Android: Check if the device has internet access on devices with API level >= 23.

ConnectivityChecker.kt

package me.a_hoffmann.gists

import android.content.Context
import android.net.ConnectivityManager
import android.net.NetworkCapabilities

/**
 * Checks if the device has an internet connection.
 * NOTE: Works only on android API level 23 and above!
 */
class ConnectivityChecker(private val context: Context){

    /**
     * Check if the device has an internet connection.
     *
     * @return True if the device is connected to a network which also gives it access to the internet.
     * False otherwise.
     */
    fun isInternetAvailable(): Boolean {
        val connectivityManager = context.getSystemService(
                Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
                ?: return false

        val activeNetwork = connectivityManager.activeNetwork ?: return false
        val capabilities = connectivityManager.getNetworkCapabilities(activeNetwork) ?: return false

        // If we check only for "NET_CAPABILITY_INTERNET", we get "true" if we are connected to a wifi
        // which has no access to the internet. "NET_CAPABILITY_VALIDATED" also verifies that we
        // are online
        return capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
                && capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)
    }
}