character-system/Runtime/UI/HealthBarUi.cs

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

namespace KairoEngine.CharacterSystem
{
    public class HealthBarUi : MonoBehaviour
    {
        [BoxGroup("State"), ReadOnly]
        public Transform target;
        [BoxGroup("State"), ReadOnly]
        public float valueForeground = 50f;
        [BoxGroup("State"), ReadOnly]
        public float valueBackground = 150f;



        [FoldoutGroup("Configurations")]
        public RectTransform rectTransform;
        [FoldoutGroup("Configurations")]
        public RectTransform foregroundObj;
        [FoldoutGroup("Configurations")]
        public RectTransform backgroundObj;
        [FoldoutGroup("Configurations")]
        public Image foregroundImg;
        [FoldoutGroup("Configurations")]
        public Image backgroundImg;
        [FoldoutGroup("Configurations")]

        public float hideTime = 2f;

        private float hideTimeCounter = 0f;
        
        public void Setup(DamageController damageController)
        {
            hideTimeCounter = 0f;
            target = damageController.transform;
            valueForeground = damageController.HP;
            valueBackground = damageController.maxHP;
        }

        public void Update()
        {
            if (target != null && rectTransform != null)
            {
                Vector3 headPos = new Vector3(target.position.x, target.position.y + 2.2f, target.position.z);
                Vector3 screenPos = Camera.main.WorldToScreenPoint(headPos);
                rectTransform.position = screenPos;
                SetPercentage();
            }
            hideTimeCounter += Time.deltaTime;
            if(hideTimeCounter >= hideTime)
            {
                hideTimeCounter = 0f;
                gameObject.SetActive(false);
            }
        }

        void SetPercentage()
        {
            float width = backgroundObj.rect.width;
            float newWidth = (width * valueForeground) / valueBackground;
            if (newWidth > width) newWidth = width;
            if (newWidth < 0) newWidth = 0;
            foregroundObj.sizeDelta = new Vector2(newWidth, backgroundObj.rect.height);
        }
    }
}