Develop Reference

detect if wifi connection offers internet access android studio

I'm currently working on an application that needs to know whether the phone has internet connection.
Using Connectivity Manager the app is able to generate an event when there is or there is no network connection. Problem is, I need to be connected to a WI-FI local hotspot for my app, and this WI-FI does not offer internet access. to summarise, ConnectivityManager tells me there is internet connection because i'm connected to this wi-fi, but this wi-fi does not offer a real connection.
Here is the code :
public void onReceive(Context context, Intent intent) {
if(intent == null || intent.getExtras() == null)
return;
ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = manager.getActiveNetworkInfo();
if(ni != null && ni.getState() == NetworkInfo.State.CONNECTED) {
connected = true;
} else if(intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY,Boolean.FALSE)) {
connected = false;
}
notifyStateToAll();
}
Is there a way to specify ConnectivityManager that one special Wi-Fi does not offer internet access?

Android: Checking network connectivity return not connected when connected to wifi/3g in Broadcast receiver

I want to check if device in connected or not in broadcastReceiver.
below is my code :
public boolean isOnline(Context context) {
NetworkInfo info = (NetworkInfo) ((ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();
if (info == null || !info.isConnected()) {
Log.e("UpdateDataReceiver","info: "+info);
return false;
}
return true;
}
Issue with my code:
above function returns me false (even when wifi connected) when BroadcastReceiver fires in background(when app is in background)
and it returns true when app is in foreground.
info: NetworkInfo: type: WIFI[], state: DISCONNECTED/BLOCKED, reason:
(unspecified), extra: (none), roaming: false, failover: false,
isAvailable: true, isConnectedToProvisioningNetwork: false, simId: 0
Device Info: Redmi Note

This is how I'm handling it as it turns out getActiveNetworkInfo will always return you DISCONNECTED/BLOCKED in a specific case even if there is network connection. This is the receive method in the BroadcastReceiver with intent filter ConnectivityManager.CONNECTIVITY_ACTION.
#Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager conn = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = conn.getActiveNetworkInfo();
NetworkInfo intentNetworkInfo = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if (intentNetworkInfo == null) {
intentNetworkInfo = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
}
if (networkInfo == null) {
networkInfo = intentNetworkInfo;
} else {
//when low battery get ActiveNetwork might receive DISCONNECTED/BLOCKED but the intent data is actually CONNECTED/CONNECTED
if (intentNetworkInfo != null && networkInfo.isConnectedOrConnecting() != intentNetworkInfo.isConnectedOrConnecting()) {
networkInfo = intentNetworkInfo;
}
}
//do something with networkInfo object
}
I've searched for better solution but no results. The case I've been able to reproduce 100% on my device (Pixel 7.1.2) is the following:
The device must be on low battery < 15% (other devices <20%)
Wifi is on, app is launched
Send app to background turnoff wifi and go to 3g (or vice versa)
Go back to the app
In that situation the app will report DISCONNECTED/BLOCKED from getActiveNetworkInfo.
If you change connectivity while in app it will be ok but if it is on background it wont. This won't happen while you are debugging because it will be charging the device even if the battery is low.
In the example above EXTRA_NETWORK_INFO in ConnectivityManager and WifiManager is actually same string "networkInfo" but I didn't wan't to risk it if in other Android versions they are different, so it is extra boilerplate.
You can directly use the networkInfo from the intent but I wanted to show here that there is a case where actualNetworkInfo is not the actual network info.

