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Changing width and height

  • Hello,

    i just started learning QML and i have a really simple problem: i want to change the size of my main window with my cpp code and i just does not work :(

    Here is a little example:
    import QtQuick 2.0

    Rectangle {
    width: 360
    height: 360
    color: "white"

    Rectangle {
        x: 200
        y: 203
        width: 96
        height: 92
        color: "yellow"
        objectName: "objectName"


    #include <QtGui/QGuiApplication>
    #include "qtquick2applicationviewer.h"
    #include "qqmlengine.h"
    #include "qqmlcomponent.h"
    #include "qquickitem.h"

    int main(int argc, char *argv[])
    QGuiApplication app(argc, argv);

    QtQuick2ApplicationViewer viewer;
    QQuickItem *object = viewer.rootObject();
    QQuickItem *rect = object->findChild<QQuickItem*>("objectName");
    object->setProperty("width", 20);
    object->setProperty("height", 20);
    object->setProperty("color", "black");
    rect->setProperty("width", 10);
    rect->setProperty("height", 10);
    return app.exec();


    Those two lines just don't do anything:
    object->setProperty("width", 20);
    object->setProperty("height", 20);

    Changing the color of object works. Changing width and height of rect also works. The only thing that does not work is changing the size of object and i cant figure out why. Changing width and height in my QML code also works.

    Can anyone please tell me how i can change this size?? Thanks! :)

  • Hi, you can try changing the size of the QtQuick2ApplicationViewer itself instead of the root object:
    that might also change the size of the root object I think. Maybe try it yourself :)

  • Works! Thank you :)

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