Adding Check for Network

LoginActivity.kt

class LoginActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        ...
        signInButton.setOnClickListener { view ->
            if (isNetworkConnected()) {
                startActivity(Intent(this@LoginActivity, MainActivity::class.java))
            } else {
                AlertDialog.Builder(this).setTitle("No Internet Connection")
                    .setMessage("Please check your internet connection and try again")
                    .setPositiveButton(android.R.string.ok) { _, _ -> }
                    .setIcon(android.R.drawable.ic_dialog_alert).show()
            }
        }
    }
}