QML Image disply without window

sandro4912

Ok Im new to qml and I found this example code to run:

import QtQuick 2.12

Image {
    id: root
    source: "images/background.png"
}

However If I run this nothing shows up.

I created an empty Qt Quick app with creator and it looks like it needs a window.

So this worked well:

import QtQuick 2.14
import QtQuick.Window 2.14

Window {
    visible: true
    width: 640
    height: 480

    Image {
        id: root
        source: "images/background.png"
    }
}

So short stupid question. Can Image get displayed without the window?

eyllanesc

How do you execute that code?

sandro4912

I just made a empty Qt Quick project and hit build and run in debug.

I think the qml gets run with its coresponding main.cpp

#include <QGuiApplication>
#include <QQmlApplicationEngine>

int main(int argc, char *argv[])
{
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);

    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    const QUrl url(QStringLiteral("qrc:/main.qml"));
    QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
                     &app, [url](QObject *obj, const QUrl &objUrl) {
        if (!obj && url == objUrl)
            QCoreApplication::exit(-1);
    }, Qt::QueuedConnection);
    engine.load(url);

    return app.exec();
}

Markkyboy

This post is deleted!

sandro4912

@sandro4912 said in QML Image disply without window:

import QtQuick 2.12

Image {
id: root
source: "images/background.png"
}

That was not the question.

The Question is. Can this work without window like this:

import QtQuick 2.12

Image {
    id: root
    source: "images/background.png"
}

J.Hilk

@sandro4912
AFAIK QQmlApplicationEngine needs a Window or similar top level QML component

if you use a QQuickWidget / QQuickView you may get away with an Item/Image as root element

sandro4912

@J-Hilk said in QML Image disply without window:

QQuickWidget

I modified my main to this:

#include <QApplication>
#include <QQuickWidget>

int main(int argc, char *argv[])
{
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);

    QApplication app(argc, argv);

    auto view = new QQuickWidget;
    view->setSource(QStringLiteral("qrc:/main.qml"));
    view->show();

    return app.exec();
}

Now I wonder whats the difference between QQuickWidget and QQmlApplicationEngine. Why not do everything with the QQuickWidget?

SGaist

Hi,

Because you might want to only use QML. QQuickWidget adds the widget module as dependency which might not be what you want.