setWindowIcon only works once?

Slei

Hey,

I'm currently trying to change th Window icon dynmically at run time, but it seems like using setWindowIcon only works once, afterwards it doesn't change anymore.
Is there a way to change it dynamically on windows?

thanks slei~

SGaist

Hi,

Please you show the code you are using for that.
Also:

What version of Qt are you using ?
On what platform ?

Slei

@SGaist
I'm using setWindowIcon(..)
m_application->setWindowIcon(icon);

the icon variable works for the systemtray icon, but doesn't work form setWindowIcon, so I'm passing the correct QIcon to the setWindowIcon function

SGaist

Are you using the same icon variable for setWindowIcon then for the system tray ?

You omitted to answer two questions.

Slei

@SGaist

The issues exists on Windows.

And yes it is the same QIcon variable, I've tried to manually change it with different QIcons but nothing happens

dheerendra

Can you show me how you are getting the object m_application ? Are you creating it ?

Slei

@dheerendra

I'm creating the object my self in an custom object which is created in the main.cpp:

``

MyApp.h
std::unique_ptr<QApplication> m_application;

MyApp.cpp
m_application = std::make_unique<QApplication>(argc,
argv);

dheerendra

show me your main.cpp ?

Slei

@dheerendra ```

int main(int argc, char *argv[])
{
MyApp a(argc, argv);
MainWindow w;
w.show();

//this just uses the QApplication exec
return a.exec();
}


In generall i'm actually using the MyApp just as it would be a QApplication directly nothing special,

dheerendra

MyApp is inherited from QApplication ?

Slei

@dheerendra
no it just has a QApplication member and has similar member functions(like exec)

MyApp.h
std::unique_ptr<QApplication> m_application;

dheerendra

My suspect was you have two different instances of QApplication and could be causing the issue. Looks like this is not issue.

I tried on Windows & Mac. It works without any issue. Can you try the following sample?

void MyWidget::on_pushButton_clicked()
{
qDebug() << Q_FUNC_INFO << endl;
qApp->setWindowIcon(QIcon(":/Phone_1.jpg"));
}

void MyWidget::on_pushButton_2_clicked()
{
qDebug() << Q_FUNC_INFO << endl;
qApp->setWindowIcon(QIcon(":/RightOption.png"));
}
==========main.cpp =========

QApplication a(argc, argv);
a.setWindowIcon(QIcon(":/Air.png"));
MyWidget w;
w.show();

Slei

@dheerendra
I'm using QML instead of QWidget for the gui app, might there be any issue?

dheerendra

Yes. it is issue with QML application. It is bug. It should work the same way. Issue is coming from application object. Instead of using the application object to change with window icon, we can use the top-level window object & use the setIcon(...) method to set it. It should work.

Slei

Ok Its working now, the issue was indeed QML, now I'Ve just the QQuickWindow as base class for my QML window and use its seticon function on each window instead of using the QApplication setWindowicon

dheerendra

That is good. You can move the issue to "Solved" state. Enjoy the Qt Programming.