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Game Development

Sean May
Sean May
9,145 Points

Player Movement, Enemy Movement, follow camera not disabled before pressing space

I've been working through the tutorials, and everything has worked thus far, but, now that I've written everything for the GameState script, the player movement and enemy movement as well as the follow camera aren't being disabled upon launch before I press the space button. Here's my code:

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.SceneManagement;


public class GameState : MonoBehaviour {

    private bool gameStarted = false;

    [SerializeField]
    private Text gameStateText;

    [SerializeField]
    private GameObject player;

    [SerializeField]
    private BirdMovement birdMovement;

    [SerializeField]
    private FollowCamera followCamera;

    private float restartDelay = 3f;
    private float restartTimer;
    private PlayerMovement playerMovement;
    private PlayerHealth playerHealth;

    // Use this for initialization
    void Start () {
        Cursor.visible = false;

        playerMovement = playerMovement.GetComponent<PlayerMovement>();
        playerHealth = playerHealth.GetComponent<PlayerHealth>();

        //prevent player, bird from moving at beginning
        playerMovement.enabled = false;
        birdMovement.enabled = false;

        //prevent follow camera from moving
        followCamera.enabled = false;

    }


    private void StartGame() {
        //set game state
        gameStarted = true;
        //remove start text
        gameStateText.color = Color.clear;

        //enable player, bird movement
        playerMovement.enabled = true;
        birdMovement.enabled = true;

        //enable camera movement
        followCamera.enabled = true;

    }

    private void EndGame() {
        //set game state
        gameStarted = false;

        //re-enable text, change to 'game over'
        gameStateText.color = Color.white;
        gameStateText.text = "Game Over";

        //remove player from game
        player.SetActive (false);
    }

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

        //if game is not started, and player presses spacebar, then...

        //Input is a built-in class

        if(gameStarted == false && Input.GetKeyUp(KeyCode.Space)) {
            //start the game
            StartGame();
        }

        //if player is no longer alive...
        if(playerHealth.playerAlive == false) {
            //...end the game
            EndGame();

            //after game ends, start timer to count to restart
            restartTimer = restartTimer + Time.deltaTime;

            if(restartTimer > restartDelay){
                //reload the current level
                SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex); 
            }
        }
    }
}

Sometimes when I run the debugger I get the following error

NullReferenceException: Object reference not set to an instance of an object

on the

playerMovement = playerMovement.GetComponent<PlayerMovement>();

line. It's so upsetting to get this error after going through so much going right :D, so any help would be very much appreciated.

Sean May
Sean May
9,145 Points

Figured this out with some digging!

the playerMovement = playerMovement.GetComponent<PlayerMovement>();

should be

playerMovement = player.GetComponent<PlayerMovement>();