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Instantiated gameObject's self-written component is not working

I'm trying to implement chest mechanic in my game. When a user touches to chest, chest disappears and heart shows up. When player touches the instantiated heart, it must disappear and add 1 to life value, but the script is not working.
Chest.cs:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Chest : MonoBehaviour
{
public GameObject heart;
public GameObject _heart; //Instantiated heart.
void OnTriggerEnter2D(Collider2D col){
if (col.gameObject.tag == "Player"){
Vector3 insPos = transform.position;
_heart = Instantiate(heart,new Vector3(insPos.x,insPos.y+0.5f,insPos.z),Quaternion.identity);
_heart.AddComponent<Heart>();
_heart.GetComponent<Heart>().ls = GameObject.FindGameObjectWithTag("Player").GetComponent<LifeSystem>();
Destroy(gameObject);
}
}
}
Heart.cs:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Heart : MonoBehaviour
{
public LifeSystem ls;
void OnTriggerEnter2D(Collider2D col){
if (col.gameObject.tag == "Player"){
SoundManager.PlaySound("CollectCoinSound");
ls.lifes += 1;
Destroy(gameObject);
}
}
}
I check the components of the instantiated heart when player touches the chest and I can see that life system reference is added and so heart script is.
Thanks for your time.

You need to meet these conditions in order for OnTriggerEnter2D to be called on the spawned Hearth:
At least one between Player and Hearth need to have a Rigidbody2D component
Both Player and Hearth need to have a collider with IsTrigger = true
Player and Hearth GameObjects need to be on two interacting layers in the collision matrix
The Hearth component needs to be either on the same GameObject with a collider or on the same GameObject with the RigidBody2D
I actually simplified rules 1 and 2 a bit to show the most common use-case: if you want to know the actual rules for collisions, you can find them here (see the matrix at the bottom).

Besides the general collision rules I would make sure your fields have the correct type in the first place and already attach the Heart component to your prefab.
Also there is no need for find .. You already know the reference to the player you are colliding with
public class Chest : MonoBehaviour
{
public Heart heartPrefab;
void OnTriggerEnter2D(Collider2D col)
{
if (col.CompareTag("Player"))
{
Instantiate(heart, transform.position + Vector3.up * 0.5f), Quaternion.identity);
Destroy(gameObject);
}
}
}
and then simply do
public class Heart : MonoBehaviour
{
private void OnTriggerEnter2D(Collider2D col)
{
if (col.TryGetComponent<LifeSystem>(out var ls))
{
SoundManager.PlaySound("CollectCoinSound");
ls.lifes += 1;
Destroy(gameObject);
}
}
}
and rather have the LifeSystem attached to your player object.
In general I would kind of expect both eventually triggered at the same time since the heart might be already triggered if spawning right where the player is

This message parameter has to be of type: Collision

I have done this in 3D.
I don't have "is trigger" chosen in any objects.
I wanted to write down "it works" when my object hit an object that is tagged "Obstacle". I need help.
using UnityEngine;
public class Collision : MonoBehaviour
{
void OnCollisionEnter(Collision collision)
{
if (collision.gameObject.tag == "Obstacle")
{
Debug.Log("it works");
}
}
}
(I'm new to Unity so please try to explain as I could understand TYSM.)

You should add the Rigidbody component to the object. It is necessary for collision detection

OnCollisonEnter2D Unity c# script for 2D collisions not working

I am trying to make a 2d platformer. I have an object that when the player collides with it, the game restarts. For some reason it doesn't work. I set a simple Debug.Log statement to test it. But, it just doesn't work. Here's the code
using UnityEngine;
public class Collision : MonoBehaviour
{
private void OnCollisionEnter2D(Collision2D collisionInfo)
if (collisionInfo.collider.tag == "Lose")
{
Debug.Log("lose");
}
}
}

Can't figure out what i've done wrong

I'm new to programming and I'm currently trying to do a simple game in Unity.
The code makes some things dissapear when they touch the ground and it works well but the "Evaporated" variable does not update in the Unity Inspector. When something touch the ground, evaporated should be incremented, but it stays at 0.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.Threading;
public class EnemyEvaporate : MonoBehaviour
{
public GameObject Enemy;
public int Evaporated;
void OnCollisionEnter(Collision CollisionInfo)
{
if (CollisionInfo.gameObject.name == "Map" || CollisionInfo.gameObject.name == "Player")
{
Thread.Sleep(15);
gameObject.SetActive(false);
Evaporated++;
}
}
}

