java.lang.InstantiationException: class has no zero argument constructor

Question

I am trying to use a BroadcastReceiver as an inner class to track the network state but I got the exception in the title. What should I do to fix this problem?

public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        final ConnectivityManager connMgr = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);

        final android.net.NetworkInfo wifi = connMgr.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
        final android.net.NetworkInfo mobile = connMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

        if (wifi.isAvailable() || mobile.isAvailable()) {
            setupData();
            Log.d("Netowk Available ", "Flag No 1");
        }
    }
}

Answer 1

Your

inner Broadcast receiver must be static ( to be registered through Manifest)

OR

Non-static broadcast receiver must be registered and unregistered inside the Parent class

for this.

I was using an Inner broadcast reciver, without registering it within the class. Either make it static and register in Manifest , or Make it non static and register and unregister inside the parent class .

Answer 2

A non-static inner class cannot be registered via the AndroidManifest.xml. You can either:

Register it dynamically as outlined in this thread, and remove the empty constructor.

Or,

Make your inner class static, and register it in the AndroidManifext.xml.

Answer 3

just make your Receiver Class static like:

public [static] class ReceiverClass extends BroadcastReceiver

Answer 4

e~~I just meet that problem,and I refactor the class NetworkChangeReceiver to an another place