projectEli/Assets/Inventory System/Scripts/UI/DragWindowUI.cs

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

namespace SimpleInventorySystem
{
    public class DragWindowUI : MonoBehaviour, IDragHandler, IBeginDragHandler, IEndDragHandler, IPointerDownHandler
    {
        private RectTransform dragRectTransform;
        private Canvas canvas;
        private Image backgroundImage;
        private Color backgroundColor;
        public TextMeshProUGUI title;

        public void OnBeginDrag(PointerEventData eventData)
        {
            backgroundColor.a = .4f;
            backgroundImage.color = backgroundColor;
        }

        public void OnDrag(PointerEventData eventData)
        {
            dragRectTransform.anchoredPosition += eventData.delta / canvas.scaleFactor;
        }

        public void OnEndDrag(PointerEventData eventData)
        {
            backgroundColor.a = .8f;
            backgroundImage.color = backgroundColor;
        }

        public void OnPointerDown(PointerEventData eventData)
        {
            dragRectTransform.SetAsLastSibling();
        }

        public void CloseWindow()
        {
            //Destroy(dragRectTransform.gameObject);
            transform.parent.gameObject.SetActive(false);
        }

        void Awake()
        {
            dragRectTransform = transform.parent.GetComponent<RectTransform>();
            backgroundImage = GetComponent<Image>();
            backgroundColor = backgroundImage.color;
        }

        // Start is called before the first frame update
        void Start()
        {
            canvas = SimpleInventorySystem.InventorySystem.instance.inventoryUI;
        }

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

        }
    }
}