using a custom widget

[GrahamLabdon]

Hi
So I have a custom widget and want to use it in another project.
In the .pro file for the new project I have

LIBS += C://QTProjects/cccc-build-desktop/debug/mycustomwidgetplugin.dll

LIBS += C://QTProjects/cccc-build-desktop/debug/mycustomwidgetplugin.dll

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When I compile the project I get

debug/MainWindow.o:C:\QTProjects\cccc-build-desktop/./ui_MainWindow.h:43: undefined reference to `MyCustomWidget::MyCustomWidget(QWidget*)'

debug/MainWindow.o:C:\QTProjects\cccc-build-desktop/./ui_MainWindow.h:43: undefined reference to `MyCustomWidget::MyCustomWidget(QWidget*)'

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Any ideas?

Graham

[high_flyer]

did you specify in your project where to find the headers of your custom widgets?

[GrahamLabdon]

Hi
I have hard coded these for now
#include "C:/QTProjects/MyCustomWidget/MyCustomWidget.h"

[high_flyer]

where?
The error comes from an ui file - and it gets generated by the uic... if you are using your custom widget there - you should promote a widget to your custom widget so that the uic will include the correct file.

[GrahamLabdon]

hi
I have now added the include path the .pro file
My custom widget is built in a dll and is accessible in QtDesigner (although not in QtCreator)
To get my application that uses the custom widget to compile I added an include path to the . pro file
I also added the dll to the LIBS -

#-------------------------------------------------
#
# Project created by QtCreator 2011-03-21T11:54:03
#
#-------------------------------------------------
 
QT       += core gui
 
TARGET = cccc
TEMPLATE = app
 
 
SOURCES += main.cpp\
        MainWindow.cpp
 
HEADERS  += MainWindow.h
 
FORMS    += MainWindow.ui
 
INCLUDEPATH = C:/QTProjects/MyCustomWidget
win32::LIBS += C:/QTProjects/MyCustomWidget-build-desktop/release/mycustomwidgetplugin.dll

#-------------------------------------------------
#
# Project created by QtCreator 2011-03-21T11:54:03
#
#-------------------------------------------------

QT       += core gui

TARGET = cccc
TEMPLATE = app


SOURCES += main.cpp\
        MainWindow.cpp

HEADERS  += MainWindow.h

FORMS    += MainWindow.ui

INCLUDEPATH = C:/QTProjects/MyCustomWidget
win32::LIBS += C:/QTProjects/MyCustomWidget-build-desktop/release/mycustomwidgetplugin.dll

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When I build I get a undefined reference -
/ui_MainWindow.h:43: undefined reference to `MyCustomWidget::MyCustomWidget(QWidget*)'

I am struggling to understand why this is

Any help appreciated

Graham

[high_flyer]

I am struggling to understand why this is

read my last post again.

[GrahamLabdon]

Hi
In Qt Designer I can see my custom widget and can drag it onto a form.
This generates a ui file with an #include for the custom widget, which is located because of the INCLUDEPATH directive in the .pro file.
If I drag a widget onto the form and try to promote it I get an error stating that the class already exists
So I am confused!!

[high_flyer]

Hi
In Qt Designer I can see my custom widget and can drag it onto a form.
This generates a ui file with an #include for the custom widget, which is located because of the INCLUDEPATH directive in the .pro file.

That piece of information you want to give at the beginning, and that is - that you have a designer plug in for your custom widget!!
So there is no need for promotion.

does your custom widget have a constructor that take a QWidget parent defined?
Post the header for your custom widget.

[GrahamLabdon]

Header File

#ifndef MYCUSTOMWIDGET_H
#define MYCUSTOMWIDGET_H
 
#include <QtGui/QWidget>
 
class MyCustomWidget : public QWidget
{
    Q_OBJECT
 
public:
    MyCustomWidget(QWidget *parent = 0);
};
 
#endif

#ifndef MYCUSTOMWIDGET_H
#define MYCUSTOMWIDGET_H

#include <QtGui/QWidget>

class MyCustomWidget : public QWidget
{
    Q_OBJECT

public:
    MyCustomWidget(QWidget *parent = 0);
};

#endif

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cpp

#include "MyCustomWidget.h"
 
MyCustomWidget::MyCustomWidget(QWidget *parent) :
    QWidget(parent)
{
}

#include "MyCustomWidget.h"

MyCustomWidget::MyCustomWidget(QWidget *parent) :
    QWidget(parent)
{
}

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Thanks for your help!

[high_flyer]

ok, show the include section of ui_MainWindow.h

[GrahamLabdon]

Here ya go

#ifndef UI_MAINWINDOW_H
#define UI_MAINWINDOW_H
 
#include <QtCore/QVariant>
#include <QtGui/QAction>
#include <QtGui/QApplication>
#include <QtGui/QButtonGroup>
#include <QtGui/QHeaderView>
#include <QtGui/QMainWindow>
#include <QtGui/QMenuBar>
#include <QtGui/QStatusBar>
#include <QtGui/QToolBar>
#include <QtGui/QWidget>
#include "MyCustomWidget.h"

#ifndef UI_MAINWINDOW_H
#define UI_MAINWINDOW_H

#include <QtCore/QVariant>
#include <QtGui/QAction>
#include <QtGui/QApplication>
#include <QtGui/QButtonGroup>
#include <QtGui/QHeaderView>
#include <QtGui/QMainWindow>
#include <QtGui/QMenuBar>
#include <QtGui/QStatusBar>
#include <QtGui/QToolBar>
#include <QtGui/QWidget>
#include "MyCustomWidget.h"

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