react-native-ble-manager
This is a porting of https://github.com/don/cordova-plugin-ble-central project to React Native.
Requirements
RN 0.60+
RN 0.40-0.59 supported until 6.7.X
RN 0.30-0.39 supported until 2.4.3
Supported Platforms
Install
npm i --save react-native-ble-manager
The library support the react native autolink feature.
Android - Update Manifest
// file: android/app/src/main/AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="YOUR_PACKAGE_NAME">
<uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" android:maxSdkVersion="28"/>
<uses-permission-sdk-23 android:name="android.permission.ACCESS_FINE_LOCATION" tools:targetApi="Q"/>
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT"
android:usesPermissionFlags="neverForLocation"
tools:targetApi="s" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
...
If you need communication while the app is not in the foreground you need the "ACCESS_BACKGROUND_LOCATION" permission.
iOS - Update Info.plist
In iOS >= 13 you need to add the NSBluetoothAlwaysUsageDescription
string key.
Note
- Remember to use the
start
method before anything. - If you have problem with old devices try avoid to connect/read/write to a peripheral during scan.
- Android API >= 23 require the ACCESS_COARSE_LOCATION permission to scan for peripherals. React Native >= 0.33 natively support PermissionsAndroid like in the example.
- Android API >= 29 require the ACCESS_FINE_LOCATION permission to scan for peripherals.
React-Native 0.63.X started targeting Android API 29.
- Before write, read or start notification you need to call
retrieveServices
method - Because location and bluetooth permissions are runtime permissions, you must request these permissions at runtime along with declaring them in your manifest.
Example
The easiest way to test is simple make your AppRegistry point to our example component, like this:
import React, { Component } from "react";
import { AppRegistry } from "react-native";
import App from "react-native-ble-manager/example/App";
AppRegistry.registerComponent("MyAwesomeApp", () => App);
Or, you can still look into the whole example folder for a standalone project.
Methods
start(options)
Init the module.
Returns a Promise
object.
Don't call this multiple times.
Arguments
The parameter is optional the configuration keys are:
showAlert
- Boolean
- [iOS only] Show or hide the alert if the bluetooth is turned off during initializationrestoreIdentifierKey
- String
- [iOS only] Unique key to use for CoreBluetooth state restorationqueueIdentifierKey
- String
- [iOS only] Unique key to use for a queue identifier on which CoreBluetooth events will be dispatchedforceLegacy
- Boolean
- [Android only] Force to use the LegacyScanManager
Examples
BleManager.start({ showAlert: false }).then(() => {
console.log("Module initialized");
});
scan(serviceUUIDs, seconds, allowDuplicates, scanningOptions)
Scan for availables peripherals.
Returns a Promise
object.
Arguments
serviceUUIDs
- Array of String
- the UUIDs of the services to looking for. On Android the filter works only for 5.0 or newer.seconds
- Integer
- the amount of seconds to scan.allowDuplicates
- Boolean
- [iOS only] allow duplicates in device scanningscanningOptions
- JSON
- [Android only] after Android 5.0, user can control specific ble scan behaviors:
numberOfMatches
- Number
- [Android only] corresponding to setNumOfMatches
matchMode
- Number
- [Android only] corresponding to setMatchMode
scanMode
- Number
- [Android only] corresponding to setScanMode
reportDelay
- Number
- [Android only] corresponding to setReportDelay
phy
- Number
- [Android only] corresponding to setPhy
legacy
- Boolean
- [Android only] corresponding to setLegacy
Examples
BleManager.scan([], 5, true).then(() => {
console.log("Scan started");
});
stopScan()
Stop the scanning.
Returns a Promise
object.
Examples
BleManager.stopScan().then(() => {
console.log("Scan stopped");
});
connect(peripheralId)
Attempts to connect to a peripheral. In many case if you can't connect you have to scan for the peripheral before.
Returns a Promise
object.
In iOS, attempts to connect to a peripheral do not time out (please see Apple's doc), so you might need to set a timer explicitly if you don't want this behavior.
Arguments
peripheralId
- String
- the id/mac address of the peripheral to connect.
Examples
BleManager.connect("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
.then(() => {
console.log("Connected");
})
.catch((error) => {
console.log(error);
});
disconnect(peripheralId, force)
Disconnect from a peripheral.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral to disconnect.force
- boolean
- [Android only] defaults to true, if true force closes gatt
connection and send the BleManagerDisconnectPeripheral
event immediately to Javascript, else disconnects the
connection and waits for disconnected state
to
close the gatt connection
and then sends the BleManagerDisconnectPeripheral to the
Javascript
Examples
BleManager.disconnect("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
.then(() => {
console.log("Disconnected");
})
.catch((error) => {
console.log(error);
});
enableBluetooth() [Android only]
Create the request to the user to activate the bluetooth.
Returns a Promise
object.
Examples
BleManager.enableBluetooth()
.then(() => {
console.log("The bluetooth is already enabled or the user confirm");
})
.catch((error) => {
console.log("The user refuse to enable bluetooth");
});
checkState()
Force the module to check the state of BLE and trigger a BleManagerDidUpdateState event.
