Problem implementing Leaderboard button

Questions & Answers
1

Hello. I want to add a leaderboard to my android game. I’ve created one in google play console successfully. I’ve used three scripts for managing score, leaderbooards and game/player:

  1. LeaderBoardManagerScript where I manage everything related to leaderboards (login, add score and show leaderboard.

  2. ScoreScript, where I manage everything related to score system

  3. Player script, where I manage player and game behavior.

    using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;
    using GooglePlayGames;
    using UnityEngine.SocialPlatforms;
    using UnityEngine.UI;

    public class LeaderboardManagerScript : MonoBehaviour
    {
    public int score;
    public static LeaderboardManagerScript current;

    private void Awake()
{
    if (current == null)
        current = this;
}

// Start is called before the first frame update
void Start()
{
    PlayGamesPlatform.Activate();
    Login();
}

// Update is called once per frame
void Update()
{ 
    
}

public void Login()
{
    Social.localUser.Authenticate((bool success) => 
    { 
    });
}

public void AddScore()
{
    Social.ReportScore(ScoreScript.current.score, Leaderboard.leaderboard_best_scores, (bool success) =>
    {
    });
}

public void ShowLeaderboard()
{
    if (Social.localUser.authenticated)
    {
        PlayGamesPlatform.Instance.ShowLeaderboardUI(Leaderboard.leaderboard_best_scores);
    }
    else
    {
        Login();
    }
}

    }

    using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;
    using UnityEngine.UI;

    public class ScoreScript : MonoBehaviour
    {
    public int score;
    public Text scoreText;
    public Text highScoreText;

    public static ScoreScript current;

private void Awake()
{
    if (current == null)
        current = this;
}

void Start()
{
    score = 0;
}

void Update()
{
    scoreText.text = score.ToString();
}

private void OnTriggerEnter(Collider other)
{
    if (other.gameObject.tag == "Score")
    {
        score++;
            PlayerScript.current.playerSpeed = PlayerScript.current.playerSpeed + 3;
    }
        

    if (other.gameObject.tag == "Score2")
    {
        score += 2;
            PlayerScript.current.playerSpeed = PlayerScript.current.playerSpeed + 3;
    }

    if (other.gameObject.tag == "Jackpot") 
    { 
        score += 5;
            PlayerScript.current.playerSpeed = PlayerScript.current.playerSpeed + 5;
    }
}  

public void CheckHighScore()
{
    if (PlayerPrefs.HasKey("highScore"))
    {
        if (score > PlayerPrefs.GetInt("highScore"))
            PlayerPrefs.SetInt("highScore", score); 
    }
    else
        PlayerPrefs.SetInt("highScore", score); 

    highScoreText.text = PlayerPrefs.GetInt("highScore").ToString(); 
}

    }

I’ve created a button in canvas for leaderboard, set the onclick event to playerScript where I put the following void

    public void ShowLeaderboard()
    {
        LeaderboardManagerScript.current.ShowLeaderboard();
    }

when I run the game, if I push the Leaderboard button, I get a null reference exception. Not sure why, so I’m asking help…

2

@PaoloG79

The problem might be how you get the reference for the leaderboardmanagerscript object. I’m guessing that you either never get a reference of said script attached to a game object or at some point when you are getting it that it is set to null. You should show how you get said reference if you get it at all. If you never get the reference then check where the script is attached and get that reference. Best of luck.