QB API with my mobile application.

Hi all,

I want to integrate QB API with my mobile application. While I am doing I got struck in authentication
$OAuth2LoginHelper = $dataService->getOAuth2LoginHelper();
I did till the above code. After that I am not able to do any thing. I want to get "AuthorizationCodeURL".

I have only APIs so I cant run header("Location: ".$authorizationUrl); to connect to QB.

I am struck for several days. Please help me to get access token to get authorized.

Regards