Check Network Connectivity

To check network connectivity, we can use ConnectivityManager to get info of active network.

package com.exercise.AndroidNetworkConnectivity;

import android.app.Activity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.widget.Toast;

public class AndroidNetworkConnectivityActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        
        ConnectivityManager connectivityManager 
        = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
        
        if (activeNetworkInfo == null){
         Toast.makeText(AndroidNetworkConnectivityActivity.this, 
           "No Active Network", 
           Toast.LENGTH_LONG).show();
        }else{
         if (activeNetworkInfo.isConnected()){
             Toast.makeText(AndroidNetworkConnectivityActivity.this, 
               "network is Connected", 
               Toast.LENGTH_LONG).show();
            }else if (activeNetworkInfo.isConnectedOrConnecting()){
             Toast.makeText(AndroidNetworkConnectivityActivity.this, 
               "network is Connecting", 
               Toast.LENGTH_LONG).show();
            }
        }
    }
}

Remark: uses permission of "android.permission.ACCESS_NETWORK_STATE" is needed.