Discover & Connect to Device

Initial setup

Your view controller should implement delegate/listener methods for Connect SDK's DevicePicker and ConnectableDevice classes. These methods will give you the ability to respond to device selection, ready, disconnect, and error states.

public class MainActivity extends Activity implements ConnectableDeviceListener {
}
It is helpful to retain local references to both the DiscoveryManager and the ConnectableDevice objects. In most use cases, these two classes will serve to provide most of the functionality required.

As soon as your app loads, you should instantiate the DiscoveryManager singleton and start discovery. As different devices can take a wide range of time to be discovered, it is recommended that discovery start as soon as possible after app launch.

private DiscoveryManager mDiscoveryManager;
private ConnectableDevice mDevice;
This can be initialized in the the Application class or in your Activity.  You should always use getApplicationContext() since the DiscoveryManager will likely hold onto this object longer than the life of a single Activity.
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    
    DiscoveryManager.init(getApplicationContext());

    // This step could even happen in your app's delegate
    mDiscoveryManager = DiscoveryManager.getInstance();
    mDiscoveryManager.start();
}

Discovery & device selection

In many cases, your user will want to select one device from a list of many. You should present the DevicePicker to the user to receive their selection. The DevicePicker includes a dynamic listing of all devices that have been discovered on the network.

private void showImage() {
    DevicePicker devicePicker = new DevicePicker(this);
    AlertDialog dialog = devicePicker.getPickerDialog("Show Image", selectDevice);
    dialog.show();
}

Once the user has selected a device, you should immediately register for events from that device and then call the connect method.

AdapterView.OnItemClickListener selectDevice = new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView adapter, View parent, int position, long id) {
        mDevice = (ConnectableDevice) adapter.getItemAtPosition(position);
        mDevice.addListener(deviceListener);
        mDevice.connect();
    }
}

Capability Filtering

If your app is making use of certain device capabilities (media playback/controls, web app launching, etc), it is strongly recommended that you create filters with this information for DiscoveryManager.

Devices that are discovered & shown in the picker will be guaranteed to have the set of capabilities that you have provided. This will prevent your users from selecting a device that has not yet acquired all of its protocols.

CapabilityFilter videoFilter = new CapabilityFilter(
		MediaPlayer.Display_Video, 
		MediaControl.Any, 
		VolumeControl.Volume_Up_Down
);

CapabilityFilter imageCapabilities = new CapabilityFilter(
		MediaPlayer.Display_Image
);

DiscoveryManager.getInstance().setCapabilityFilters(videoFilter, imageCapabilities);
Check out the article on capabilities for more depth on this topic.