QML / QWidget & Window icons

  • Moderators

    Hi everyone,

    I'm looking for the QML equivalent of QWidget::SetWindowIcon and I seem unable to find it in the docu:

    Theres the title property but, one for the icon seems to be missing.

    I can set an Icon by calling
    QApplication::setWindowIcon(); inside the main.cpp
    but, thats global and can't be changed, once exec() is called.

    My last Idea(untested so far) would be, to move from QQmlApplicationEngine to a QQuickView, because that one has a setIcon function, but I would rather not go the way over QWidgets.

  • Lifetime Qt Champion


    This interest mailing list thread might be of use.

    It looks like the Window type is missing some APIs.

  • Qt Champions 2018

    What I would do:

    Create an attached type for the window with an icon property, effectively calling QWindow::setIcon.
    Usage would be like this:

    ApplicationWindow {
        // ...
        WindowHelper.icon: "qrc:/windowIconFile" 
      // ...

    reference: http://doc.qt.io/qt-5/qtqml-cppintegration-definetypes.html#providing-attached-properties

  • Moderators

    Thanks @SGaist and @GrecKo for your input on this issue.

    I ended up following the tip I found in the mailing list conversation SGaist posted.

    A QML Window is a QQuickWindow which is a subclass of QWindow, so the method you would want to call is QWindow::setIcon(QIcon &). Maybe you can create a subclass of QQuickWindow in C++ ...

    this is also basicaly what GrecKo suggested, I think.

    The fix was surprisingly easy, and I'm surpised that this hasn't been added to the official release yet, the Mailinglist conversation was on Jan 29, 2013!

    the Custom QQuickWindow

    #ifndef QUICKWINDOW_H
    #define QUICKWINDOW_H
    #include <QQuickWindow>
    #include <QIcon>
    class QuickWindow : public QQuickWindow
        Q_PROPERTY(QString windowIcon READ windowIcon WRITE setWindowIcon NOTIFY windowIconChanged)
        explicit QuickWindow(QQuickWindow *parent = nullptr) : QQuickWindow(parent)  {}
        const inline QString &windowIcon(){return str;}
        inline void setWindowIcon(const QString &str){
             if(str != m_str){
                 m_str = str;
                 emit windowIconChanged();
        void windowIconChanged();
        QString m_str;
    #endif // QUICKWINDOW_H


    #include "quickwindow.h"
    int main(int argc, char *argv[]){
       qmlRegisterType<QuickWindow>("QuickWindow",1,0, "QuickWindow");
       QQmlApplicationEngine engine;


    import QuickWindow 1.0
        title: qsTr("MyApp")
        windowIcon: ":/Path/to/image.png"

    and done.

    Thanks for the help guys.

  • @J.Hilk said in QML / QWidget & Window icons:

    const inline QString &windowIcon(){return str;}

    Hi J.Hilk,

    I just wonder that your solution work..
    I got a "str was not declared in this scope for

    const inline QString &windowIcon(){return str;}

    May you can give your code a try with the recend Qt-Version and QtCreator 4.9.0?

    Kind regards,

    J-I W.

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  • Moderators

    hi @nightshift and welcome
    that must have been a copy and past error on my side, as windowIcon() should return the member variable m_str
    can't believe, I missed that x)

  • Qt Champions 2018

    This must be a typo. return m_str will work.

    Note that by using QQuickWindow as a base class, you will lose some of the functionnality of QML Window, and even more of ApplicationWindow.

    That's why I suggested using an attached object so that it could attach to any arbitrary window without having to subclass one.

  • @J.Hilk thanks you for the quick answer. :)
    It's just the simple things which break the biggest inventions.
    Thanks for the Note, if I'am a pure Newbie and currently stumbling around Qt and C++, I don't think it will make a big issue for me, losing some funcionality. :D

    Have all a nice day!

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