A couple months ago, I decided I'd like to learn some basic coding skills, so I bought a book called "Beginning C++ Through Game Programming." Most of the concepts seemed very intuitive and well-explained, but now that I'm nearing the end (I'm on ch.9 of 10), I'm starting to feel overwhelmed. I guess I shouldn't have expected to be able to do this all on my own.
I was hoping someone could help me understand this program that's supposed to demonstrate object containment. The book usually gives pretty thorough explanations of the example programs, but in this case, I felt that the explanation was lacking. I think what's really throwing me is the m_Critters vector. Up until this point in the book, all of the vectors have been <int> or <string> type vectors, and I don't really understand how a vector can be declared as a <Critter> type (which is the name of a class in the program). It seems like it should just be a string vector, since it seems to be holding strings.
I tried changing this
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cout << iter->GetName() << " here.\n";
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to this
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cout << *iter << " here.\n";
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so I could see what exactly was in the vector, but I got a compile error. I think it would be helpful if I could see some other examples of how a vector can contain class members. If someone could direct me to a tutorial that explains these concepts, I'd really appreciate it.
Thanks everyone. Here's the program:
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//Critter Farm
//Demonstrates object containment
#include <iostream>
#include <string>
#include <vector>
using namespace std;
class Critter
{
public:
Critter(const string& name = "");
string GetName() const;
private:
string m_Name;
};
Critter::Critter(const string& name):
m_Name(name)
{}
inline string Critter::GetName() const
{
return m_Name;
}
class Farm
{
public:
Farm(int spaces = 1);
void Add(const Critter& aCritter);
void RollCall() const;
private:
vector<Critter> m_Critters;
};
Farm::Farm(int spaces)
{
m_Critters.reserve(spaces);
}
void Farm::Add(const Critter& aCritter)
{
m_Critters.push_back(aCritter);
}
void Farm::RollCall() const
{
for (vector<Critter>::const_iterator iter = m_Critters.begin();
iter != m_Critters.end();
++iter)
{
cout << iter->GetName() << " here.\n";
}
}
int main()
{
Critter crit("Poochie");
cout << "My critter's name is " << crit.GetName() << endl;
cout << "\nCreating critter farm.\n";
Farm myFarm(3);
cout << "\nAdding three critters to the farm.\n";
myFarm.Add(Critter("Moe"));
myFarm.Add(Critter("Larry"));
myFarm.Add(Critter("Curly"));
cout << "\nCalling Roll...\n";
myFarm.RollCall();
return 0;
}
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