I believe the way you can do this is,
Register a Broadcast Receiver with an IntentFilter of ConnectivityManger.Connectivity_Action
private BroadcastReceiver receiverDataChange;
private void registerData(){
try {
receiverDataChange = new bcr_ToggleData();
IntentFilter filterData = new IntentFilter();
filterData.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(receiverDataChange, filterData);
} catch (IllegalArgumentException e) {
e.printStackTrace();
}}
Then in your Broadcast receiver class
public class bcr_ToggleData extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
int state = telephonyManager.getDataState();
switch (state){
case TelephonyManager.DATA_DISCONNECTED: // off
Log.d("DavidJ", "DISCONNECTED");
break;
case TelephonyManager.DATA_CONNECTED: // on
Log.d("DavidJ", "CONNECTED");
break;
}
}
}
}
This fires off when you go into your settings and turn on/off mobile data.
Hope this helps! :)

ConnectivityManager cm =
(ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
boolean isConnected = activeNetwork != null &&
activeNetwork.isConnectedOrConnecting();
I found this on this google tutorial: http://developer.android.com/intl/pt-br/training/monitoring-device-state/connectivity-monitoring.html. check it out.

Network checking functionality in android?

I use the following code to check the network availability while hitting remote service or accessing any web pages, for that i will call this below method every time before hitting web service, but i need any monitor which periodically monitor the web service at background and throw an alert network is not available, and if network is resume it net to throw an alert network is resumed , i don`t know how to achieve it.
public boolean isOnline(Context context)
{
boolean state=false;
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo wifiNetwork = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (wifiNetwork != null) {
state=wifiNetwork.isConnectedOrConnecting();
}
NetworkInfo mobileNetwork = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mobileNetwork != null) {
state=mobileNetwork.isConnectedOrConnecting();
}
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
if (activeNetwork != null) {
state=activeNetwork.isConnectedOrConnecting();
}
return state;
}

For that you need to implement the broadcast receiver, it will check the network connection in background and give alert when network has connectivity or not.
Please try below code.
1) Make one class which will extend brodcast receiver.
public class CheckInternetConnectionChangeReceiver extends BroadcastReceiver
{
public static boolean connectionStatus = false;
#Override
public void onReceive(Context context, Intent intent)
{
connectionStatus = CheckInternetConnection(context);
if(connectionStatus)
Toast.makeText(context, "Internet Connection Available", Toast.LENGTH_LONG).show();
else
Toast.makeText(context, "Internet Connection Not Available", Toast.LENGTH_LONG).show();
}
public boolean CheckInternetConnection(Context context)
{
ConnectivityManager connec = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
android.net.NetworkInfo wifi = connec.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
android.net.NetworkInfo mobile = connec.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (wifi.isConnected())
{
return true;
}
else if (!mobile.isConnected())
{
return false;
}
else if (mobile.isConnected())
{
return true;
}
return false;
}
}
// Here connectionStatus is a one boolean variable which stored the true or false value according to network . If it is available it will stored true value other wise it will stored false value.
Now Paste below code in your android manifest file.
<receiver android:name=".CheckInternetConnectionChangeReceiver">
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
</receiver>
Now when ever connection change it will call the brodcast receiver and store the appropriate value in the connnectionStatus variable.

Here is an effective way of checking for an active connection: http://yue-gao.blogspot.com/2010/12/android-effective-way-to-test-internet.html

CONNECTIVITY_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?

NOTE: For a recent, up-to-date answer, see this one below!
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

This is the proper way to register for connectivity changes on API 21 and higher. The following code can be placed in a base activity and that way you can expect every screen in your app (that inherits from this activity) to get these callbacks.
First, create a network callback which will monitor connectivity changes.
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
private val networkCallback: ConnectivityManager.NetworkCallback = object : ConnectivityManager.NetworkCallback() {
// Implement the callback methods that are relevant to the actions you want to take.
// I have implemented onAvailable for connecting and onLost for disconnecting.
override fun onAvailable(network: Network?) {
super.onAvailable(network)
}
override fun onLost(network: Network?) {
super.onLost(network)
}
}
Then, register and unregister this callback in the relevant spots.
override fun onResume() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
val cm = getSystemService(Context.CONNECTIVITY_SERVICE) as? ConnectivityManager
cm?.registerNetworkCallback(NetworkRequest.Builder().build(), networkCallback)
}
}
And unregister when appropriate.
override fun onPause() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
val cm = getSystemService(Context.CONNECTIVITY_SERVICE) as? ConnectivityManager
cm?.unregisterNetworkCallback(networkCallback)
}
}
Notice that there is a check for Build.VERSION_CODES.LOLLIPOP. This functionality is only available in Lollipop and above. Be sure to have a plan for how to handle network status changes in Pre-Lollipop devices if you support less than API 21 in your app.

