I want to use an SDK I got for using a scanner. I'm using Qt 5.3 with MingW32 (on Windows 7).
The very first test I wanted to build should just print the SDK version.
Here is my project file
QT += core
QT -= gui
TARGET = Kojak1
CONFIG += console
CONFIG -= app_bundle
KOJAKDIR = "C:/Program Files/Integrated Biometrics/IBScanUltimateSDK_x64"
TEMPLATE = app
INCLUDEPATH += $$KOJAKDIR/Include
SOURCES += main.cpp
LIBS +=-L$$KOJAKDIR/lib/ -lIBScanUltimate
and here is the source code
#include <QCoreApplication>
#include "stdio.h"
#include <windows.h>
#include "IBScanUltimateApi.h"
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
IBSU_SdkVersion sdk_version;
IBSU_GetSDKVersion(&sdk_version);
printf("%s %s",sdk_version.File,sdk_version.Product);
return a.exec();
}
Unforturnately I get the message
D:\devt\QTProjects\Kojak1\main.cpp:10: error: undefined reference to `IBSU_GetSDKVersion#4'
when trying to compile the program.
My lib directory does contain IBScanUltimate.lib and IBScanUltimate.dll.
Related
I have yocto dev environment setup, in which I can bitbake and run a simple c++ application in the target. Now I want to try with simple Qt application. When I execute bitbake-layers show-layers it shows meta-qt5 in the list...
meta-qt5
/home/prc1cob/repo/out/salt/kawa/../../..//os/external/meta-qt5 7
meta-oe
/home/prc1cob/repo/out/salt/kawa/../../../build/yocto/meta-openembedded/meta-oe
6
With this, I assume qt5 is already present in my yocto build.
How to write .bb file to build a simple HelloWorld qt application as below...
#include <QCoreApplication>
#include <QDebug>
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qDebug() << "Hello World";
return a.exec();
}
Thankyou!!
Yocto provides a great class qmake5 to compile QT projects based on QMake.
In order to use it create a .pro file for the project:
qtexample.pro
QT += core
SOURCES += qtexample.cpp
qtexample.cpp
#include <QCoreApplication>
#include <QDebug>
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qDebug() << "Hello World";
return a.exec();
}
Now, in your layer, you can add a simple recipe that compiles that project.
For example: meta-custom/recipes-project/qtexample
In qtexample folder create files folder and copy qtexample.pro and qtexample.cpp in it.
In qtexample folder directly create qtexample_0.1.bb recipe:
SUMMARY = "QT Example Recipe"
LICENSE = "CLOSED"
SRC_URI = "file://qtexample.pro \
file://qtexample.cpp"
DEPENDS += "qtbase"
RDEPENDS_${PN} += "qtwayland"
S = "${WORKDIR}"
inherit qmake5
You can change the version ofcourse (0.1).
The layout should look like this:
meta-custom/
├── recipes-project/
├── qtexample_0.1.bb
└── files/
├── qtexample.pro
└── qtexample.cpp
Then, bitbake qtexample should work and create a qtexample binary that you can find in ${WORKDIR}
I am relatively new to Qt and was going through many tutorials. Everything was fine. All scripts compiled and ran.
Then, at some point, I am getting the error for even a new Qt widget application created with Qt Creator 4.3.1:
C:\ \Documents\111\main.cpp:-1: In function 'int qMain(int, char**)':
C:\ \Documents\111\main.cpp:6: error: variable 'QApplication a' has initializer but incomplete type
QApplication a(argc, argv);
^
C:\ \Documents\111\main.cpp:11: warning: control reaches end of non-void function [-Wreturn-type]
}
^
I am not sure what happened, yet seems like some setups were messed up.
QApplication is included, and not missing in the script.
111.pro
# Project created by QtCreator 2018-02-23T01:36:28
QT += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = 111
TEMPLATE = app
DEFINES += QT_DEPRECATED_WARNINGS
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0
SOURCES += \
main.cpp \
mainwindow.cpp
HEADERS += \
mainwindow.h
FORMS += \
mainwindow.ui
main.cpp
#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();
}
mainview.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
}
MainWindow::~MainWindow()
{
delete ui;
}
It seems to me that this issue appeared after trying to run qt5.6_src.zip examples from https://en.ids-imaging.com/open-source.html.
