Headset Proximity feature in the Spokes SDK allows application developers to query the proximity of their Bluetooth headset with respect to their Bluetooth USB dongle that is connected to the PC.

Spokes SDK developers can access the IHostCommandExt interface by casting the HostCommand property in IDevice. If it returns a valid interface then you can call GetProximity() to request the proximity. If the request is successful GetProximity() will return true otherwise false. The proximity response from the headset will be reported to the host as an async event so application developers have to register for Proximity events by registering either  for HeadsetStateChanged event exposed in DeviceListener property of IDevice or by registering for the HeadsetStateChanged event exposed in IDeviceEventsExt. Developers can access the IDeviceEventsExt interface by casting the DeviceEvents property in IDevice. If it returns a valid interface then you can register for HeadsetstateChanged event

Following interfaces IHostCommandExt, IDeviceEventsExt, IDeviceListenerEvents will expose proximity events and a way to request proximity as part of the Spokes SDK. These interfaces can be accessed by applications that directly interface with the device manager or plug-ins that interface with the Spokes SDK.

IHostCommandExt Interface

    publicinterfaceIHostCommandExt : IHostCommand, IExtendedVersion

{

        …

        bool GetProximity();

        bool EnableProximity(bool bEnable);

}

Method: bool GetProximity()

GetProximity() will send a request to the Plantronics device connected to the USB to get the proximity of the headset. This function returns true if the request is successful otherwise false. On a device that doesn’t support proximity the SDK will throw a DeviceManagerException and applications should handle that exception.

Method: bool EnableProximity(bool bEnable)

EnableProximity() will send a command to the device to enable or disable Proximity reporting from the headset. bEnable = true, enables proximity reporting and bEnable=false disables proximity reporting.

IDeviceEventsExt Interface

     publicinterfaceIDeviceEventsExt : IDeviceEvents

{

       …..

        eventHeadsetStateEventHandler HeadsetStateChanged;       

  }

IDeviceListenerEvents Interface

    publicinterfaceIDeviceListenerEvents

{

        //Headset : Covers Corded, Cordless headsets events

        eventDeviceListenerEventHandler HeadsetButtonPressed;

        eventDeviceListenerEventHandler HeadsetStateChanged;

        //Base: Covers Base, Hub, Handset events

        eventDeviceListenerEventHandler BaseButtonPressed;

        eventDeviceListenerEventHandler BaseStateChanged;

        //ATD: Covers Mobile, PSTN and other ATD events

        eventDeviceListenerEventHandler ATDStateChanged;

}

Code snippets:

Sample 1: Requesting Headset Proximity

      privatevoid radBProximity_Click(object sender, EventArgs e)

      {

            try

            {

                if (m_command != null)

                {

                    m_command.GetProximity();

                }

            }

            catch (DeviceManagerException ex)

            {

                MessageBox.Show(ex.Message, "Spokes DM SDK");

            }

        }

Sample 2: Registering for  Headset Proximity via IDeviceEventExt:

IDevice m_device = null;

IDeviceEventsExt m_events = null;

IHostCommandExt m_command = null;

//Get a valid device and init m_device

….

//Cast HostCommand and init m_command and m_events

m_command = device.HostCommand asIHostCommandExt;

m_events = device.DeviceEvents asIDeviceEventsExt;

//Register for HeadsetStateChanged event on Attach()to the device

if (m_events != null)

{

   m_events.HeadsetStateChanged += events_HeadsetStateChanged;      

}

//UnRegister for HeadsetStateChanged event on Detach() to the device

if (m_events != null)

{

   m_events.HeadsetStateChanged -= events_HeadsetStateChanged;      

}

//Event handler for HeadsetStateChanged

void events_HeadsetStateChanged(object sender, HeadsetStateEventArgs e)

{           

   UpdateHeadsetState(e);    

}

privatevoid UpdateHeadsetState(HeadsetStateEventArgs e)

{           

            StringBuilder strB = newStringBuilder();

            strB.Append("Device Event: ");

            if (e.State == HeadsetState.Proximity)

            {

                strB.Append(String.Format("Headset Proximity received. (Proximity = {0})", e.Proximity)); 

            }

            else

                strB.Append(String.Format("Headset state changed. ({0})", e.State.ToString())); 

            strB.AppendLine();

           //Update UI after marshalling to Main GUI thread

richTextBoxTrace.AppendText(strB.ToString());

}

Sample 3: Registering for Headset Proximity via IDeviceListenerEvents

IDevice m_device = null;

IHostCommandExt m_command = null;

IDeviceListener m_devListener = null;

//Get a valid device and init m_device

….

//Cast HostCommand and init m_command and m_devListener

m_command = device.HostCommand asIHostCommandExt;

m_devListener = device.DeviceListener asIDeviceListener;

//Register for HeadsetStateChanged event on Attach()to the device

if (m_devListener != null)

{

m_devListener.HeadsetStateChanged += listenerEvents_HeadsetStateChanged;

}

//UnRegister for HeadsetStateChanged event on Detach() to the device

if (m_devListener != null)

{

m_devListener.HeadsetStateChanged -= listenerEvents_HeadsetStateChanged;

}

//Event handler for HeadsetStateChanged

void listenerEvents_HeadsetStateChanged(object sender, DeviceListenerEventArgs e)

{

            UpdateMainThreadUI(String.Format("Headset state Changed {0}", e.HeadsetStateChange.ToString().ToUpper()));

}