qt在动态库里面加载widget的例子

testDll和testExe项目

备注：windows下dll内不需要new QApplication, linux和mac下面需要在动态库里面new QApplication

testdll.h

 #ifndef TESTDLL_H

 #define TESTDLL_H

 #include"testDll_global.h"

 extern "C" TESTDLLSHARED_EXPORT void initApp(void);

 extern "C" TESTDLLSHARED_EXPORT void showDlg(void);

 extern "C" void cleanApp(void);

 class QApplication;

 static QApplication* shareApplication;

 #endif//TESTDLL_H

testDll_global.h

 #ifndef TESTDLL_GLOBAL_H

 #define TESTDLL_GLOBAL_H

 #include <QtCore/qglobal.h>

 #if defined(TESTDLL_LIBRARY)

 #  define TESTDLLSHARED_EXPORT Q_DECL_EXPORT

 #else

 #  define TESTDLLSHARED_EXPORT Q_DECL_IMPORT

 #endif

 #endif // TESTDLL_GLOBAL_H

testdll.cpp

#include<QApplication>

#include<QMessageBox>

#include"TestDll.h"

#include"Form.h"

extern "C" TESTDLLSHARED_EXPORT void initApp(void)

{

    shareApplication=NULL;

}

extern "C" TESTDLLSHARED_EXPORT void showDlg(void)

{

    if( NULL == shareApplication )

    {

        int argc=;

        //windows下注释掉

//        shareApplication = new QApplication(argc,NULL);

        Form* pForm=new Form;

        pForm->show();

//        shareApplication->exec();

    }

}

extern "C" void cleanApp(void)

{

    if( NULL != shareApplication )

    {

        QMessageBox::information(NULL,"","appdestroyed",);

//        shareApplication->quit();

//        shareApplication=NULL;

    }

}

testExe的测试cpp里面

 void MainWindow::on_pushButton_clicked()

 {

     QLibrary dll("testDll");

     if( !dll.load() ) return;

     typedef void(*DLL_INIT_APP)();

     typedef void(*DLL_SHOW_DLG)();

     DLL_INIT_APP dll_initApp = (DLL_INIT_APP)dll.resolve("initApp");

     DLL_SHOW_DLG dll_showDlg= (DLL_SHOW_DLG)dll.resolve("showDlg");

     dll_initApp();

     dll_showDlg();

 }