ACTION intent received twice when Wifi connected

In my app I have a BroadcastReceiver that is launched as a component through a <receiver> tag, filtering android.net.conn.CONNECTIVITY_CHANGE intents.

My goal is simply to know when a Wifi connection was established, so what I am doing in onReceive() is this:

NetworkInfo networkInfo = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if(networkInfo.getType() == ConnectivityManager.TYPE_WIFI && networkInfo.isConnected()) {
    // Wifi is connected
}

It works fine, but I always seem to get two identical intents within about one second when a Wifi connection is established. I tried to look at any info I could get from the intent, the ConnectivityManager and WifiManager , but I can't find anything that distinguishes the two intents.

Looking at the log, there is at least one other BroadcastReceiver that also receives the two identical intents.

It is running on a HTC Desire with Android 2.2

Any idea why I seem to get a "duplicated" intent when Wifi connects or what the difference between the two might be?

---

After a lot of googling and debugging, I believe this is the correct way to determine if Wifi has connected or disconnected.

The onReceive() method in the BroadcastReceiver:

public void onReceive(final Context context, final Intent intent) {

if(intent.getAction().equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) {
    NetworkInfo networkInfo =
        intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
    if(networkInfo.isConnected()) {
        // Wifi is connected
        Log.d("Inetify", "Wifi is connected: " + String.valueOf(networkInfo));
    }
} else if(intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
    NetworkInfo networkInfo =
        intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
    if(networkInfo.getType() == ConnectivityManager.TYPE_WIFI &&
        ! networkInfo.isConnected()) {
        // Wifi is disconnected
        Log.d("Inetify", "Wifi is disconnected: " + String.valueOf(networkInfo));
    }
}
}

Together with the following receiver element in AndroidManifest.xml

<receiver android:name="ConnectivityActionReceiver"
    android:enabled="true" android:label="ConnectivityActionReceiver">
    <intent-filter>
        <action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
        <action android:name="android.net.wifi.STATE_CHANGE"/>
    </intent-filter>
</receiver>

Some explanation:

When only considering ConnectivityManager.CONNECTIVITY_ACTION , I always get two intents containing identical NetworkInfo instances (both getType() == TYPE_WIFI and isConnected() == true) when Wifi connects - the issue described in this question.

When only using WifiManager.NETWORK_STATE_CHANGED_ACTION , there is no intent broadcasted when Wifi disconnects, but two intents containing different NetworkInfo instances, allowing to determine one event when Wifi is connected.

NOTE: I've received one single crash report (NPE) where the intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO) returned null. So, even if it seems to be extremely rare to happen, it might be a good idea to add a null check.

Cheers, Torsten

---

If you're listening on WifiManager.NETWORK_STATE_CHANGED_ACTION you'll receive this twice because there are 2 methods in the NetworkInfo

isConnectedOrConnecting()

isConnected()

First time isConnectedOrConnecting() returns true and isConnected() false
Second time isConnectedOrConnecting() and isConnected() return true

Cheers

---

If you registered the activity as an intent listener then you will recieve the same message twice. Specifically, you need to choose whether you want to listen on the Package level (XML) or the programatic level.

If you set up a class for a broadcast reciever and attach the listen to it AND you attach an intent filter to the activity, then the message will be replicated twice.

I hope this solves your issue.

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