Android 8.0 Oreo wifi list not getting

Question

On Android 8.0, not getting wifi list using wifiManager, below API level 26 I am getting the list.

This function returns the WifiManager Object

public static WifiManager getWifiManager(Context context) {
        WifiManager wifiManager = null;
        try {

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

        } catch (NullPointerException e) {
            e.printStackTrace();
        }

        return wifiManager;
    }

This function returns the wifi list

public static List<ScanResult> getWifiScanResults(Boolean sorted, Context context) {
    WifiManager wifiManager = NetworkUtil.getWifiManager(context);
    List<ScanResult> wifiList = wifiManager.getScanResults();

    //Remove results with empty ssid
    List<ScanResult> wifiListNew = new ArrayList<>();
    for (ScanResult scanResult : wifiList) {
        if (!scanResult.SSID.equals(""))
            wifiListNew.add(scanResult);
    }
    wifiList.clear();
    wifiList.addAll(wifiListNew);

         return wifiList;
}

I had registered the BroadcastReceiver

WiFiMainActivity.this.registerReceiver(receiverWifi, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));

and here is the startScan() Method

   public static void startScan(Context context) {
        WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
        wifiManager.startScan();
    }

User having following permission

  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />

Not able to track the bug on android 8.0 Oreo, is there any other permission that I am missing.

Answer 1

Since in Android 8 was introduced the background execution limitation most of BroadcastReceiver actions registered in Manifest will be no longer sent nor received except these ones.

Yes, you are registering it through your Context but maybe your code is wrong.

You should register it through your Application Context instead of your Activity Context to avoid memory leaks. Also, try creating a void IntentFilter and adding your action afterwards. This code is working fine in my application with targetSdkVersion 26+ in Android 8 Oreo (Nexus 5X).

IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("android.net.wifi.SCAN_RESULTS");
context.registerReceiver(new YourBroadcastReceiver(), intentFilter);

Hope this help.