() else it as Long }
+            api.getMaximumWriteLength(myPeripheralKeyArg) { result: Result<Long> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(wrapError(error))
+              } else {
+                val data = result.getOrNull()
+                reply.reply(wrapResult(data))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.bluetooth_low_energy_android.MyCentralControllerHostApi.discoverGATT", codec)
         if (api != null) {

bluetooth_low_energy_android/android/src/main/kotlin/dev/yanshouwang/bluetooth_low_energy_android/MyBluetoothGattCallback.kt

@@ -15,6 +15,13 @@ class MyBluetoothGattCallback(private val myCentralController: MyCentralControll
         }
     }
 
+    override fun onMtuChanged(gatt: BluetoothGatt, mtu: Int, status: Int) {
+        super.onMtuChanged(gatt, mtu, status)
+        executor.execute {
+            myCentralController.onMtuChanged(gatt, mtu, status)
+        }
+    }
+
     override fun onServicesDiscovered(gatt: BluetoothGatt, status: Int) {
         super.onServicesDiscovered(gatt, status)
         executor.execute {

bluetooth_low_energy_android/android/src/main/kotlin/dev/yanshouwang/bluetooth_low_energy_android/MyCentralController.kt

@@ -59,6 +59,7 @@ class MyCentralController(private val context: Context, binaryMessenger: BinaryM
     private var startDiscoveryCallback: ((Result<Unit>) -> Unit)? = null
     private val connectCallbacks = mutableMapOf<Int, (Result<Unit>) -> Unit>()
     private val disconnectCallbacks = mutableMapOf<Int, (Result<Unit>) -> Unit>()
+    private val getMaximumWriteLengthCallbacks = mutableMapOf<Int, (Result<Long>) -> Unit>()
     private val discoverGattCallbacks = mutableMapOf<Int, (Result<Unit>) -> Unit>()
     private val readCharacteristicCallbacks = mutableMapOf<Int, (Result<ByteArray>) -> Unit>()
     private val writeCharacteristicCallbacks = mutableMapOf<Int, (Result<Unit>) -> Unit>()
@@ -179,6 +180,24 @@ class MyCentralController(private val context: Context, binaryMessenger: BinaryM
         }
     }
 
+    override fun getMaximumWriteLength(myPeripheralKey: Long, callback: (Result<Long>) -> Unit) {
+        try {
+            val deviceKey = myPeripheralKey.toInt()
+            val unfinishedCallback = getMaximumWriteLengthCallbacks[deviceKey]
+            if (unfinishedCallback != null) {
+                throw IllegalStateException()
+            }
+            val gatt = cachedGATTs[deviceKey] as BluetoothGatt
+            val requesting = gatt.requestMtu(512)
+            if (!requesting) {
+                throw IllegalStateException()
+            }
+            getMaximumWriteLengthCallbacks[deviceKey] = callback
+        } catch (e: Throwable) {
+            callback(Result.failure(e))
+        }
+    }
+
     override fun discoverGATT(myPeripheralKey: Long, callback: (Result<Unit>) -> Unit) {
         try {
             val deviceKey = myPeripheralKey.toInt()
@@ -493,6 +512,19 @@ class MyCentralController(private val context: Context, binaryMessenger: BinaryM
         }
     }
 
+    fun onMtuChanged(gatt: BluetoothGatt, mtu: Int, status: Int) {
+        val device = gatt.device
+        val deviceKey = device.hashCode()
+        val callback = getMaximumWriteLengthCallbacks.remove(deviceKey) ?: return
+        if (status == BluetoothGatt.GATT_SUCCESS) {
+            val maximumWriteLength = (mtu - 3).toLong()
+            callback(Result.success(maximumWriteLength))
+        } else {
+            val error = IllegalStateException("Get maximum write length failed with status: $status")
+            callback(Result.failure(error))
+        }
+    }
+
     fun onServicesDiscovered(gatt: BluetoothGatt, status: Int) {
         val device = gatt.device
         val deviceKey = device.hashCode()
@@ -609,7 +641,8 @@ private val ScanResult.myAdvertisementArgs: MyAdvertisementArgs
         } else {
             val name = record.deviceName
             val manufacturerSpecificData = record.manufacturerSpecificData.toMyArgs()
-            val serviceUUIDs = record.serviceUuids?.map { uuid -> uuid.toString() } ?: emptyList()
+            val serviceUUIDs = record.serviceUuids?.map { uuid -> uuid.toString() }
+                    ?: emptyList()
             val pairs = record.serviceData.entries.map { (uuid, value) ->
                 val key = uuid.toString()
                 return@map Pair(key, value)

