How to use an array within a class?

Question

I'm currently designing some code on QT that is built across multiple source. I want to create an array in one source and be able to access it in another source.

Currently in my Header I have class

Array_Class : public QString
{
public:
    static QString Data_Array [2];
};

I don't think I need a constructor as I'm going to "populate" the array before I read it.

currently in my source.cpp I have

Array_Class::Data_Array[0]= "foo";
Array_Class::Data_Array[1]= "bar";

however this gives me the error message undefined reference to "Array_Class::Data_Array". What am I missing? thanks

https://stackoverflow.com/questions/12573816/what-is-an-undefined-reference-unresolved-external-symbol-error-and-how-do-i-fix — Cory Kramer, Aug 03 '15 at 15:15
also https://stackoverflow.com/questions/195207/unresolved-external-symbol-on-static-class-members — Cory Kramer, Aug 03 '15 at 15:15

score 3 · Accepted Answer · answered Aug 03 '15 at 15:16

So far, you have only declared your array:

Array_Class : public QString
{
public:
    static QString Data_Array [2]; // -> only a declaration!
};

In order to use it, you must now define it. To do this, you need to place somewhere in your .cpp:

QString Array_Class::Data_Array [2];

How to use an array within a class?

1 Answers1