NsdManger.DiscoveryListener(): how to flush the cache
<p>I have device which will broadcast itself once connected to the AP (through mDNS). 
But the strange thing is :</p>

<p><code>even the device has been plug out for a few 10 minutes, when I retsart the app (so restart the NsdManager too )the Android API NsdManger.DiscoveryListener() still cannot find it's not available anymore (onServiceFound() raise immediately ).</code> </p>

<p>it looks like the device's info has been cached by the system.  Does anyone know how the NsdManger.DiscoveryListener() works and how to force it to flush the cache? Thanks. </p>