Updated the code of Torsten, such that when WIFI gets disconnected, only the single appropriate broadcast is acted upon.
Used NetworkInfo.getDetailedState() == DetailedState.DISCONNECTED for the checking.
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.getDetailedState() == DetailedState.DISCONNECTED) {
// Wifi is disconnected
Log.d("Inetify","Wifi is disconnected: "+String.valueOf(networkInfo));
}
}
}

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.

I solved twice call by using SharedPref with Time.
private static final Long SYNCTIME = 800L;
private static final String LASTTIMESYNC = "DATE";
SharedPreferences sharedPreferences;
private static final String TAG = "Connection";
#Override
public void onReceive(Context context, Intent intent) {
Log.d(TAG, "Network connectivity change");
sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);
final ConnectivityManager connectivityManager = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
final NetworkInfo ni = connectivityManager.getActiveNetworkInfo();
if (ni != null && ni.isConnected()) {
if(System.currentTimeMillis()-sharedPreferences.getLong(LASTTIMESYNC, 0)>=SYNCTIME)
{
sharedPreferences.edit().putLong(LASTTIMESYNC, System.currentTimeMillis()).commit();
// Your code Here.
}
}
else if (intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, Boolean.FALSE)) {
Log.d(TAG, "There's no network connectivity");
}
}
Because there is small delay between 1.call and 2.call (About 200 milisec).
So in IF with time second call will stop and just first will continue.

I solved if with
in
onCreate()
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
intentFilter.addAction("android.net.wifi.WIFI_STATE_CHANGED");
intentFilter.addAction("android.net.wifi.STATE_CHANGE");
ctx.registerReceiver(outgoingReceiver, intentFilter);
in
BroadcastReceiver
public void onReceive(Context context, Intent intent) {
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 connected
Log.d("Inetify", "Wifi is connected: " + String.valueOf(networkInfo));
Log.e("intent action", intent.getAction());
if (isNetworkConnected(context)){
Log.e("WiFi", "is Connected. Saving...");
try {
saveFilesToServer("/" + ctx.getString(R.string.app_name).replaceAll(" ", "_") + "/Temp.txt");
} catch (IOException e) {
e.printStackTrace();
}
}
}
}}
boolean isNetworkConnected(Context context) {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = cm.getActiveNetworkInfo();
if (ni != null) {
Log.e("NetworkInfo", "!=null");
try{
//For 3G check
boolean is3g = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE)
.isConnectedOrConnecting();
//For WiFi Check
boolean isWifi = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI)
.isConnected();
Log.e("isWifi", "isWifi="+isWifi);
Log.e("is3g", "is3g="+is3g);
if (!isWifi)
{
return false;
}
else
{
return true;
}
}catch (Exception er){
return false;
}
} else{
Log.e("NetworkInfo", "==null");
return false;
}
}

I solved this problem by using the intent extra for NetworkInfo.
In the example below, onReceive event is fired only once if wifi is connected or mobile.
if (intent.getAction().equalsIgnoreCase(ConnectivityManager.CONNECTIVITY_ACTION)) {
NetworkInfo networkInfo = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
boolean screenIsOn = false;
// Prüfen ob Screen on ist
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
screenIsOn = pm.isInteractive();
} else {
screenIsOn = pm.isScreenOn();
}
if (Helper.isNetworkConnected(context)) {
if (networkInfo.isConnected() && networkInfo.isAvailable()) {
Log.v(logTAG + "onReceive", "connected");
if (networkInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
Log.v(logTAG + "onReceive", "mobile connected");
} else if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {
Log.v(logTAG + "onReceive", "wifi connected");
}
}
}
and my helper:
public static boolean isNetworkConnected(Context ctx) {
ConnectivityManager cm = (ConnectivityManager) ctx.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = cm.getActiveNetworkInfo();
return ni != null;
}

