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androidnetwork-programmingandroid-wifi

Find available wifi connections in Android

I am trying to create a help wizard to recover from bad network connections in the app. One test case I hope to handle is the case where an end user has WiFi turned off, WiFi is available, and the mobile network is slower than the WiFi network. In this event, I want to be able to (1) discover the available WiFi network s, (2) find the WiFi network speed, (3) Compare its speed to the mobile network speed, (4) digest the user changes to the faster network.

For this to work, I need to know how to programmatically get information on available connections. Is that something we can do? If so, how can we tell what connections are available? Thanks in advance.

Solution

  • Task-1: Discover the available WiFi network

    This can be done by getting WifiManager's instance from the System.

    WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
wifiManager.getScanResults();

// The above is an async call and will results are available System will broadcast `SCAN_RESULTS_AVAILABLE` intent and you need to set a `BroadCastReceiver` for it.

// And get the results like this 

List<ScanResult> results = wifiManager.getScanResults();

    Task-2&3: find the network speed

    This link gives an answer to your question about how to get network speeds of wifi and mobile network

    Wifi:

    WifiManager wifiManager = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);
int linkSpeed = wifiManager.getConnectionInfo().getRssi();

    In case of mobile it should work:

    TelephonyManager telephonyManager =        (TelephonyManager)this.getSystemService(Context.TELEPHONY_SERVICE);
CellInfoGsm cellinfogsm = (CellInfoGsm)telephonyManager.getAllCellInfo().get(0);
CellSignalStrengthGsm cellSignalStrengthGsm = cellinfogsm.getCellSignalStrength();
cellSignalStrengthGsm.getDbm();
Then You should compare this signal levels and if WIFI signal is better keep it turn on, but if mobile is better disconnect wifi

    Task-4: Switching to the option with higher speed

    In Android by default, if wifi is on and connected then your mobile network won't be used. Hence to use mobile data you must either disconnect from all available wifi-networks or switch off the wifi.

    I will also suggest you to read link this, this and this for getting more information on how to get connection speed.