Examples
BleManager.checkState();
startNotification(peripheralId, serviceUUID, characteristicUUID)
Start the notification on the specified characteristic, you need to call retrieveServices
method before.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.
Examples
BleManager.startNotification(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"
)
.then(() => {
console.log("Notification started");
})
.catch((error) => {
console.log(error);
});
startNotificationUseBuffer(peripheralId, serviceUUID, characteristicUUID, buffer) [Android only]
Start the notification on the specified characteristic, you need to call retrieveServices
method before. The buffer will collect a number or messages from the server and then emit once the buffer count it reached. Helpful to reducing the number or js bridge crossings when a characteristic is sending a lot of messages.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.buffer
- Integer
- a number of message to buffer prior to emit for the characteristic.
Examples
BleManager.startNotification(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
1234
)
.then(() => {
console.log("Notification started");
})
.catch((error) => {
console.log(error);
});
stopNotification(peripheralId, serviceUUID, characteristicUUID)
Stop the notification on the specified characteristic.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.
read(peripheralId, serviceUUID, characteristicUUID)
Read the current value of the specified characteristic, you need to call retrieveServices
method before.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.
Examples
BleManager.read(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"
)
.then((readData) => {
console.log("Read: " + readData);
const buffer = Buffer.Buffer.from(readData);
const sensorData = buffer.readUInt8(1, true);
})
.catch((error) => {
console.log(error);
});
write(peripheralId, serviceUUID, characteristicUUID, data, maxByteSize)
Write with response to the specified characteristic, you need to call retrieveServices
method before.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.data
- Byte array
- the data to write.maxByteSize
- Integer
- specify the max byte size before splitting message
Data preparation
If your data is not in byte array format you should convert it first. For strings you can use convert-string
or other npm package in order to achieve that.
Install the package first:
npm install convert-string
Then use it in your application:
import { stringToBytes } from "convert-string";
const data = stringToBytes(yourStringData);
Feel free to use other packages or google how to convert into byte array if your data has other format.
Examples
BleManager.write(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
data
)
.then(() => {
console.log("Write: " + data);
})
.catch((error) => {
console.log(error);
});
writeWithoutResponse(peripheralId, serviceUUID, characteristicUUID, data, maxByteSize, queueSleepTime)
Write without response to the specified characteristic, you need to call retrieveServices
method before.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUID
- String
- the UUID of the service.characteristicUUID
- String
- the UUID of the characteristic.data
- Byte array
- the data to write.maxByteSize
- Integer
- (Optional) specify the max byte sizequeueSleepTime
- Integer
- (Optional) specify the wait time before each write if the data is greater than maxByteSize
Data preparation
If your data is not in byte array format check info for the write function above.
Example
BleManager.writeWithoutResponse(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
data
)
.then(() => {
console.log("Writed: " + data);
})
.catch((error) => {
console.log(error);
});
Read the current value of the RSSI.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.
Examples
BleManager.readRSSI("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
.then((rssi) => {
console.log("Current RSSI: " + rssi);
})
.catch((error) => {
console.log(error);
});
requestConnectionPriority(peripheralId, connectionPriority) [Android only API 21+]
Request a connection parameter update.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.connectionPriority
- Integer
- the connection priority to be requested, as follows:
- 0 - balanced priority connection
- 1 - high priority connection
- 2 - low power priority connection
Examples
BleManager.requestConnectionPriority("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX", 1)
.then((status) => {
console.log("Requested connection priority");
})
.catch((error) => {
console.log(error);
});
requestMTU(peripheralId, mtu) [Android only API 21+]
Request an MTU size used for a given connection.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.mtu
- Integer
- the MTU size to be requested in bytes.
Examples
BleManager.requestMTU("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX", 512)
.then((mtu) => {
console.log("MTU size changed to " + mtu + " bytes");
})
.catch((error) => {
console.log(error);
});
retrieveServices(peripheralId[, serviceUUIDs])
Retrieve the peripheral's services and characteristics.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.serviceUUIDs
- String[]
- [iOS only] only retrieve these services.
Examples
BleManager.retrieveServices("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX").then(
(peripheralInfo) => {
console.log("Peripheral info:", peripheralInfo);
}
);
refreshCache(peripheralId) [Android only]
refreshes the peripheral's services and characteristics cache
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.
Examples
BleManager.refreshCache("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
.then((peripheralInfo) => {
console.log("cache refreshed!");
})
.catch((error) => {
console.error(error);
});
getConnectedPeripherals(serviceUUIDs)
Return the connected peripherals.
Returns a Promise
object.
Arguments
serviceUUIDs
- Array of String
- the UUIDs of the services to looking for.
Examples
BleManager.getConnectedPeripherals([]).then((peripheralsArray) => {
console.log("Connected peripherals: " + peripheralsArray.length);
});
createBond(peripheralId,peripheralPin) [Android only]
Start the bonding (pairing) process with the remote device. If you pass peripheralPin(optional), bonding will be auto(without manual entering pin)
Returns a Promise
object. The promise is resolved when either new bond successfully created
or bond already existed
, otherwise it will be rejected.
Examples
BleManager.createBond(peripheralId)
.then(() => {
console.log("createBond success or there is already an existing one");
})
.catch(() => {
console.log("fail to bond");
});
removeBond(peripheralId) [Android only]
Remove a paired device.
Returns a Promise
object.
Examples
BleManager.removeBond(peripheralId)
.then(() => {
console.log("removeBond success");
})
.catch(() => {
console.log("fail to remove the bond");
});
getBondedPeripherals() [Android only]
Return the bonded peripherals.
Returns a Promise
object.
Examples
BleManager.getBondedPeripherals([]).then((bondedPeripheralsArray) => {
console.log("Bonded peripherals: " + bondedPeripheralsArray.length);
});
getDiscoveredPeripherals()
Return the discovered peripherals after a scan.
Returns a Promise
object.
Examples
BleManager.getDiscoveredPeripherals([]).then((peripheralsArray) => {
console.log("Discovered peripherals: " + peripheralsArray.length);
});
removePeripheral(peripheralId) [Android only]
Removes a disconnected peripheral from the cached list.
It is useful if the device is turned off, because it will be re-discovered upon turning on again.
Returns a Promise
object.
Arguments
peripheralId
- String
- the id/mac address of the peripheral.
isPeripheralConnected(peripheralId, serviceUUIDs)
Check whether a specific peripheral is connected and return true
or false
.
Returns a Promise
object.
Examples
BleManager.isPeripheralConnected(
"XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
[]
).then((isConnected) => {
if (isConnected) {
console.log("Peripheral is connected!");
} else {
console.log("Peripheral is NOT connected!");
}
});
setName(name) [Android only]
Create the request to set the name of the bluetooth adapter. (https://developer.android.com/reference/android/bluetooth/BluetoothAdapter#setName(java.lang.String))
Returns a Promise
object.
Examples
BleManager.setName("INNOVEIT_CENTRAL")
.then(() => {
console.log("Name set successfully");
})
.catch((error) => {
console.log("Name could not be set");
});
Events
BleManagerStopScan
The scanning for peripherals is ended.
Arguments
Examples
bleManagerEmitter.addListener("BleManagerStopScan", () => {
});
BleManagerDidUpdateState
The BLE change state.
Arguments
state
- String
- the new BLE state ('on'/'off').
Examples
bleManagerEmitter.addListener("BleManagerDidUpdateState", (args) => {
});
BleManagerDiscoverPeripheral
The scanning find a new peripheral.
Arguments
id
- String
- the id of the peripheralname
- String
- the name of the peripheralrssi
- Number
- the RSSI valueadvertising
- JSON
- the advertising payload, here are some examples:
isConnectable
- Boolean
serviceUUIDs
- Array of String
manufacturerData
- JSON
- contains the raw bytes
and data
(Base64 encoded string)serviceData
- JSON
- contains the raw bytes
and data
(Base64 encoded string)txPowerLevel
- Int
Examples
bleManagerEmitter.addListener("BleManagerDiscoverPeripheral", (args) => {
});
BleManagerDidUpdateValueForCharacteristic
A characteristic notify a new value.
Arguments
value
— Array
— the read valueperipheral
— String
— the id of the peripheralcharacteristic
— String
— the UUID of the characteristicservice
— String
— the UUID of the characteristic
Event will only be emitted after successful startNotification
.
Example
import { bytesToString } from "convert-string";
import { NativeModules, NativeEventEmitter } from "react-native";
const BleManagerModule = NativeModules.BleManager;
const bleManagerEmitter = new NativeEventEmitter(BleManagerModule);
async function connectAndPrepare(peripheral, service, characteristic) {
await BleManager.connect(peripheral);
await BleManager.retrieveServices(peripheral);
await BleManager.startNotification(peripheral, service, characteristic);
bleManagerEmitter.addListener(
"BleManagerDidUpdateValueForCharacteristic",
({ value, peripheral, characteristic, service }) => {
const data = bytesToString(value);
console.log(`Received ${data} for characteristic ${characteristic}`);
}
);
}
BleManagerConnectPeripheral
A peripheral was connected.
Arguments
peripheral
- String
- the id of the peripheralstatus
- Number
- [Android only] connect reasons
BleManagerDisconnectPeripheral
A peripheral was disconnected.
Arguments
BleManagerPeripheralDidBond
A bond with a peripheral was established
Arguments
Object with information about the device
BleManagerCentralManagerWillRestoreState [iOS only]
This is fired when centralManager:WillRestoreState:
is called (app relaunched in the background to handle a bluetooth event).
Arguments
peripherals
- Array
- an array of previously connected peripherals.
For more on performing long-term bluetooth actions in the background:
iOS Bluetooth State Preservation and Restoration
iOS Relaunch Conditions
BleManagerDidUpdateNotificationStateFor [iOS only]
The peripheral received a request to start or stop providing notifications for a specified characteristic's value.
Arguments
peripheral
- String
- the id of the peripheralcharacteristic
- String
- the UUID of the characteristicisNotifying
- Boolean
- Is the characteristic notifying or notdomain
- String
- [iOS only] error domaincode
- Number
- [iOS only] error code