If you only want to receive it once, you can simply control it through variables.
if (ConnectivityManager.CONNECTIVITY_ACTION.equals(intent.getAction())) {
NetworkInfo activeNetwork = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if (activeNetwork != null) { // connected to the internet
if (activeNetwork.isConnected() && !isUpdated) {
if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
// connected to wifi
} else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
// connected to the mobile provider's data plan
}
isUpdated = true;
} else {
isUpdated = false;
}
}
}

When turning WIFI ON,
With MOBILE data ON, two broadcasts are sent:
Broadcast #1 : MOBILE data disconnected, and
Broadcast #2 : WIFI connected
With MOBILE data OFF, only one broadcast is sent:
Broadcast #1 : WIFI connected
Similar behavior can be observed while turning the WIFI OFF under the above two conditions.
To distinguish between the two, please follow #2 and #3 below:
#Override
public void onReceive(Context context, Intent intent) {
Log.d(TAG, "*** Action: " + intent.getParcelableExtra("networkInfo"));
NetworkInfo netInfo = intent.getParcelableExtra("networkInfo");
if(intent.getAction().equalsIgnoreCase("android.net.conn.CONNECTIVITY_CHANGE")) {
ConnectivityManager connectivityManager
= (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();
if (activeNetInfo != null) {
if (netInfo.getType() == ConnectivityManager.TYPE_WIFI) {
if (netInfo.getState().name().contains("DISCONNECTED")
&& activeNetInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
Log.d(TAG, "WIFI disconnect created this broadcast. MOBILE data ON."); // #1
} else if (netInfo.getState().name().contains("CONNECTED")
&& activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) {
Log.d(TAG, "WIFI connect created this broadcast."); // #2
}
} else if (netInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
if (netInfo.getState().name().contains("DISCONNECTED")
&& activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) {
Log.d(TAG, "MOBILE data disconnect created this broadcast. WIFI ON."); // #3
} else if (netInfo.getState().name().contains("CONNECTED")
&& activeNetInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
Log.d(TAG, "MOBILE data connect created this broadcast."); // #4
}
}
} else {
Log.d(TAG, "No network available");
}
}
}

The way I handled it, was simply by saving the state of the network and then comparing it to see if there was a change.
public class ConnectivityChangedReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
boolean previouslyConnected = MyApp.getInstance().isNetworkPreviouslyConnected();
boolean currentlyConnected = MyApp.getInstance().isNetworkConnected();
if (previouslyConnected != currentlyConnected) {
// do something and reset
MyApp.getInstance().resetNetworkPreviouslyConnected();
}
}
}
If this is the approach you take, it's important to reset it in onResume of your fragment or activity, so that it holds the current value:
#Override
public void onResume() {
super.onResume();
MyApp.getInstance().resetNetworkPreviouslyConnected();
}
I did that in my BaseFragment, a parent of all fragments in my app.

check networkType from intent
and compare activeNetworkInfo.getType()
Bundle bundle = intent.getExtras();
ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = manager.getActiveNetworkInfo();
if(ni != null && ni.getState() == NetworkInfo.State.CONNECTED) {
if(bundle.getInt("networkType") == ni.getType()) {
// active network intent
}
}

Found a special case for network connectivity saying there is no internet but actually there is. It turns out getActiveNetworkInfo will always return you DISCONNECTED/BLOCKED in a specific case when network is changed while battery level is low and app was just switched
Check out this post

Only listen to action "android.net.conn.CONNECTIVITY_CHANGE". It's broadcasted whenever connection is established or destroyed.
"android.net.wifi.STATE_CHANGE" will be broadcasted when connection established. So you get two triggers.
Enjoy!

