Linker error with custom widgets

tanmay2227

hey i am getting a linker error when installing a custom widget
plus my widget is not visible in qtcreator and only visible in qt designer . please help me . i have used qt5.0 in win 7 and msvc compiler

linker errors are of this kind
mainwindow.obj:-1: error: LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall AnalogClock::AnalogClock(class QWidget *)" (_imp??0AnalogClock@@QAE@PAVQWidget@@@Z) referenced in function "public: void __thiscall Ui_MainWindow::setupUi(class QMainWindow *)" (?setupUi@Ui_MainWindow@@QAEXPAVQMainWindow@@@Z)

please help

tilsitt

Hi,

It looks like the symbols have not been exported when compiling AnalogClock. Could you please show the class declaration?

tanmay2227

#include <QDesignerCustomWidgetInterface>

class AnalogClockPlugin : public QObject, public QDesignerCustomWidgetInterface
{
Q_OBJECT
Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QDesignerCustomWidgetInterface" FILE "analogclock.json")
Q_INTERFACES(QDesignerCustomWidgetInterface)
public:
AnalogClockPlugin(QObject *parent = 0);

bool isContainer() const;
bool isInitialized() const;
QIcon icon() const;
QString domXml() const;
QString group() const;
QString includeFile&#40;&#41; const;
QString name(&#41; const;
QString toolTip() const;
QString whatsThis() const;
QWidget *createWidget(QWidget *parent);
void initialize(QDesignerFormEditorInterface *core);

private:
bool initialized;
};

though this is same as the custom widgetsexample of qt i have tried various versions but none are working
this is the pro file of my executing file

QT += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = tester
TEMPLATE = app

SOURCES += main.cpp
mainwindow.cpp

HEADERS += mainwindow.h

FORMS += mainwindow.ui
INCLUDEPATH += "C:\Qt\Qt5.0.1\5.0.1\msvc2010\examples\designer\customwidgetplugin"

i had also added the libs path but on that the program terminates without any reason

LIBS +=-L"C:\Qt\Qt5.0.1\Tools\QtCreator\bin\tester" -l"customwidgetplugin"

tilsitt

If you try this:
@
#ifdef EXPORT_MY_PLUGIN
#define MY_API Q_DECL_EXPORT
#else
#define MY_API Q_DECL_IMPORT
#endif

class MY_API AnalogClockPlugin
...
@

while adding EXPORT_MY_PLUGIN in the defines of your plugin project, does it change something?

tanmay2227

no the file is not compiling even and well the code is actually qt example only
so i think it is the deployment and installing which is the problem

Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Linker error with custom widgets