1 files changed, 9 insertions, 1 deletions
diff --git a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
index e6d59e4..444705c 100644
--- a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
+++ b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
@@ -147,14 +147,22 @@ public final class BluetoothMidiDevice {
             // switch to receiving notifications after initial characteristic read
             mBluetoothGatt.setCharacteristicNotification(characteristic, true);
 
+            // Use writeType that requests acknowledgement.
+            // This improves compatibility with various BLE-MIDI devices.
+            int originalWriteType = characteristic.getWriteType();
+            characteristic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT);
+
             BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
                     CLIENT_CHARACTERISTIC_CONFIG);
             if (descriptor != null) {
                 descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
-                mBluetoothGatt.writeDescriptor(descriptor);
+                boolean result = mBluetoothGatt.writeDescriptor(descriptor);
+                Log.d(TAG, "writeDescriptor returned " + result);
             } else {
                 Log.e(TAG, "No CLIENT_CHARACTERISTIC_CONFIG for device " + mBluetoothDevice);
             }
+
+            characteristic.setWriteType(originalWriteType);
         }
 
         @Override