ProgressBarFiller.cs

using Sirenix.OdinInspector;
using UnityEngine;

namespace Demos.SOArchApproach.CodeBase.ScriptableObjectsFramework
{
    public class ProgressBarFiller : MonoBehaviour
    {
        [SerializeField] private RectTransform.Axis movingAxis;

        private float startSize;

        private RectTransform tr;

        private float currentValue;

        private float targetValue;

        [SerializeField] private float increaseSpeed;

        [SerializeField] private float decreaseSpeed;

        // Start is called before the first frame update
        void Start()
        {
            tr = transform as RectTransform;
            startSize = movingAxis == RectTransform.Axis.Horizontal ? tr.rect.width : tr.rect.height;
            currentValue = 0;
            targetValue = 0;
        }

        // Update is called once per frame
        void Update()
        {
            if (targetValue > currentValue)
                currentValue = Mathf.MoveTowards(currentValue, targetValue, increaseSpeed * Time.deltaTime);
            else
                currentValue = Mathf.MoveTowards(currentValue, targetValue, decreaseSpeed * Time.deltaTime);
            float newWidth = currentValue * startSize;
            tr.SetSizeWithCurrentAnchors(movingAxis, newWidth);
        }

        [Button]
        public void SetTargetValue(float value)
        {
            targetValue = value;
        }
    }
}