// Some peripherals re-use UUIDs for multiple characteristics so we need to check the properties
// and UUID of all characteristics instead of using service.getCharacteristic(characteristicUUID)
private BluetoothGattCharacteristic findWritableCharacteristic(
BluetoothGattService service, UUID characteristicUUID, int writeType) {
try {
BluetoothGattCharacteristic characteristic = null;
// get write property
int writeProperty = BluetoothGattCharacteristic.PROPERTY_WRITE;
if (writeType == BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE) {
writeProperty = BluetoothGattCharacteristic.PROPERTY_WRITE_NO_RESPONSE;
}
List<BluetoothGattCharacteristic> characteristics = service.getCharacteristics();
for (BluetoothGattCharacteristic c : characteristics) {
if ((c.getProperties() & writeProperty) != 0 && characteristicUUID.equals(c.getUuid())) {
characteristic = c;
break;
}
}
// As a last resort, try and find ANY characteristic with this UUID, even if it doesn't have
// the correct properties
if (characteristic == null) {
characteristic = service.getCharacteristic(characteristicUUID);
}
return characteristic;
} catch (Exception e) {
Log.e(LOG_TAG, "Errore su findWritableCharacteristic", e);
return null;
}
}
// Some devices reuse UUIDs across characteristics, so we can't use
// service.getCharacteristic(characteristicUUID)
// instead check the UUID and properties for each characteristic in the service until we find the
// best match
// This function prefers Notify over Indicate
private BluetoothGattCharacteristic findNotifyCharacteristic(
BluetoothGattService service, UUID characteristicUUID) {
BluetoothGattCharacteristic characteristic = null;
try {
// Check for Notify first
List<BluetoothGattCharacteristic> characteristics = service.getCharacteristics();
for (BluetoothGattCharacteristic c : characteristics) {
if ((c.getProperties() & BluetoothGattCharacteristic.PROPERTY_NOTIFY) != 0
&& characteristicUUID.equals(c.getUuid())) {
characteristic = c;
break;
}
}
if (characteristic != null) return characteristic;
// If there wasn't Notify Characteristic, check for Indicate
for (BluetoothGattCharacteristic c : characteristics) {
if ((c.getProperties() & BluetoothGattCharacteristic.PROPERTY_INDICATE) != 0
&& characteristicUUID.equals(c.getUuid())) {
characteristic = c;
break;
}
}
// As a last resort, try and find ANY characteristic with this UUID, even if it doesn't have
// the correct properties
if (characteristic == null) {
characteristic = service.getCharacteristic(characteristicUUID);
}
return characteristic;
} catch (Exception e) {
Log.e(LOG_TAG, "Errore su caratteristica " + characteristicUUID, e);
return null;
}
}
// Some peripherals re-use UUIDs for multiple characteristics so we need to check the properties
// and UUID of all characteristics instead of using service.getCharacteristic(characteristicUUID)
private BluetoothGattCharacteristic findReadableCharacteristic(
BluetoothGattService service, UUID characteristicUUID) {
BluetoothGattCharacteristic characteristic = null;
int read = BluetoothGattCharacteristic.PROPERTY_READ;
List<BluetoothGattCharacteristic> characteristics = service.getCharacteristics();
for (BluetoothGattCharacteristic c : characteristics) {
if ((c.getProperties() & read) != 0 && characteristicUUID.equals(c.getUuid())) {
characteristic = c;
break;
}
}
// As a last resort, try and find ANY characteristic with this UUID, even if it doesn't have the
// correct properties
if (characteristic == null) {
characteristic = service.getCharacteristic(characteristicUUID);
}
return characteristic;
}
// This seems way too complicated
public void registerNotify(
UUID serviceUUID, UUID characteristicUUID, Callback success, Callback fail) {
Log.d(LOG_TAG, "registerNotify");
if (gatt == null) {
fail.invoke("BluetoothGatt is null");
return;
}
BluetoothGattService service = gatt.getService(serviceUUID);
BluetoothGattCharacteristic characteristic =
findNotifyCharacteristic(service, characteristicUUID);
// String key = generateHashKey(serviceUUID, characteristic);
if (characteristic != null) {
Log.d(LOG_TAG, "characteristic ok");
if (gatt.setCharacteristicNotification(characteristic, true)) {
BluetoothGattDescriptor descriptor =
characteristic.getDescriptor(UUID.fromString(CHARACTERISTIC_NOTIFICATION_CONFIG));
if (descriptor != null) {
Log.d(LOG_TAG, "trovato descriptor");
// prefer notify over indicate
if ((characteristic.getProperties() & BluetoothGattCharacteristic.PROPERTY_NOTIFY) != 0) {
Log.d(LOG_TAG, "Characteristic " + characteristicUUID + " set NOTIFY");
descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
} else if ((characteristic.getProperties()
& BluetoothGattCharacteristic.PROPERTY_INDICATE)
!= 0) {
Log.d(LOG_TAG, "Characteristic " + characteristicUUID + " set INDICATE");
descriptor.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE);
} else {
Log.d(
LOG_TAG,
"Characteristic "
+ characteristicUUID
+ " does not have NOTIFY or INDICATE property set");
}
if (gatt.writeDescriptor(descriptor)) {
// Tutto ok
Log.d(LOG_TAG, "registerNotify completato");
success.invoke();
} else {
fail.invoke(
"Failed to set client characteristic notification for " + characteristicUUID);
}
} else {
fail.invoke("Set notification failed for " + characteristicUUID);
}
} else {
fail.invoke("Failed to register notification for " + characteristicUUID);
}
} else {
fail.invoke("Characteristic " + characteristicUUID + " not found");
}
}