Without completed code, I guess you need to add #include <QApplication> to main.cpp
The error message told you what is missing.
According to Qt's docs, the constructor's signature is QApplication(int &argc, char **argv).
Therefore, if you inherit from QApplication then the subclass's constructor must pass argc by reference. From your description, it appears that the constructor of your subclass is actually passing argc by value (i.e., int qMain(int, char**) ). That will cause some problems.
The issue is fixed by deleting the Qt folder and QtCreator folder in the <drive>:\Users\<username>\AppData\Roaming\QtProject and <drive>:\Users\<username>\AppData\Roaming\Qt. It stored incorrect settings, which I somehow setup by running open source scripts. For more information visit Where does QtCreator save its settings?.
I am back to Qt and C++ programming after a year break. I am trying to install boost library into Qt on Mac (10.9.4) and I am completely confused. This is what I did:
I installed boost using homebrew.
I see that hpp files are installed here:
/usr/local/Cellar/boost/1.55.0_2/include/boost
and libraries here:
/usr/local/Cellar/boost/1.55.0_2/lib
Now I start a new Qt console project.
the project file:
QT += core
QT -= gui
TARGET = testQt
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
SOURCES += main.cpp
INCLUDEPATH += /usr/local/Cellar/boost/1.55.0_2
And the main file:
#include <QCoreApplication>
#include <QtCore>
#include <iostream>
#include <QDebug>
#include <boost/regex.hpp>
using namespace std;
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
std::string line;
boost::regex pat( "^Subject: (Re: |Aw: )*(.*)" );
while (std::cin)
{
std::getline(std::cin, line);
boost::smatch matches;
if (boost::regex_match(line, matches, pat))
std::cout << matches[2] << std::endl;
}
return a.exec();
}
Not compiling. Issues:
Symbol(s) not found for architectures x86_64
linker command failed with exist code 1
Since I am absolutely noob with boost, did I do it right? If yes, why is it not compiling?
Thanks a lot!
You need to link with boost too!
LIBS += -L/usr/local/Cellar/boost/1.55.0_2/lib -lboost
Working with Qt 5 and QtQuick 2.0
.pro
# Add more folders to ship with the application, here
folder_01.source = qml/untitled
folder_01.target = qml
DEPLOYMENTFOLDERS = folder_01
# Additional import path used to resolve QML modules in Creator's code model
QML_IMPORT_PATH =
# If your application uses the Qt Mobility libraries, uncomment the following
# lines and add the respective components to the MOBILITY variable.
# CONFIG += mobility
# MOBILITY +=
#CONFIG += qt plugin
#QT += qml quick
# The .cpp file which was generated for your project. Feel free to hack it.
SOURCES += main.cpp \
../DummyClass.cpp \
../aa.cpp
# Installation path
# target.path =
# Please do not modify the following two lines. Required for deployment.
include(qtquick2applicationviewer/qtquick2applicationviewer.pri)
qtcAddDeployment()
HEADERS += \
../DummyClass.h \
../aa.h
main.cpp
#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"
#include "/home/***/qmllistproperties/DummyClass.h"
int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);
const char* ocuui = "OCUUI"; // #uri OCUUI
qmlRegisterType <DummyClass> (ocuui, 1, 0, "DummyClass");
QtQuick2ApplicationViewer viewer;
viewer.setMainQmlFile(QStringLiteral("qml/untitled/main.qml"));
viewer.showExpanded();
return app.exec();
}
qmlRegisterType is in QtQml. You have to include QtQml:
#include <QtQml>
I've tried to compile the following code using Qt(4.6.3) + MinGW:
#include <QtCore/QCoreApplication>
#include <exception>
int main(int argc, char *argv[])
{
throw std::runtime_error("");
QCoreApplication a(argc, argv);
return a.exec();
}
... and got this error:
..\untitled11\main.cpp:6: error: 'runtime_error' is not a member of 'std'
Project created from scratch(console application), the pro file:
QT += core
QT -= gui
TARGET = untitled11
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
SOURCES += main.cpp
Tried to compile this using Qt+MSVC2008 compiler - works fine.
This is a standard exception, have no idea why is missing.
<exception> defines only the base std::exceptionclass; if you want child classes like std::runtime_error, you must include the <stdexcept> header.