UIFramework learning (scattered records)

1. Creation of UIType class

indexOf("/") : Returns the index position of the first occurrence of the "/" character in this instance. The subscript of the instance starts from 0. If it is not found, -1 is returned.

indexOf("/", 7) : Returns the position of the first occurrence of "/" starting from index 7 in this instance. If not found, returns -1.

indexOf is from left to right, and lastIndexOf is from right to left. Although the search directions are different, the character subscripts still increase by 1 from left to right, starting from 0.

lastIndexOf("/") : Returns the index position of the last occurrence of "/" in this instance. That is, search from right to left to find the position of the first occurrence of "/". If it is not found, -1 is returned.

lastIndexOf("/", 7) : Returns the position of the last occurrence of "/" in the substring starting from index 0 to ending at index 7 in this instance. That is, search from right to left to find the position of the first occurrence of "/". If it is not found, -1 is returned.

subString : intercept the string. subString(7,2) means starting from subscript 7, intercepting a string of length 2, subString(7) means starting from subscript 7, intercepting to the end of the string. Name = path.Substring(path.LastIndexOf('/') + 1); The subscript is intercepted from the first character after /, which is our path name.

This is a class for UI panels where the name is retrieved from the prefab by address. After we load the address through resources.load, we can use path.Substring(path.LastIndexOf('/')+1) to perfectly solve the problem of clone after the name (the preset generated through instantiation has a clone)

/// <summary>
/// 存储单个Ui的信息，包括名字和路径
/// </summary>
public class UIType {
    /// <summary>
    /// UI名字
    /// </summary>
    public string Name { get; private set; }
    /// <summary>
    /// UI路径
    /// </summary>
    public string Path { get; private set; }


    //构造函数获取路径
    public UIType(string path) {
        Path = path;
        //找最后一个斜杠索引的位置， + 1为/后的位置，名字开头的第一个字符
        Name = path.Substring(path.LastIndexOf('/') + 1);
    }
}

2. Creation of BasePanel class

/// <summary>
/// 所有UI面板的父类，包含UI面板的状态信息
/// </summary>
public abstract class BasePanel
{
    /// <summary>
    /// UI信息
    /// </summary>
    public UIType UIType { get; private set;  }

    /// <summary>
    /// UI进行时所进行的操作，虚方法（方便继承），只会执行一次
    /// </summary>
    public virtual void OnEnter() { 
    
    }
    /// <summary>
    /// UI暂停时执行的操作
    /// </summary>
    public virtual void OnPuse() { }
    /// <summary>
    /// UI重新开始时执行的操作
    /// </summary>
    public virtual void OnResume() { }
    /// <summary>
    /// UI退出时执行的操作
    /// </summary>
    public virtual void OnExit() { }
}

3.Creation of UIManger class

public class UIManager
{
    /// <summary>
    /// 存储所有UI信息的字典，每一个UI信息都会对应一个gameObj
    /// </summary> 
    private Dictionary<UIType, GameObject> dicUI;

    //构造函数对其进行初始化
    public UIManager(){
        dicUI = new Dictionary<UIType, GameObject>();
    }
    /// <summary>
    /// 获取一个UI对象，传一个UUItype类，命名为type
    /// </summary>
    /// <param name="type">UI信息</param>
    /// <returns></returns>
    public GameObject GetSingleUI(UIType type) {
        //设置一个游戏物体父对象，查找游戏画布的名字
        GameObject parent = GameObject.Find("Canvas");
        //判断是否为空物体
        if(!parent){
            Debug.LogError("画布不存在，请仔细查找有无这个对象，返回为空");
            return null;
        }
        //单例：检查是否有，有就返回，没有就创建
        if (dicUI.ContainsKey(type))
            return dicUI[type];
        GameObject ui = GameObject.Instantiate(Resources.Load<GameObject>(type.Path), parent.transform);
        //则不带clone后缀（实例化生成会clone）
        ui.name = type.Name;
        return ui;
    }

    /// <summary>
    /// 销毁一个UI对象
    /// </summary>
    /// <param name="type">UI信息</param>
    public void DestroyUI(UIType type) {
        //有问题，递归了，容易造成死循环,若不递归，则下列两行代码位置互换
        if (dicUI.ContainsKey(type)) {

            DestroyUI(type);
            dicUI.Remove(type);        }

    }
}

(Note, there is a recursive loop bug)

Note : The C# language supports recursion , that is, a function can call itself . When using recursion , you need to define a condition for exiting from the function, otherwise it will enter an infinite loop .

Reference article:

https://blog.csdn.net/qq_40182225/article/details/79202710

[Unity] Usage of string-LastIndexOf (solve the clone behind the preset generated by instantiation)_Yemengshuo Development (VR) Blog-CSDN Blog