question: public void addListener ( DiscoveryManagerListener listener ) { for ( ConnectableDevice device : compatibleDevices . values ( ) ) { listener . onDeviceAdded ( this , device ) ; } discoveryListeners . add ( listener ) ; }
target:  Listener which should receive discovery updates. It is not necessary to set this listener property unless you are implementing your own device picker. Connect SDK provides a default DevicePicker which acts as a DiscoveryManagerListener, and should work for most cases. If you have provided a capabilityFilters array, the listener will only receive update messages for ConnectableDevices which satisfy at least one of the CapabilityFilters. If no capabilityFilters array is provided, the listener will receive update messages for all ConnectableDevice objects that are discovered.