chrome/common/extensions/docs/templates/intros/dial.html

   1 <p>The <code>chrome.dial</code> API is backed by a service that multicasts
   2 discovery requests on the local network to discover DIAL-capable devices and
   3 maintains a list of devices that have responded.  Adding an onDeviceList
   4 listener causes the service to periodically issue discovery requests to maintain
   5 the device list. (No polling is done when there are no onDeviceList listeners.)
   6 </p>
   7
   8 <p>The onDeviceList event is fired when discovery respnses are received and in
   9 other circumstances; see the documentation for onDeviceList.</p>
  10
  11 <p>The client can request that network discovery can be done immediately by
  12 invoking discoverNow() which is useful for presenting the user with an
  13 updated list of devices.</p>
  14
  15 <p>On-demand use (updates when discoverNow() is called):
  16 <pre>
  17 chrome.dial.onDeviceList.addListener(function (list) { updateMenu(list); });
  18 chrome.dial.discoverNow();
  19 </pre>
  20 (Remember to remove the listener when the menu closes.)</p>
  21
  22 <p>Background use (updates only when periodic polling happens):</p>
  23
  24 <pre>
  25 var myList;
  26 chrome.dial.onDeviceList.addListener(function (list) { myList = list; });
  27 </pre>
  28
  29 <p>These can be combined to poll for devices to prime the device menu, then
  30 refresh the menu when it is displayed.</p>