Android: How to monitor WiFi signal strength
android, networking
Solution
First, make sure you have `<uses-permission>` for `ACCESS_WIFI_STATE` in your manifest.
Second, I'm not sure about notifications for a single connection, but to get notifications of everything the radio is seeing, you can start a scan:
wifi.startScan();
Next, when I've received successful results, I used `WifiManager.SCAN_RESULTS_AVAILABLE_ACTION` in the `IntentFilter`.
Then, in the receiver, I use `getScanResults()` from the `WifiManager` object, which also contains the signal strength.
For stopping it this way, you simply call to `unregisterRecever()` (so you'll want to keep it around for referencing). I haven't tested myself to see if my scanning code can be modified to just check the current connection, but I do know I got plenty of results -- Wi-Fi signals change frequently and quickly. I suppose for monitoring a single connection, you can also just filter the scan results and look for the one the device is currently connected to.
I hope this helps a little.
Problem
I would receive notifications when signal strength changes. I tried to create the following method and call it in the onCreate(): ``` private void initializeWiFiListener(){ Log.i(TAG, "executing initializeWiFiListener"); String connectivity_context = Context.WIFI_SERVICE; final WifiManager wifi = (WifiManager)getSystemService(connectivity_context); if(!wifi.isWifiEnabled()){ if(wifi.getWifiState() != WifiManager.WIFI_STATE_ENABLING){ wifi.setWifiEnabled(true); } } registerReceiver(new BroadcastReceiver(){ @Override public void onReceive(Context context, Intent intent) { WifiInfo info = wifi.getConnectionInfo(); //TODO: implement methods for action handling } }, new IntentFilter(WifiManager.RSSI_CHANGED_ACTION)); } ``` I would appreciate if anyone could check if the method is written correctly. I tried to run the app, but haven't received any notifications and am not sure whether it is because the signal strength might be constant in the place I run debug or it is because something is missing. Thanks!