How to run a C++ code in Qt?

[SGaist]

Did you implement anything in MainWindow ?

[Rela]

@Rela
Yes, its an algorithm here written in C++.

[SGaist]

I can't really read it because of all the whited out parts. But the first thing I'd do is check that you don't do anything funky in there. Remove what's not related to your algorithm from main and try to run that. Once it's good, bring back the Qt parts.

[Rela]

@SGaist
Sorry for white space, I have to remove some function names. The algorithm is 2820 lines, and I think each line is needed to output the result. Do you mean i remove the algorithm completely and just remain
#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();}

in main.cpp
I did that and the here is the output.

[SGaist]

Looks like there's no error there. But I meant the other way around. Run just your algorithm code. The error is there somewhere. And you should put a break point at the start so you can go step by step until it breaks.

[Rela]

@SGaist
The algorithm code gives result in MSVC2013.

[SGaist]

Then there's something fishy going on with MinGW or you're lucky with Visual Studio. Without any code I can't possibly help you find why it's crashing only with MinGW.

[Rela]

@SGaist
The above output was the debug using "Desktop Qt 5.5.1 MSVC2013 64 bit". I didnt debug with MinGW. The problem is the way I use to get the results in UI.
I tried a simple project to print out "Hello world", the C++ code written in MSVC gives output. Could you please take a look at my files:
Here are the content of C++ all files.
main.cpp
Bucky9.cpp
stdafx.cpp
targetver.h
stdafx.h
Now I created a Qt widget project, and I added the C++ code stdafx.h, targetver.h, and stdfx.cpp files using "Add existing Files" to the header and source. I didnt add Bucky9.cpp and main.cpp. Instead, I coppied the main.cpp C++ codes in the Qt main.cpp file with a little changes of all files.
(Changes: 1- Bucky9 is not included in Qt.
2- In stdafx.h #include <char.h> instead of <tchar.h>
3- Including #include "stdafx.h" in mainwindow.cpp.

Here are the content of all files in Qt project:
main.cpp
mainwindow.cpp
stdafx.cpp
stdafx.h
targetver.h
mainwindow.h

When I debug it it start debugging and when I click on Run it gives the "Hello world" in "Application output" here
Now I just want to get the "Hello world" in "mainwindow.ui" instead of in "Application output". Could you tell me how to do that?

[SGaist]

First thing: don't use cout since it will send the text to the console.

You can simply put a QLabel with hello world as text as central widget of your MainWindow class.

[Rela]

@SGaist
I am going to print the result of the C++ code in UI. For "Hello world" here is the Qt using QLabel written in "main.cpp" after "Debug". The C++ files (stdf.h, targetver.h, stdafx.cpp) were added, but I am not sure if the "Hello world" is the result of C++ code or not.

Again here is my C++ project in MSVC2013.
After I created Qt widget, I added "O_PS .H ", "stdaf.h ", "targetver.h ", " po .cpp", and "stdaf.cpp ". The code was copied in "#main.cpp" to have one main function. As input data, a model.txt file also a path of text file was added in the run "Arguments" of "Desktop Qt 5.5.1 MSVC2013 64 bit. It gave error that it cannot find the headers files, and I copied all of them in the Qt project folder. Here is the "Application Output".
In MSVC, it gives some values as outputs, I added a label to ui and wrote QLabel instead of one of the values "cout", like "Hello world". It gives this error. Here is the line that error show, the cout is comment and instead Qlabel was used.

// QLabel* label=new QLabel(para(i,0));
        label->setAlignment(Qt::AlignCenter);
        QWidget* widget=new QWidget;
        QHBoxLayout* layout=new QHBoxLayout;
         layout->addWidget(label);
         widget->setLayout(layout);
         widget->show();
        //for(i= 0; i<para.IDim(); i++)
             //cout << para(i,0) << "\t" <<para(i,1) << endl;

[SGaist]

Because para returns a double and not a string.

You should use QString::number(para(i,0))

[Rela]

@SGaist
This code in "main.cpp" outputs the area and prime of a circle in which QString::number(); is used to return float.

