Android WiFi Direct WIFI_P2P_PEERS_CHANGED_ACTION never received

Question

I'm trying to make a multiplayer game for Android via WiFi direct. I followed the instructions on http://developer.android.com/training/connect-devices-wirelessly/wifi-direct.html in order to connect to devices.

The ActionListener i use with discoverPeers() returns successfully, but then i never receive the WIFI_P2P_PEERS_CHANGED_ACTION intent upon which i would call requestPeers(). Strangely when i go into WiFi direct system settings on one device, the other is able to successfully detect it through my app. Do i need to make my device discoverable in my app or something? I haven't found anything to indicate that in the Android developer resources regarding WiFi P2P. There is WiFi direct for service discovery, but that's something else entirely, isn't it?

Answer 1

Add WIFI_P2P_PEERS_CANGED_ACTION into your broadcast receiver intent-filter.

Answer 2

There are two factors contributing to the problem:

1. The event never occurred and not broadcast to others.
2. Although the event occurred, the intent filter does not catch it.

In my case, I found that the receiver does not get the event properly. the reason was because I didn't registerReceiver to the intent filter properly.

after I do

intentFilter.addAction(WifiP2PManager.WIFI_P2P_PEERS_CHANGED_ACTION), 

I didn't do

ct.registerReceiver(bReceiver, intentFilter).

ct is activity or context, and bReceiver is WifiDirectBroadcastReceiver. I firstly wrote

ct.registerReceiver(bReceiver, intentFilter),

but, it was not executed properly.

Answer 3

You have to find devices under Settings/Wifi/Direct Wifi/Available devices

Answer 4

You need to run discoverPeers() on other devices as well.
Now you will receive the WIFI_P2P_PEERS_CHANGED_ACTION intent