StickerManager.cs

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

public class StickerManager : MonoBehaviour
{
    static StickerManager _instance;
    Dictionary<string, List<Sticker>> _stickers = new Dictionary<string, List<Sticker>>();
    List<string> _shownStickers = new List<string>();

    void Awake()
    {
        _instance = this;
    }

    public static Transform Canvas
    {
        get { return _instance.transform; }
    }

    public static void RegisterSticker(Sticker sticker)
    {
        if (!_instance._stickers.ContainsKey(sticker.Tag))
            _instance._stickers.Add(sticker.Tag, new List<Sticker>());

        _instance._stickers[sticker.Tag].Add(sticker);

        sticker.Shown = _instance._shownStickers.Contains(sticker.Tag);
    }

    public static void UnregisterSticker(Sticker sticker)
    {
        _instance._stickers[sticker.Tag].Remove(sticker);
    }

    public static void ShowStickers(string tag)
    {
        if (_instance._shownStickers.Contains(tag))
            return;

        _instance._shownStickers.Add(tag);

        if (!_instance._stickers.ContainsKey(tag))
            return;

        for (int i = 0; i < _instance._stickers[tag].Count; i++)
            _instance._stickers[tag][i].Shown = true;
    }

    public static void HideStickers(string tag)
    {
        if (!_instance._stickers.ContainsKey(tag))
            return;

        for (int i = 0; i < _instance._stickers[tag].Count; i++)
            _instance._stickers[tag][i].Shown = false;

        _instance._shownStickers.Remove(tag);
    }

    public static void HideAllStickers()
    {
        for (int i = 0; i < _instance._shownStickers.Count; i++)
        {
            if (!_instance._stickers.ContainsKey(_instance._shownStickers[i]))
                continue;

            for (int j = 0; j < _instance._stickers[_instance._shownStickers[i]].Count; j++)
                _instance._stickers[_instance._shownStickers[i]][j].Shown = false;
        }

        _instance._shownStickers.Clear();
    }
}