i cant solve this some one help me

Unity Engine
1

hello im new in the scripting thing but i was hoping u can help me i build a ui system that keep track of the health and the items that the player has right now but i allways get the error
and the ui is not changing to the health or the items what to do?:

NullReferenceException: Object reference not set to an instance of an object
UI.Start () (at Assets/UI.cs:17)

oh and u can download the codes below if u want

this is the code:

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

public class UI : MonoBehaviour
{
public Text Life;
public Text Bullets;

private PlayerManager player;
private float health;
private int item;

public void Start()
{
health = player.health;
item = player.itemCount;
}

// Update is called once per frame
private void Update()
{
Life.text = health.ToString();
Bullets.text = $“{item.ToString()}/3”;
}
}

this is the playmanager code:

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

public class PlayerManager : MonoBehaviour
{
public int id;
public string username;
public float health;
public float maxHealth;
public int itemCount = 0;
public MeshRenderer model;

public void Initialized(int _id, string _username)
{
id = _id;
username = _username;
health = maxHealth;
}

public void SetHealth(float _health)
{
health = _health;

if (health <= 0f)
{
Die();
}
}

public void Die()
{
model.enabled = false;
}

public void Respawn()
{
model.enabled = true;
SetHealth(maxHealth);
}
}

6890231–805724–UI.cs (564 Bytes)
6890231–805727–PlayerManager.cs (810 Bytes)

2

First, use code tags, they provide better formatting and line numbers. Second, null errors as easy to fix. Something doesn’t have a value. So you can go to the line it references (line 17 in your errors case) and figure out what is null. I’m not going to count the lines, but at a glance, my guess is since you have a private PlayerManager variable, chances are when you try to get health and itemCount from it, the variable player is null.

So you have to assign a value to player. Simple approach is just make the variable Public and drag and drop in the inspector.

3

i need to make player public ?

4

oh an btw this is line 17 : health = player.health;
but i get the same in line 18 to:item = player.itemCount

5

As I said, the simple approach is to make player public and drag and drop your PlayerManager gameObject into the slot, just like you hopefully did with your two Text objects.

6

Of course you will, because player is null. Null errors are the simplest to solve, and fairly common, so get use to seeing them and learning how to solve them.

7

TNX its work but i got new problem now the ui isnt showing the numbers its need its stuck on zero and i dont get any errors

8

never mind now i fixed it all tnx anyway