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隐藏非活动属性

要仅显示活动的 System object™ 属性,请使用 isInactivePropertyImpl 方法。此方法用于指定某个属性是否为非活动属性。非活动属性是不因其他属性的值而影响 System object 的属性。当您将某个属性传递给 isInactiveProperty 方法,而此方法返回 true 时,则该属性为非活动属性,不会在调用 disp 函数时显示。

指定非活动属性

此示例使用 isInactiveProperty 方法检查从属属性的值。对于此 System object,如果 UseRandomInitialValue 属性设置为 true,则 InitialValue 属性是无关的。此 isInactiveProperty 方法会检查该情况,如果 UseRandomInitialValuetrue,则返回 true 以隐藏非活动的 InitialValue 属性。

methods (Access = protected)
  function flag = isInactivePropertyImpl(obj,propertyName)
    if strcmp(propertyName,'InitialValue')
      flag = obj.UseRandomInitialValue;
    else
      flag = false;
    end
  end
end

包含非活动属性方法的完整类定义文件

classdef Counter < matlab.System
  % Counter Increment a counter
  
  % These properties are nontunable. They cannot be changed
  % after the setup method has been called or when the
  % object is running.
  properties (Nontunable)
    % Allow the user to set the initial value
    UseRandomInitialValue = true
    InitialValue = 0
  end
  
  % The private count variable, which is tunable by default
  properties (Access = private)
    pCount
  end
  
  methods (Access = protected)
    % Increment the counter and return its value 
    % as an output
    function c = stepImpl(obj)
      obj.pCount = obj.pCount + 1;
      c = obj.pCount;
    end

    % Reset the counter to either a random value or the initial
    % value.
    function resetImpl(obj)
      if obj.UseRandomInitialValue
        obj.pCount = rand();
      else
        obj.pCount = obj.InitialValue;
      end
    end

    % This method controls visibility of the object's properties
    function flag = isInactivePropertyImpl(obj,propertyName)
      if strcmp(propertyName,'InitialValue')
        flag = obj.UseRandomInitialValue;
      else
        flag = false;
      end
    end
  end
end

另请参阅