How to run project continuously after back from setting dialog

I am using gps alertdialog for checking gps status.when i turn on gps and press back button to come on my app where it was leave.Then activity is not responsive means not running .How is it possible to run project continuously on pressing back button after gps on.

My code is..

 private void loginProcess() {
    if (!gpsTracker.canGetLocation()){
        gpsTracker.showSettingsAlert();
    }
    else
    {
        doLogin();
    }
}

private void doLogin() {

    new Handler().postDelayed(new Runnable() {
        @Override
        public void run() {

            if (checkConnectivity.isNetworkAvailable()) {
                    if (!SharedPreferencesUtility.loadUsername(context).equalsIgnoreCase("0")
                            || !SharedPreferencesUtility.loadPassword(context).equalsIgnoreCase("0")
                            || sharedPreferencesUtility.getLoginflag(context)) {
                        startActivity(new Intent(context, MainActivity.class)
                                .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP).putExtra(
                                        "issplash", true));
                        finish();
                    } else {
                        startActivity(new Intent(context, LoginActivity.class)
                                .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP).putExtra(
                                        "issplash", true));
                        finish();
                    }
            }
            else
                Toast.makeText(context, R.string.internetdisabledmessage, Toast.LENGTH_LONG).show();
            splashProgressBar.setVisibility(View.INVISIBLE);
        }
    }, IWebConstant.SPLASH_TIMEOUT);
}