QIcon not working when making an 'empty qmake project'

DragonautX

I was trying out this tutorial on Qt Creator 4.1.0. I made an 'Empty qmake project' (I assumed that was the same as 'Empty Qt Project' in the tutorial), and I was able to get a QApplication and QPushButton working, but I can't get a QIcon to show for the button. I made a 'resource.qrc' and added a 'web.png' to it, no prefix, and I expected something like 'QIcon(":/web.png")' to work. What's odd is that if I made a 'Qt Widgets Application' project, commented out '#include "mainwindow.h"', and tried the same thing, adding a 'resource.qrc' and 'web.png', then adding a QIcon to a QPushButton worked. The image was showing.
Is anyone able to get a QIcon to show after making an 'empty qmake project'? When I tried it, I was on Windows 8.1, and I used only the kit 'Desktop Qt 5.7.0 MSVC2015_64bit'. I thought since my .pro,main.cpp, and resource.qrc file were small, I 'd include them here.

/TEMPLATE = app
TARGET = name_of_the_app

QT = core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

SOURCES += \
    main.cpp

RESOURCES += \
    resource.qrc

#include <QApplication>
#include <QPushButton>

int main(int argc, char **argv)
{
 QApplication app (argc, argv);

 QPushButton button ("Hello world !");
 QIcon icon(":/web.png");\
 button.setIcon(icon);
 button.show();

 return app.exec();
}

<RCC>
    <qresource prefix="/">
        <file>web.png</file>
    </qresource>
</RCC>

mrjj

Hi
it looks ok syntax wise.
Did you run qmake after adding the qres?

Pradeep Kumar

Hi

@DragonautX

Welcome to the Qt Forum

I just tried the same thing Using Other Project->Empty qmake Project.
I am using Qt version 5.7, Windows OS 8.1.

In my .pro file

/TEMPLATE = app
TARGET = name_of_the_app

QT = core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

SOURCES +=
main.cpp

RESOURCES +=
otherfiles.qrc

main.cpp file

#include <QApplication>
#include <QPushButton>

int main(int argc, char **argv)
{
QApplication app (argc, argv);

QPushButton button;
QSize size(200,200);
QIcon icon(":/images.png");
button.setIcon(icon);
button.setIconSize(size);
button.show();


app.exec();

return app.exec();

}

I used QSize to increase the size of image in QPushbutton.
I added resource file , without prefix.

<RCC>
<qresource prefix="/">
<file>images.png</file>
</qresource>
</RCC>

I have attached the output.

https://postimg.org/image/c4n0n3795/

Can u delete pro.user file in folder,
clean the project, run qmake and build and run to see the result.

Thanks,

DragonautX

@mrjj Wow, that worked, thank you. Why does it work like that? When I was trying out this, I'd always do Ctrl + R to Run. Is running qmake different than clicking Run?

DragonautX

@Pradeep-Kumar I tried your idea after @mrjj , and that worked too. I'm realizing now there's three steps I can do, run qmake, build, and run. Do you know how is running qmake different from either building or running? I thought in c++ programs you first build and then run second, and then nothing more.

Pradeep Kumar

Hi,

qmake is required to generate project files, where the information provided in .pro files, later use build and run.

U can go through qmake tutoial

http://doc.qt.io/qt-4.8/qmake-manual.html

Thanks,

Pradeep Kumar

I hope ur question is solved , if so please mark your topic as solved , which will be useful in future to the users.

Cheers,
Thanks,