[設計模式]觀察者模式 Unity下簡單示例

發佈者：定義事件成員，以及事件觸發函數

using UnityEngine;
using System.Collections;
using System;

public class BirdController : MonoBehaviour
{

	// 定義事件成員
	public event Action GameOver;
	public event Action<int> ScoreAdd;

	private void OnGUI()
	{
		// 事件觸發
		if (GUI.Button(new Rect(10, 10, 150, 100), "投降"))
		{
			GameOver?.Invoke();
		}
		if (GUI.Button(new Rect(10, 200, 150, 100), "加10分"))
		{
			ScoreAdd?.Invoke(10);
		}
	}
}

訂閱者：定義事件處理函數，訂閱事件

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

public class GameUI : MonoBehaviour
{
	private BirdController m_BirdController;

	int m_Score = 0;

	// Use this for initialization
	void Start()
	{
		m_BirdController = GameObject.Find("bird").GetComponent<BirdController>();
		AddListener();
	}

	void OnDestroy()
	{
		RemoveListener();
	}

	// 訂閱
	void AddListener()
	{
		m_BirdController.GameOver += OnGameOver;
		m_BirdController.ScoreAdd += OnScoreAdd;
	}

	// 取關事件
	void RemoveListener()
	{
		m_BirdController.GameOver -= OnGameOver;
		m_BirdController.ScoreAdd -= OnScoreAdd;
	}

	void OnGameOver()
	{
		Debug.Log("你輸了");
	}

	void OnScoreAdd(int score)
	{
		m_Score += score;
		Debug.Log("分數：" + m_Score);
	}
}