即使我重载=运算符，也无法生成赋值运算符

Question

My class is polymorphic and should not be used to be ='d anyways. It has a member which is of type Font& and as a result the compiler cannot generate an = operator. So I just created dummy implementations of the assignment and copy constructor, put them in the private of the class, but it still warns me about assignment operator not able to get generated. How else can I get rid of this warning?

Thanks

Warning 9 warning C4512: 'AguiWidget' : assignment operator could not be generated c:\\users\\josh\\documents\\visual studio 2008\\projects\\agui\\alleg_5\\agui\\aguiwidget.hpp 250

Answer 1

The assignment operator that the compiler is warning you about is the one for your own class. What you have now is:

AguiWidget& operator=(const AguiFont &tmp);

What you need is:

AguiWidget& operator=(const AguiWidget &tmp);

Answer 2

You can disable it. This won't work, of course, if you're actually trying to use those operators.

Are you sure you got the signatures right? Did you make them for each class, base and deriveds?

Answer 3

Use boost::noncopyable .

class AGUI_CORE_DECLSPEC AguiWidget : private boost::noncopyable

NOTE:

boost::noncopyable will be enforced for all sub-classes as well.

EDIT:

Wow... that's one scary class...

Use the pimpl idiom to reduce code interdependencies and improve interface readability.

Also you should try to avoid protected member variables (as much as possible) as it breaks encapsulation.