一：目的
在制作游戏过程中，UI界面都是必不可少的，多则上百个少则几个，如果这些UI界面都放在场景里（如下图所示），那么运行的时候会占用大量的内存
一般都是将每一个UI界面制作成一个Prefab动态的进行显示隐藏，加载卸载
所以我们需要一个管理器统一管理UI的相关操作
二：解决的问题及优点
——不需要创建UI画布和UI相机，动态创建并设置属性
——管理每一个UI界面的层级
——打开和关闭UI界面
——查找某一个UI界面
三：使用方法
——将所有UI制作成预制体统一放在Resources—Prefabs—UI文件夹下
——所有的UI预制体都需要与挂载在身上的脚本名相同
——所有的UI预制体身上的脚本都需要继承UIBase基类
——使用UIMgr.Ins.XXX
UIMgr.Ins.OpenUI<UI_Main>(); UIMgr.Ins.CloseUI<UI_Main>(); UIMgr.Ins.TopUI;
——根据不同项目需求设置UI画布的缩放：UIMgr.Ins.SetCanvasScaler()
四：代码实现
using UnityEngine;
using UnityEngine.UI;
using System.Collections.Generic;
using UnityEngine.EventSystems;
/// <summary>
/// UI基类
/// </summary>
public class UIBase : MonoBehaviour
{
/// <summary>
/// 打开UI时
/// </summary>
public virtual void OnView()
{
transform.SetAsLastSibling();
gameObject.SetActive(true);
}
/// <summary>
/// 关闭UI时
/// </summary>
public virtual void OnDisView()
{
gameObject.SetActive(false);
}
}
/// <summary>
/// UI管理器
/// </summary>
public class UIMgr : Singleton<UIMgr>
{
public const string UIDir = "Prefabs/UI/";//UI目录
//渲染UI的画布
private Canvas uiCanvas;
public Canvas UICanvas { get { return uiCanvas; } }
//渲染UI的相机
private Camera uiCamera;
public Camera UICamera { get { return uiCamera; } }
//显示在最顶部的UI
private UIBase topUI;
public UIBase TopUI { get { return topUI; } }
private Dictionary<string, UIBase> uiDict = new Dictionary<string, UIBase>();//场景中的UI
protected override void Init()
{
base.Init();
if (uiCamera == null)
{
uiCamera = CreateUICamera();
}
if (uiCanvas == null)
{
uiCanvas = CreateUICanvas();
}
//设置Canvas缩放
SetCanvasScaler(new Vector2(750, 1334), false);
}
/// <summary>
/// 打开UI
/// </summary>
public T OpenUI<T>(string uiRoot = "")
where T : UIBase
{
string uiName = typeof(T).Name;
if (!uiDict.ContainsKey(uiName))
{
CreateUI(uiName, uiRoot);
}
UIBase ui = uiDict[uiName];
ui.OnView();
FindTopUI();
return ui as T;
}
/// <summary>
/// 关闭UI
/// </summary>
public void CloseUI(string uiName, bool destroy = false)
{
if (!uiDict.ContainsKey(uiName))
{
Debug.LogError("场景中没有此UI：" + uiName);
return;
}
if (destroy)
{
GameObject.Destroy(uiDict[uiName].gameObject);
uiDict.Remove(uiName);
}
else
{
uiDict[uiName].OnDisView();
}
FindTopUI();
}
/// <summary>
/// 关闭UI
/// </summary>
public void CloseUI<T>(bool destroy = false)
{
string uiName = typeof(T).Name;
if (!uiDict.ContainsKey(uiName))
{
Debug.LogError("场景中没有此UI：" + uiName);
return;
}
if (destroy)
{
GameObject.Destroy(uiDict[uiName].gameObject);
uiDict.Remove(uiName);
}
else
{
uiDict[uiName].OnDisView();
}
FindTopUI();
}
/// <summary>
/// 查找UI
/// </summary>
public T FindUI<T>()
where T : UIBase
{
string uiName = typeof(T).Name;
if (!uiDict.ContainsKey(uiName))
{
Debug.LogError("场景中没有此UI：" + uiName);
return default;
}
return uiDict[uiName] as T;
}
/// <summary>
/// 查找最顶部的UI
/// </summary>
private void FindTopUI()
{
for (int i = uiCanvas.transform.childCount - 1; i >= 0; i--)
{
if (uiCanvas.transform.GetChild(i).GetComponent<UIBase>() != null
&& uiCanvas.transform.GetChild(i).gameObject.activeSelf)
{
topUI = uiCanvas.transform.GetChild(i).GetComponent<UIBase>();
break;
}
}
}
/// <summary>
/// 设置Canvas缩放
/// </summary>
/// <param name="referResolution">参考的分辨率</param>
/// <param name="isLandscape">是否为横屏</param>
public void SetCanvasScaler(Vector2 referResolution, bool isLandscape)
{
CanvasScaler canvasScaler = uiCanvas.GetComponent<CanvasScaler>();
canvasScaler.uiScaleMode = CanvasScaler.ScaleMode.ScaleWithScreenSize;
canvasScaler.matchWidthOrHeight = isLandscape ? 1 : 0;
canvasScaler.referenceResolution = referResolution;
}
/// <summary>
/// 创建UI
/// </summary>
private void CreateUI(string uiName, string uiRoot)
{
string path = UIDir + uiName;
GameObject uiPrefab = Resources.Load<GameObject>(path);
if (uiPrefab == null)
{
Debug.LogError("UI不存在：" + path);
return;
}
UIBase uiBase = GameObject.Instantiate(uiPrefab, uiRoot == "" ? uiCanvas.transform : GameObject.Find(uiRoot).transform).GetComponent<UIBase>();
uiBase.gameObject.name = uiName;
uiDict.Add(uiName, uiBase);
}
/// <summary>
/// 创建UI画布
/// </summary>
private Canvas CreateUICanvas()
{
GameObject uiCanvas = new GameObject("UICanvas");
uiCanvas.layer = 5;
Canvas canvas = uiCanvas.AddComponent<Canvas>();
canvas.renderMode = RenderMode.ScreenSpaceCamera;
canvas.worldCamera = uiCamera;
uiCanvas.AddComponent<CanvasScaler>();
uiCanvas.AddComponent<GraphicRaycaster>();
GameObject eventSystem = new GameObject("EventSystem");
eventSystem.AddComponent<EventSystem>();
eventSystem.AddComponent<StandaloneInputModule>();
eventSystem.transform.SetParent(uiCanvas.transform);
GameObject.DontDestroyOnLoad(uiCanvas);
return uiCanvas.GetComponent<Canvas>();
}
/// <summary>
/// 创建UI相机
/// </summary>
private Camera CreateUICamera()
{
GameObject uiCamera = new GameObject("UICamera");
Camera camera = uiCamera.AddComponent<Camera>();
camera.clearFlags = CameraClearFlags.Depth;
camera.cullingMask = 1 << 5;
camera.orthographic = true;
camera.depth = 0;
GameObject.DontDestroyOnLoad(uiCamera);
return camera;
}
}
图片来源：http://www.lyouxi.com/ 手游