Calling parent function from child class

[harryvermeulen]

Hello,

I have a class called 'VideoPlayer', in which I create an object of another class called 'MenuBar'.

In the 'MenuBar' class I handle mouse events. If one of the buttons in the 'MenuBar' object is clicked, I want to call a function in the 'VideoPlayer' object.

I figured I should send a pointer to the 'VideoPlayer' object to the 'MenuBar' object, so I can access the 'VideoPlayer' object's functions. However, when I include the header file for the 'VideoPlayer' class into the 'MenuBar' class, I get compiler errors:

1>ClCompile:
1>  hvMenuBar.cpp
1>.\src\VideoPlayer.h(51): error C2146: syntax error : missing ';' before identifier 'menu'
1>.\src\VideoPlayer.h(51): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>.\src\VideoPlayer.h(51): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

I guess I'm going about it wrong. Any way I try to make a link to the 'parent' class, I get into trouble. I think it's because I'm basically making an #include loop, which includes each other. Simply put I don't know how to do it.

If anyone could point me in the good direction, I'd be very grateful.

Kind regards,
Harry Vermeulen

[ne555]

http://www.cplusplus.com/forum/articles/10627/

[harryvermeulen]

Thank you for your reply. It's a very helpful article.

I'm not able to solve the problem though. If I forward declare the VideoPlayer class in the MenuBar class, I can define a pointer to a VideoPlayer object, but I can't call any of VideoPlayer's functions through the pointer. For example:

//hvMenuBar.h
//====================
class VideoPlayer;

class hvMenuBar {
    public:
         hvMenuBar::ButtonClicked();
         VideoPlayer *videoPlayer
}

//hvMenuBar.cpp
//====================
hvMenuBar::ButtonClicked() {
    videoPlayer->doFunction(); // <-- error C2027: use of undefined type 'VideoPlayer'
}

Would implementing include guards in all of my header files solve the problem?

[ne555]

You need to include in the cpp.

[harryvermeulen]

You are my hero. Works like a charm!

Thanks a lot.