Build and run simple QML on Webassembly

AlsaniePss

Hello everyone.
I am trying to run a simple QML on the web browser. Next some info:
Qt version: 5.14 (build from source wasm-emscripten)
emsdk version: 1.38.27

The simple QML build successfully. However, when I try to run it:

$ emrun *.html

I am getting the following error on the broswer: (I am not sure how to attach my files to this thread)

Qt for WebAssembly: myQML01
Application exit (TypeError: eventHandler.target is null)

AlsaniePss

I am not sure how to attach a file, but next is the source:
[pro file]

QT += quick
CONFIG += c++11
DEFINES += QT_DEPRECATED_WARNINGS
SOURCES += \
        main.cpp

RESOURCES += qml.qrc
QML_IMPORT_PATH =
QML_DESIGNER_IMPORT_PATH =
# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

[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();
}

[main.qml]

import QtQuick 2.13
import QtQuick.Window 2.13

Window
{
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello Webassembly")

    Rectangle
    {
        width: parent.width / 4
        height: parent.height / 4
        anchors.centerIn: parent
        color: "lightblue"
    }
}

lorn.potter

Unfortunately, we mistakenly applied a change to 5.14 that should not have been. It's revert is currently in the 5.14.2 branch as 3a6d8df5219653b043bd642668cee193f563ec84

https://codereview.qt-project.org/c/qt/qtbase/+/295372

AlsaniePss

@lorn-potter Thanks for the update! does the 5.14.2 still works with emsdk 1.38.27? do you know if it can work with a newer version of the emsdk?

lorn.potter

It will work with emsdk 1.38.27, and most likely up to 1.38.x series, but not the 1.39.x series.

AlsaniePss

@lorn-potter Great, thank you!
I will build 5.14.2 with emsdk 1.38.27 and see how it goes :)

AlsaniePss

@lorn-potter It's working... Woohoo, thanks! Now it builds. I just built simple QML :)