#include "mainwindow.h"
#include <QApplication>

#include <QString>
#include <QHBoxLayout>
#include <QLabel>
#include <QWidget>

#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    int radius = 3; //radius of circle
        float square; //area of circle
        float edge; //perimeter of circle
     square = 3.14 * radius*radius;
     edge = 2 * 3.14 *radius;

        //cout << "Circle are= " << area << endl;
        //cout << "Circle perimeter= " << perime;

        // Show area
        QString area = QString::number(square);
        QLabel* arlabel=new QLabel(area);
        // create horizontal layout
        arlabel->setAlignment(Qt::AlignCenter);
        QHBoxLayout* arlayout=new QHBoxLayout;
        // and add label to it
        arlayout->addWidget(arlabel);
        QWidget* arwidget=new QWidget;
        // set layout to widget
        arwidget->setLayout(arlayout);
        arwidget->show();

        // Show perime
        QString perime = QString::number(edge);
        QLabel* pelabel=new QLabel(perime);
        pelabel->setAlignment(Qt::AlignCenter);
        // create horizontal layout
        QHBoxLayout* pelayout=new QHBoxLayout;
        // and add label to it
        pelayout->addWidget(pelabel);
        QWidget* pewidget=new QWidget;
        // set layout to widget
        pewidget->setLayout(pelayout);
        pewidget->show();
    //MainWindow w;
    //w.show();
    return a.exec();
}

I created two "QLabel" in "Mainwindow.ui", but it opens two separate "Mainwindow.ui" and shows area and prime in each of them. But I want to have both on one "Mainwindow.ui".

[SGaist]

No, currently it shows two widgets: arwidget and pewidget.

MainWindow.ui is innocent here since you don't even show MainWindow.

If you only want to show one widget, create a QWidget, put a layout on it and add arwidget and pewidget to it. You don't even need MainWindow.

[Rela]

@SGaist
Hi, last week I created one widget and it worked. Today, I was goign to run it again, but the files format has changed. I think MSV was updated. First time MVS 2015 gave error "Severity Code Description Project File Line Suppression State Error Solution is not saved. Please save your solution before managing NuGet packages. 0".
Should I click on Restore NuGet Packages?

[SGaist]

I don't see why not.

Note that your link is pointing to an invalid page

[Rela]

@SGaist
The MVS 2015 was updated automatically and after that it and Qt are not working anymore.
First it gave error "...Please save your solution before managing NuGet packages". After that "the project file was unloaded". But when I tried other projects the error changed to "Failed to locate: "CL.exe. The system cannot find the file specified". I tried to install some components VS 2015: "Control Panel > Programs >Programs and Features > Microsoft Visual Studio > 'modify' > Visual C++ components and install", but it shows this window: here

[jsulm]

Did you try the first option in this window?

[Rela]

@jsulm
Yes, it worked and now MSVC 2015 is working, but not Qt. 5.5.
It gives error "Qt Creator needs a compiler set up to build. Configure a compiler in the kit options." in "Issues and in "Complie Output" the error "Configuration is faulty. Check the Issues view for details. Error while building/deploying project Circle2 (kit: Desktop Qt 5.5.1 MSVC2013 64bit) When executing step "Make". "

I installed "standalone SDK" from here here Downloaded and a folder "Windows kits" was built in the same folder. I copied it in "Visual studio 14" folder, and run the Qt again, but this is Build & Run. No active "Desktop Qt5.5. MCVS 2013 64 bit".

I dont know what the problem is? The kit should be MCVs 2105?

[SGaist]

I didn't realize… You changed Visual Studio's version in between. On Windows you can't mix and match compilers and libraries, Visual Studio's compilers are not compatible one with the other. So since you have the MSVC2013 Qt package, you have to use Visual Studio 2013 with it.

If you want to use Visual Studio 2015, you can either build Qt yourself, or go with the 5.6 beta which has VS2015 packages.

[Rela]

@SGaist said:
Thanks, which one do you recommend? I spent a lot of time on lunching and problem with running my programs until now because of components and compilers. If I uninstall 5.5 and install 6.5. beta, does Qt 6.5. work conveniently with Qt5.5. projects?