Using FB sdk in unity to get Information, share, get and set score

FBUnityHandler

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using Facebook.Unity;
using System.Collections.Generic;
using Facebook.MiniJSON;

public class FBController : MonoBehaviour {

	Button[] btn = new Button[4];
	Image avatar;
	Text txt_username;
	// Use this for initialization
	void Awake () {
		Transform group = transform.FindChild ("ButtonGroup");
		avatar = transform.FindChild ("Img_Avatar").GetComponent<Image> ();
		txt_username = transform.FindChild ("Txt_Username").GetComponent<Text> ();
		int i = 0;
		foreach (Transform item in group) {
			btn [i++] = item.GetComponent<Button> ();
			Debug.Log (""+btn[i-1]);
		}
		InitFB ();
	}
	
	void Start ()
	{
		btn[0].onClick.AddListener (()=>InitFB());
		btn[1].onClick.AddListener (()=>LoginFB());
		btn [2].onClick.AddListener (() => ShareWithFriend ());
		btn [3].onClick.AddListener (() => QueryScores ());

	}

	void OnGUI ()
	{
	    
	}

	void InitFB ()
	{
		FB.Init (OnInitComplete, OnHideUnity);
	}

	void LoginFB ()
	{
		FB.LogInWithReadPermissions(new List<string>() { "public_profile", "email", "user_friends" }, this.HandleResult);
	}

	private void CallFBLoginForPublish()
	{
		FB.LogInWithPublishPermissions(new List<string>() { "publish_actions" }, this.HandleResult);
	}



	void HandleResult (ILoginResult result)
	{
		if (result == null)
		{
			Debug.Log ("RESULT NULL");
			return;
		}

		// Some platforms return the empty string instead of null.
		if (!string.IsNullOrEmpty(result.Error))
		{

			Debug.Log ("Error " +result.Error);
		}
		else if (result.Cancelled)
		{
			Debug.Log ("Cancelled Response: " +result.RawResult);
		}
		else if (!string.IsNullOrEmpty(result.RawResult))
		{
			Debug.Log ("Success Response: " +result.RawResult);
			DealWithCallBack ();
		}
		else
		{
			Debug.Log ("Empty Response");
		}
	}

	void DealWithCallBack ()
	{
		if (FB.IsLoggedIn) {
			FB.API ("/me/picture?type=square&height=128&width=128", HttpMethod.GET, GetPicture);
			FB.API ("/me/?fields=id,first_name", HttpMethod.GET, GetUsername);
		}
	}

	void GetPicture (IGraphResult result)
	{
		if (result.Error == null) {
			avatar.sprite = Sprite.Create (result.Texture, new Rect (0, 0, 128, 128), new Vector2 ());
		}
	}

	void GetUsername (IGraphResult result)
	{
		if (result.Error != null) {
			FB.API ("/me/?fields=id,first_name", HttpMethod.GET, GetUsername);
			return;
		}
		var objs = Json.Deserialize (result.RawResult) as Dictionary<string, object>;
		txt_username.text = "Hello, "+objs["first_name"];
	}

	private void OnInitComplete()
	{
		string logMessage = string.Format(
			"OnInitCompleteCalled IsLoggedIn='{0}' IsInitialized='{1}'",
			FB.IsLoggedIn,
			FB.IsInitialized);
		Debug.Log (logMessage);
	}

	private void OnHideUnity(bool isGameShown)
	{
		string logMessage = string.Format("Success Response: OnHideUnity Called {0}\n", isGameShown);
		Debug.Log (logMessage);
	}

	public void ShareWithFriend(){
		FB.FeedShare ("", null, "Name", "CAP", "DES", null, "", null);
	}
		
	// All Scores API related Things

	public void QueryScores()
	{
		FB.API ("/app/scores?fields=score,user.limit(30)", HttpMethod.GET, ScoresCallback);
	}

	private void ScoresCallback(IResult result)
	{
		Debug.Log ("Scores callback: " + result.RawResult);
	}

	public void SetScore()
	{
		var scoreData = new Dictionary<string,string> ();
		scoreData ["score"] = Random.Range (10, 200).ToString ();
		FB.API ("/me/scores", HttpMethod.POST, delegate(IGraphResult result) {
			Debug.Log ("Score submit result: " + result.RawResult);
		}, scoreData);
	}
}