Mobile_Stack

Getting Started with the Mobile Stack

The Mobile Stack of Xamarin.Robotics makes communication with the Micro Stack easy by providing a cross-platform Bluetooth Low-Energy (BLE) API.

Installing the Mobile Component

The Mobile Stack can be installed as a component, available in the Xamarin Component Store:

To install into your app, double click on the Components folder and search for Robotics. Click on it and then choose Add to App.

Integrating BLE

The following code can be seen in action in the BLE Explorer sample app included in the component. It's also availabe here. The following is an overview of working with the API, but for a full understanding of how to use it, make sure to check out the sample app.

Get a Reference to the Adapter

In order to connect to BLE devices, the first thing that you'll need to do is get a reference to the Adapter. The Adapter gives you access to BLE communication functions. A single adapter is used across your entire app, and is available as the static Current property on the Adapter class:

App.SetAdapter (Adapter.Current);

Enumerating Devices

Once you have your adapter, you can start device scanning via StartScanningForDevice and pass an empty GUID if you don't want to scan for any particular device, but instead want to enumerate them all:

adapter.StartScanningForDevices(Guid.Empty);

Connecting to a Device

An IDevice reference is passed every time a device is discovered:

adapter.DeviceDiscovered += (object sender, DeviceDiscoveredEventArgs e) => {
	Device.BeginInvokeOnMainThread(() => {
		devices.Add (e.Device);
	});
};

To connect to that device, simply call ConnectToDevice on the adapter and pass the IDevice reference:

adapter.ConnectToDevice (device); 

Enumerating Services

Once the Device is connected, you can enumerate the services on it by calling DiscoverServices.

adapter.DeviceConnected += (s, e) => {
	device = e.Device; // do we need to overwrite this?

	// when services are discovered
	device.ServicesDiscovered += (object se, EventArgs ea) => {
		Debug.WriteLine("device.ServicesDiscovered");
		//services = (List<IService>)device.Services;
		if (services.Count == 0)
			Device.BeginInvokeOnMainThread(() => {
				foreach (var service in device.Services) {
					services.Add(service);
				}
			});
	};
	// start looking for services
	device.DiscoverServices ();

};

Enumerating Characteristics

You can enumerate the characteristics for a service by calling DiscoverCharacteristics on the Service itself:

// when characteristics are discovered
service.CharacteristicsDiscovered += (object sender, EventArgs e) => {
	Debug.WriteLine("service.CharacteristicsDiscovered");
	if (characteristics.Count == 0)
		Device.BeginInvokeOnMainThread(() => {
			foreach (var characteristic in service.Characteristics) {
				characteristics.Add(characteristic);
			}
		});
};

// start looking for characteristics
service.DiscoverCharacteristics ();