android studio How to continuously check if there is an active internet connection

Question

I've already read many other answers posted on the internet but they are not exactly what I'm looking for, I know how to check if the device is connected/disconnected to the internet/mobile data what I am trying to do is check if data is transferable through that network or not, you might be connected to a network but might not be able to transfer data through that network.

here is what I'm doing now

 val listener = object : ConnectivityManager.NetworkCallback() {
        override fun onAvailable(network: Network) {
            super.onAvailable(network)
            isActiveNetwork()
        }

        override fun onUnavailable() {
            super.onUnavailable()
       }

        override fun onLost(network: Network) {
            super.onLost(network)
            // no internet
         }
    }

(getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager).registerNetworkCallback(NetworkRequest.Builder().build(), listener )

the isActiveNetwork method is used to check if the internet connection is active or not

private fun isActiveNetwork(){
    try {
        if(InetAddress.getByName("www.google.com").isReachable(5000)){
             //active
        }            
        else{
            // not active
        } 
    } catch (e: Exception) {
        //not active
    }
}

the problem is this method will check if the internet connection is active once and that's all, I've tried to do this

private fun isActiveNetwork(){
    try {
        if(InetAddress.getByName("www.google.com").isReachable(5000)){
             //active
        }            
        else{
            isActiveNetwork()
        } 
    } catch (e: Exception) {
        isActiveNetwork()
    }
}

to try and keep checking every 5 seconds to see if the internet connection is active, but that caused my app to crash because of StackOverflow.... any suggestions?

Please have a look at [this](https://stackoverflow.com/questions/32547006/connectivitymanager-getnetworkinfoint-deprecated/54641263#54641263) answer, it's in java but will give some clue — Zain, Jun 05 '20 at 16:54

score 1 · Accepted Answer · edited Jun 06 '20 at 05:11

1

You can use Runnable and post it using handler to continuously check internet connection every 5 second. Declare a global boolean variable isConnected and create a Runnable like:

private var isActiveNetwork= object : Runnable {
        override fun run() {
            try {
                if(InetAddress.getByName("www.google.com").isReachable(5000)) 
                 {
                  isConnected = true
                 }            
               else{
                  isConnected = false
                 }
               Handler().postDelayed(this,5000) 
              } 
          catch (e: Exception) {
              isConnected = false
         }

        }
    }

Now you can start this Runnable from network request callback:

 override fun onAvailable(network: Network) {
            super.onAvailable(network)
            Handler().post(isActiveNetwork)
        }

edited Jun 06 '20 at 05:11

MoTahir

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answered Jun 05 '20 at 16:38

Alpha 1

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this kind of works but you need to run it on background thread not main thread – MoTahir Jun 05 '20 at 18:08
@MoTahir won't main thread blocked when checked continuously without delaying? – Animesh Sahu Jun 06 '20 at 02:49
1

If you apply the code above inside an activity, it won't be affected somehow, I actually got the main thread error when I was using the main looper (in the activity), but if you make a separate file for the network Listener then use, you need to use the main looper – MoTahir Jun 07 '20 at 11:27

android studio How to continuously check if there is an active internet connection

1 Answers1