bluetooth_low_energy_android/lib/src/my_api.g.dart

@@ -380,6 +380,33 @@ class MyCentralControllerHostApi {
     }
   }
 
+  Future<int> getMaximumWriteLength(int arg_myPeripheralKey) async {
+    final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
+        'dev.flutter.pigeon.bluetooth_low_energy_android.MyCentralControllerHostApi.getMaximumWriteLength', codec,
+        binaryMessenger: _binaryMessenger);
+    final List<Object?>? replyList =
+        await channel.send(<Object?>[arg_myPeripheralKey]) as List<Object?>?;
+    if (replyList == null) {
+      throw PlatformException(
+        code: 'channel-error',
+        message: 'Unable to establish connection on channel.',
+      );
+    } else if (replyList.length > 1) {
+      throw PlatformException(
+        code: replyList[0]! as String,
+        message: replyList[1] as String?,
+        details: replyList[2],
+      );
+    } else if (replyList[0] == null) {
+      throw PlatformException(
+        code: 'null-error',
+        message: 'Host platform returned null value for non-null return value.',
+      );
+    } else {
+      return (replyList[0] as int?)!;
+    }
+  }
+
   Future<void> discoverGATT(int arg_myPeripheralKey) async {
     final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
         'dev.flutter.pigeon.bluetooth_low_energy_android.MyCentralControllerHostApi.discoverGATT', codec,

bluetooth_low_energy_android/lib/src/my_central_controller.dart

@@ -114,6 +114,19 @@ class MyCentralController extends CentralController
     await _myApi.disconnect(myPeripheral.hashCode);
   }
 
+  @override
+  Future<int> getMaximumWriteLength(
+    Peripheral peripheral, {
+    required GattCharacteristicWriteType type,
+  }) async {
+    await _throwWithoutState(CentralState.poweredOn);
+    final myPeripheral = peripheral as MyPeripheral;
+    final maximumWriteLength = await _myApi.getMaximumWriteLength(
+      myPeripheral.hashCode,
+    );
+    return maximumWriteLength;
+  }
+
   @override
   Future<void> discoverGATT(Peripheral peripheral) async {
     await _throwWithoutState(CentralState.poweredOn);
@@ -205,14 +218,14 @@ class MyCentralController extends CentralController
     final myCharacteristic = characteristic as MyGattCharacteristic;
     final myService = myCharacteristic.myService;
     final myPeripheral = myService.myPeripheral;
-    final typeArgs = type.toMyArgs();
-    final typeNumber = typeArgs.index;
+    final myTypeArgs = type.toMyArgs();
+    final myTypeNumber = myTypeArgs.index;
     await _myApi.writeCharacteristic(
       myPeripheral.hashCode,
       myService.hashCode,
       myCharacteristic.hashCode,
       value,
-      typeNumber,
+      myTypeNumber,
     );
   }
 

bluetooth_low_energy_android/my_api.dart

@@ -24,6 +24,8 @@ abstract class MyCentralControllerHostApi {
   @async
   void disconnect(int myPeripheralKey);
   @async
+  int getMaximumWriteLength(int myPeripheralKey);
+  @async
   void discoverGATT(int myPeripheralKey);
   List<MyGattServiceArgs> getServices(int myPeripheralKey);
   List<MyGattCharacteristicArgs> getCharacteristics(int myServiceKey);

bluetooth_low_energy_android/pubspec.yaml

@@ -1,6 +1,6 @@
 name: bluetooth_low_energy_android
 description: Android implementation of the bluetooth_low_energy plugin.
-version: 2.0.3
+version: 2.2.0
 homepage: https://github.com/yanshouwang/bluetooth_low_energy
 
 environment:
@@ -10,7 +10,7 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
-  bluetooth_low_energy_platform_interface: ^2.0.3
+  bluetooth_low_energy_platform_interface: ^2.2.0
 
 dev_dependencies:
   flutter_test: