What software functionality requires triggering callback functions by adding or removing dynamic attributes?（matlab2020 code）

Question

"In MATLAB, it appears that only 'dynamic properties' can trigger built-in events（PropertyAdded/PropertyRemoved） when added or removed. For example, in the following code snippet. But from a product design perspective, the necessity of using the addition/removal of 'dynamic properties' to trigger callback functions for changing text in a figure is not very significant.

So, in which software requirements is it necessary to use the addition/removal of dynamic properties to trigger callback functions?"

---

%main.m
function main()
clear all
clc
import MyFigure.*  %Import packge

%Creat a figure object fig_obj
fig_obj=MyFigure([0.2,0.2,0.50,0.50]);

%Creat class AddDynoProFigHandlea;=AddDynoProp(fig_obj);
%pause;  %暂停

%Add 'dynamic properties'Data for fig_obj through object ab
ab.AddPropForMyFigure(fig_obj,'Data');

%Use findprop to obtain the meta.DynamicProperty object corresponding to the member 'Data'
m = fig_obj.findprop('Data');

%将函数set_Data的句柄指派到SetMethod成员上
m.SetMethod = @set_Data;

%成员Data的数据设置    
fig_obj.Data=peaks;

delete(ab);
end

MyFigure.m

%+MyFigure\@MyFigure\MyFigure.m
classdef  MyFigure<dynamicprops
    properties
        FigHandle;    %图形窗口句柄
        AxHandle;    %轴对象句柄
    end
    methods
        function obj = MyFigure (pos)  %构造函数
            if nargin > 0
                if length(pos) == 4
                    obj.FigHandle = figure('Unit','normalized','Position',pos,...
                        'Name','动态属性成员事件演示','NumberTitle','off',...
                        'MenuBar','none');
                else
                    error('Improper position')
                end
            end
            obj.AxHandle =axes('Parent',obj.FigHandle,...
                'Unit','normalized',...
                'Pos',[0.1,0.1,0.7,0.8]);
            uicontrol('Parent',obj.FigHandle,...
                'Unit','normalized',...
                'Pos',[0.82,0.1,0.15,0.1],...
                'Style','pushbutton',...
                'String','退出',...
                'Callback','close');
        end
    end
end

AddDynoProp.m

%+MyFigure\@AddDynoProp\AddDynoProp.m
classdef AddDynoProp < handle
    properties
        mp;  %动态属性成员对应的meta.DynamicProperty对象
    end
    methods
        %构造函数，evtobj为产生事件的对象
        function obj = AddDynoProp(evtobj)
            if nargin > 0
                %创建两个听众
                addlistener(evtobj,'PropertyAdded',@MyFigure.AddDynoProp.PropEvents);
                addlistener(evtobj,'PropertyRemoved',@MyFigure.AddDynoProp.PropEvents);
            end
        end
        %在对象evtobj上添加属性成员DynoPropName为产生事件的对象
        function AddPropForMyFigure(obj,evtobj,DynoPropName)
            obj.mp = evtobj.addprop(DynoPropName);
        end
        %析构函数
        function delete(obj)
            delete(obj.mp);  %删除动态属性成员
        end
    end
    methods (Static)
        %回调函数
        function PropEvents(src,evnt)
            switch evnt.EventName
                case 'PropertyAdded'
                    title(src.AxHandle,'PropertyAdded 事件发生了');
                case 'PropertyRemoved'
                    title(src.AxHandle,'PropertyRemoved 事件发生了');
                    set(src.AxHandle,'Visible','off');
            end
        end
    end
end

set_Data

function set_Data(obj,val)
obj.Data = val;
surf(obj.Data);  %绘制Data的曲面图
end