C++ - 我如何从类的构造函数初始化一个单独的类的构造函数？

Question

基本上我想实现是班上geneticAlgorithm

创建类deltaKinematics的地方（私人）实例在geneticAlgorithm.h文件我有：

class DeltaKinematics; //class is defined in separate linked files 

class GeneticAlgorithm { 
    //private 
    DeltaKinematics deltaRobot; 

public: 

    GeneticAlgorithm(); //constructor 

}; 

这是所有罚款，但是当我去申报GeneticAlgorithm构造函数，我不知道如何来建构DeltaKinematics

的情况下这是geneticAlgorithm.cpp构造：

GeneticAlgorithm::GeneticAlgorithm(){ //The error given on this line is "constructor for 'GeneticAlgorithm' must explicitly initialize the member 'deltaRobot' which does not have a default constructor" 

    DeltaKinematics deltaRobot(100); //this clearly isn't doing the trick 

    cout << "Genetic Algorithmic search class initiated \n"; 
} 

我该如何去初始化本地实例呢？

Answer 1

成员初始化列表：

GeneticAlgorithm::GeneticAlgorithm() : deltaRobot(100) { 
} 

Answer 2

GeneticAlgorithm::GeneticAlgorithm() : deltaRobot(100) { 
    cout << "Genetic Algorithmic search class initiated \n"; 
} 

注意:构造函数名后：它是类的成员变量的数据初始化序列的开始。它们显示为对其构造函数的调用，并带有要传递的参数，并且应该与声明的顺序相同。