Load objects from dynamic library

[Trok]

Hi, I want load objects with dynamic library without result ;/
I add in *.pro file:

LIBS += -Lpath -lname

LIBS += -Lpath -lname

To copy to clipboard, switch view to plain text mode 

and in *.cpp or *.h

extern "C" class __declspec(dllimport) testclass{};

extern "C" class __declspec(dllimport) testclass{};

To copy to clipboard, switch view to plain text mode 

It doesn't work. Why? Does it good prepare?

[shentian]

I'm not sure about the 'extern "C"'. And I'd use macros as explained here.

Anyway, what does not work? Do you get a linker error or a runtime error?

[Trok]

My program not complie ;/ I haven't any reports from debugger.
How can I use Q_DECL_IMPORT in my file who import library?
Btw:

LIBS += -LC:\Documents and Settings\bla\Pulpit\Qt Progs\LoaderObj\debug -lLoaderObj

LIBS += -LC:\Documents and Settings\bla\Pulpit\Qt Progs\LoaderObj\debug -lLoaderObj

To copy to clipboard, switch view to plain text mode 

is it correctly? It isn't building me now.

[spirit]

do you write this library by yourself? if yes read this and modify it.
maybe QLibrary also can help you.

[Trok]

Hi, I use QLibrary, and have some problem with action.
It's my code:
1.In *.dll

void LOADEROBJSHARED_EXPORT kamil()
{}

void LOADEROBJSHARED_EXPORT kamil()
{}

To copy to clipboard, switch view to plain text mode 

2. In app

typedef void (*AvgFunction)();
    QMessageBox kamil;
    QLibrary library("LoaderObj.dll");
    library.load();
    AvgFunction avg = (AvgFunction) library.resolve("kamil");
     if (avg)
        kamil.setText("good");
     else
        kamil.setText("bad");
 
       kamil.exec();

typedef void (*AvgFunction)();
    QMessageBox kamil;
    QLibrary library("LoaderObj.dll");
    library.load();
    AvgFunction avg = (AvgFunction) library.resolve("kamil");
     if (avg)
        kamil.setText("good");
     else
        kamil.setText("bad");

       kamil.exec();

To copy to clipboard, switch view to plain text mode 

Why it don't laod my function while load library? ;/

[sumitgogna]

I am having similar problems. I am new to libs and Qt. Anyone plz solve this problem.

[yogeshgokul]

Why it don't laod my function while load library? ;/

You have to load first the library and then methods.

[kuzulis]

For load classes from dynamic library see this link
http://www.prog.org.ru/topic_8259_0.html

PS: Russian language

[yogeshgokul]

PS: Russian language

Impossible for most of us.
But QLibrary::resolve() can resolve all exported symbols. Just remember you have to add this prefix @ the time of exporting symbols from dll.
__declspec(dllexport) ///FOR WINDOWS ONLY

[kuzulis]

Impossible for most of us.

Use http://translate.google and you will be a great happiness

[wysota]

I am having similar problems. I am new to libs and Qt. Anyone plz solve this problem.

Could you explain the problem? What errors do you get?