I'm not really sure what's the behavior you're trying to get in this script. If Evaporated is some kind of 'Global counter' for score, it need to be written different and not store inside script for this gameObject.
It might be related to your gameObject.SetActive(false) which will deactivate your object, so in fact it will disables also the scripts connected with it (and especially this one. SetActive documentation) and removes them from Update() for a given gameObject (so given enemy. If you have 4 Enemy objects on the Scene, in fact you have 4 instances of this script and each has own Evaporated variable)

Why won't you move the void OnCollisionEnter(Collision CollisionInfo) to your Enemy scipt? I think Enemy should now if it collided with anything, not some external script.
You can also use tags instead of names when detecting Collisions.
Also, gameObject.SetActive(false) - if you set your gameObject to disabled, nothing more from its script will happen unless you set it to active again. It e.g. cancels all Coroutine. The gameObject is just "sleeping", I would say. It's not destroyed - you still can see it in your Hierarchy window - but it can't do anything. (By the way, in this case you're setting EnemyEvaporate gameObject as disabled, not Enemy gameObject.)
Also, you can use Coroutine instead of Thread.Sleep(15). It is more common to use Coroutines than Threads in Unity.
Now, Evaporation. If you want to count how many Enemies evaporated (I suppose, looking at Evaporated++;) you should have some external object to count it. The simplest way I can propose fow now is creating a GameObject with EvaporationCounter : MonoBehaviour script attached to it. You can also use Singleton pattern to be sure there's only one object of this type.
public class EvaporationCounter : MonoBehaviour
{
private int evaporates;
public int Evaporates {
get { return evaporates; }
private set
{
if (value >= 0) evaporates = value;
}
}
public void AddEvaporation()
{
Evaporates++;
}
}
Your Enemy class could look like:
public class Enemy : MonoBehaviour
{
private IEnumerator coroutine;
private EvaporationCounter evaporationCounter;
private void Start()
{
evaporationCounter = FindObjectOfType<EvaporationCounter>();
}
private IEnumerator WaitAndSetInactive(float waitTime)
{
yield return new WaitForSeconds(waitTime);
gameObject.SetActive(false);
}
private void OnCollisionEnter(Collision CollisionInfo)
{
if (!CollisionInfo.gameObject.CompareTag("Map") && !CollisionInfo.gameObject.CompareTag("Player")) return;
if (evaporationCounter != null)
evaporationCounter.AddEvaporation();
StartCoroutine(WaitAndSetInactive(15f));
}
}
Calling evaporationCounter.AddEvaporation() from the Enemy script is not the best solution, since it does not apply to the Dependency Inversion principle but I would say it's good for the beginning with Unity.

Calling a script from NPCs in Unity to trigger dialogue

I have followed Brackeys tutorial on Youtube (https://www.youtube.com/watch?v=_nRzoTzeyxU) on how to create a dialogue system for a game. I am currently attempting to adapt this system to where the player can walk up to an NPC and press the "Submit" button to access their dialogue, instead of clicking a button on the canvas/UI like the video shows. To those who have played games like Super Mario64, The Legend of Zelda: Ocarina of time, or most games with text dialogue you may recognize this.
The Interactable script I created detects whether the player is within the collision sphere or not that the NPC has, and allows the player to press the "Submit" button on what is supposed to call the dialogue for the NPC in range. I'm just not sure how to call the script that I named DialogueTrigger that holds the dialogue for the NPC. That, or what I'm trying to accomplish is not being accomplished in the way that I am trying. Any help would be appreciated.
Interactable Script: `
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Interactable : MonoBehaviour {
private GameObject triggeringNpc;
private bool triggering;
public DialogueTrigger Diag;
void Start()
{
}
void Update()
{
if(triggering)
{
Debug.Log("Within Range");
if (Input.GetButtonDown("Submit"))
{
Debug.Log("Pressed the Interact Button");
Diag.TriggerDialogue();
}
}
}
void OnTriggerEnter(Collider other)
{
if(other.tag == "NPC")
{
triggering = true;
triggeringNpc = other.gameObject;
}
}
void OnTriggerExit(Collider other)
{
if(other.tag == "NPC")
{
triggering = false;
triggeringNpc = null;
}
}
}
`
Right now I can put a script for one NPC in the script and it works, but I would rather it call whatever Dialogue Trigger Script that the NPC has. I'm sure there's something I'm missing here.
This one is for Dialogue Trigger
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DialogueTrigger : MonoBehaviour
{
public Dialogue dialogue;
public void TriggerDialogue ()
{
FindObjectOfType<DialogueManager>().StartDialogue(dialogue);
Debug.Log("dm called"); } else { Debug.Log("dm is null"); }
}
}

Solved this as soon as I posted it. Turns out I just needed to combine the Interactable script with the dialogue triggers script and rearranging the collision tags to hit the player that was tagged "Player" rather than having a separate script that detected collision to the NPC.