ANDROID: if WiFi is enabled AND active, launch an intent

This is what I would like to do :
=> IF WiFi is enabled AND active, launch an intent (in fact it's a WebView that gets its content=>the instructions of my app on the web)
=> IF NOT, then I would launch another intent so that I don't show a WebView with "Web page not available ... The Web page at http://www.mywebsite.com might be temporarily down or it may have moved ..."
I tought initially to use
if(wifi.isWifiEnabled())
but that does not say if the Wifi connection is ACTIVE or not. It says only that the user has turned the switch on. The device may or may not be connected... Is this correct ?
Then I tried to use :
if (wifi.getConnectionInfo().getSSID()!= null)
but I noticed that it returns a string even if the connection has been lost or has been disabled ... ?
How should I do then ?
wifi = (WifiManager)getSystemService(Context.WIFI_SERVICE);
Intent intent_instructions;
if (wifi.getConnectionInfo().getSSID()!= null){
Log.i("Hub", "WiFi is enabled AND active !");
Log.i("Hub", "SSID = "+wifi.getConnectionInfo().getSSID());
intent_instructions = new Intent(this, Instructions.class);
}else{
Log.i("Hub", "NO WiFi");
intent_instructions = new Intent(this, Instructions_No_WiFi.class);
}
this.startActivity(intent_instructions);
Is there a more general way to test if the device has the connectivity to the internet just before launching an intent ? be it through Wifi, 3G, etc ...
Thanks in advance for your help.

You can use the following code to check for connectivity:
private static boolean isConnected(Context context) {
ConnectivityManager connectivityManager = (ConnectivityManager)
context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = null;
if (connectivityManager != null) {
networkInfo =
connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
}
return networkInfo == null ? false : networkInfo.isConnected();
}
Please make sure that you've registered the android.net.conn.CONNECTIVITY_CHANGE intent in your Manifest, or else, you'll never receive a notification that you're online.
I've been struggling with this issue for the last couple of days and I just now realized that I needed to register CONNECTIVITY_CHANGE and not only WIFI_STATE_CHANGED.

Try android.net.ConnectivityManager.getActiveNetworkInfo(): if it returns null you have no connection; if it returns a NetworkInfo object, you can check the connection's state with NetworkInfo.getState(), and if it's NetworkInfo.State.CONNECTED then you're connected, else you're not.

You can do it as follows:
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if(WifiManager.WIFI_STATE_CHANGED_ACTION.equals(action)){
Log.d("WIFI", "WIFI has changed");
int wifiState = intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, -1);
Log.d("WIFI", "WIFI State = " + wifiState);
setCurrentWifiState(wifiState);
}
You will get 0,1,2,3 depending on which state the Wifi is in, so for example 2 is connecting, you can check the rest in the documents

In your BroadcastReceiver class:
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION)){
boolean connected = intent.getBooleanExtra(WifiManager.EXTRA_SUPPLICANT_CONNECTED, false);
if (connected){
// start your service here
}
}
}
And in your AndroidManifest.xml make sure you register for the android.net.wifi.supplicant.CONNECTION_CHANGE broadcast intent.
<intent-filter >
<action android:name="android.net.wifi.supplicant.CONNECTION_CHANGE" />
</intent-filter>

isConnected() doesnt work fully ok, research something else
final ConnectivityManager connMgr = (ConnectivityManager)
this.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() && wifi.getDetailedState() == DetailedState.CONNECTED){
Toast.makeText(this, "Wifi" , Toast.LENGTH_LONG).show();
}
else if( mobile.isAvailable() && mobile.getDetailedState() == DetailedState.CONNECTED ){
Toast.makeText(this, "Mobile 3G " , Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(this, "No Network " , Toast.LENGTH_LONG).show();
}
this code check if you are with wifi or 3g or nothing , in the case of wifi on but not connected to a net or 3g have signal problem it detect this details, with DetailedStates