NeatLE

NeatLE is an Android BTLE (Bluetooth low energy) support library that simplifies management of BTLE connections, subscriptions, devices and operations. It provides a single entry point for all BTLE related operations.

Features

Monitor a connection to a BTLE device.
Send read / write commands and receive responses.
Subscribe to characteristics and get notified of changes.

Installation

Include the NeatLE library in your Android project as a Gradle dependency:

dependencies {
    compile 'si.inova:neatle:X.Y.Z'
}

Replace X.Y.Z above with latest version: Maven Central

Examples

Scan for nearby devices

Scanner can be used to scan for all nearby BTLE devices that advertise specific service.

if (ContextCompat.checkSelfPermission(context,
        Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
    // We cannot scan as we do not have location permission
    // TODO notify user

    return;
}

// Scan for devices that can report battery status
UUID batteryService = Neatle.createUUID(0x180f);

ScanBuilder builder = Neatle.createScannerBuilder();
builder.addServiceUUID(batteryService);

builder.setNewDeviceFoundListener(new Scanner.NewDeviceFoundListener() {
    @Override
    public void onNewDeviceFound(ScanEvent e) {
        System.out.println("Device " + e.getDevice() + " found!");
    }
});

scanner = builder.build();
scanner.startScanning(context);

...

scanner.stopScanning();

Monitor for connections:

A ConnectionMonitor tries to connect to a specific BTLE device, and if configured with setKeepAlive(true), will try to maintain that connection until the monitor is stopped. The ConnectionStateListener will be notified of any changes to the connection, (e.g. device connected / disconnected).

ConnectionMonitor monitor =
        Neatle.createConnectionMonitor(context, Neatle.getDevice("00:11:22:33:44:55"));
monitor.setOnConnectionStateListener(new ConnectionStateListener() {
    @Override
    public void onConnectionStateChanged(Connection connection, int newState) {
        if(connection.isConnected()){
            // The device has connected
        }
    }
});
monitor.start();

Create an operation:

An Operation is a series of read / write commands that can be executed for a specific BTLE device. It can have multiple read and write operations, that will be executed on the device sequentially.

An operation can also be executed more than once.

Read operation

BluetoothDevice device = Neatle.getDevice("00:11:22:33:44:55");
UUID batteryService = Neatle.createUUID(0x180f);
final UUID batteryCharacteristic = Neatle.createUUID(0x2a19);

Operation operation = Neatle.createOperationBuilder(context)
        .read(batteryService, batteryCharacteristic)
        .onFinished(new SimpleOperationObserver() {
            @Override
            public void onOperationFinished(Operation op, OperationResults results) {
                if(results.wasSuccessful()){
                    int battery = results.getResult(batteryCharacteristic).getValueAsInt();
                }
            }
        })
        .build(device);
operation.execute();

Write operation

BluetoothDevice device = Neatle.getDevice("00:11:22:33:44:55");
UUID serviceToWrite = ...
final UUID characteristicToWrite = ...
byte[] dataToWrite = ...

InputSource inputSource = new ByteArrayInputSource(dataToWrite);

Operation operation = Neatle.createOperationBuilder(context)
        .write(serviceToWrite, characteristicToWrite, inputSource)
        .onFinished(new SimpleOperationObserver() {
            @Override
            public void onOperationFinished(Operation op, OperationResults results) {
                if (results.wasSuccessful()) {
                    System.out.println("Write was successful!");
                } else {
                    System.out.println("Write failed! ");
                }
            }
        })
        .build(device);
operation.execute();

Create a subscription:

A Subscription listens for notification events on a specific service for a specific characteristic on the BTLE device, and reports them back to the caller.

BluetoothDevice device = Neatle.getDevice("00:11:22:33:44:55");
UUID batteryService = Neatle.createUUID(0x180f);
UUID batteryCharacteristic = Neatle.createUUID(0x2a19);

CharacteristicSubscription subscription =
        Neatle.createSubscription(context, device, batteryService, batteryCharacteristic);
subscription.setOnCharacteristicsChangedListener(new CharacteristicsChangedListener() {
    @Override
    public void onCharacteristicChanged(CommandResult change) {
        if (change.wasSuccessful()) {
            int batteryLevel = change.getValueAsInt();
        }
    }
});
subscription.start();

Note: An active subscription will keep a ConnectionMonitor with setKeepAlive(false) (the default setting) alive.

Permissions

The following permission are required by NeatLE (and are already defined in it's manifest):

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

The ACCESS_COARSE_LOCATION permission is considered dangerous on Android 6.0 (23) and up, and should be requested manually by the developer, before running NeatLE.

License

MIT License

Copyright (c) 2017 Inova IT

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.`

inovait / neatle

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