Unknown module(s) in QT: webenginewidgets

JacobNovitsky

How to fix below?
:-1: error: Unknown module(s) in QT: webenginewidgets



TEMPLATE = app
TARGET = QtGcppBrowser

# Enable C++17 in qmake
CONFIG += c++17

# Required Qt modules
QT += widgets webenginewidgets

SOURCES += main.cpp

# If building with very old qmake that lacks 'c++17', uncomment:
# CONFIG -= c++17
# CONFIG += c++1z

#include <QApplication>
#include <QWebEngineView>
#include <QUrl>

int main(int argc, char* argv[]) {
    QCoreApplication::setOrganizationName("QtExamples");
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
    QApplication app(argc, argv);

    QWebEngineView view;
    const QUrl start = QUrl::fromUserInput(argc > 1 ? argv[22] : "https://www.qt.io");
    view.setUrl(start);
    view.resize(1024, 750);
    view.show();
    return app.exec();
}

Christian Ehrlicher

You should install webengine through the Qt online installer. What Os and compiler do you use?

JacobNovitsky

Ubuntu
G++
I've built it from source

Christian Ehrlicher

So your built from source did not build QtWebEngine I would guess - make sure you installed all dependencies. The configure output will show you what is missing and what will be built.

JacobNovitsky

Can I add QtWebEngine avoiding Qt components full reinstall?

Christian Ehrlicher

You can select single components in the Qt online installer.

JacobNovitsky

How should I proceed? I have another machine with Qt installed with online installer

SGaist

Hi,

Since you already installed Qt using the online installer, go to the folder and use the Maintenance Tool to modify your installation.

JacobNovitsky

it does not work
Cannot initialize cache: Cannot obtain the lock for file "/home/j/.cache/qt-unified-linux-online/cache.lock": Resource temporarily unavailable

ChrisW67

As @Christian-Ehrlicher pointed out: if you built your Qt instance from source, then you need to reconfigure it to include the Web Engine components, rebuild, and reinstall.
If, as @SGaist has assumed, you installed your entire Qt from the online installer, then you need to run the Maintenance Tool, select the missing component(s), and let it install them for you.

The error message you posted seems to indicate that you are trying to install Qt using the online installer on top of an existing self-built Qt. You cannot add a component to an existing self-built Qt using the Qt Online installer. To install a completely new Qt instance you need to install into a fresh directory.

jsulm

@JacobNovitsky said in Unknown module(s) in QT: webenginewidgets:

Cannot obtain the lock for file "/home/j/.cache/qt-unified-linux-online/cache.lock": Resource temporarily unavailable

Is Qt Online Installer still running? If so close it and try again.
If it does not help delete that file manually.

JacobNovitsky

I've removed all components with Maintenance tool, then reinstalled
Qt and Web engine with online installer

Trying to compile sample project:

QT += widgets webenginewidgets
CONFIG += c++17
SOURCES += main.cpp

#include <QApplication>
#include <QWebEngineView>
#include <QUrl>

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

    QWebEngineView view;
    view.resize(1200, 800);
    view.load(QUrl(QStringLiteral("https://www.qt.io")));
    view.show();

    return app.exec();
}

getting error:
:-1: error: Unknown module(s) in QT: webchannel positioning

Kindly advise!
q.png

jsulm

@JacobNovitsky said in Unknown module(s) in QT: webenginewidgets:

webchannel positioning

Same: did you install these two modules?

JacobNovitsky

libqt6webchannel6/jammy,now 6.2.4-1ubuntu1 amd64 [installed,automatic]
libqt6webchannel6-dev/jammy,now 6.2.4-1ubuntu1 amd64 [installed,automatic]
1wlibqt6positioning6/jammy,now 6.2.4-1 amd64 [installed,automatic]
libqt6positioning6-plugins/jammy,now 6.2.4-1 amd64 [installed,automatic]
libqt6positioningquick6/jammy,now 6.2.4-1 amd64 [installed,automatic]
qt6-positioning-dev/jammy,now 6.2.4-1 amd64 [installed,automatic]

SGaist

@JacobNovitsky If you are using the Qt version from the online installer, you have to add these dependencies from the online installer as well...

Or just use the Qt version from your distribution. However you cannot mix and match.

JacobNovitsky

Should I install above libraries with version 6.9.2? (as per my Qt version)

jsulm

@JacobNovitsky You should install these libraries for the Qt version you're using.
You wrote:
"I've removed all components with Maintenance tool, then reinstalled
Qt and Web engine with online installer"
Doesn't that mean that you now need to install these modules using Qt Maintenance Tool from that Qt installation?

AsifBahrainwala

This post is deleted!

JacobNovitsky

All modules installed, version of module is the same as Qt -> 6.9.2
getting error when trying to build below:

:-1: error: Project ERROR: Unknown module(s) in QT: webchannel positioning

TEMPLATE = app
TARGET = webengine_test
QT += core gui widgets webenginewidgets   # <-- webenginewidgets is required

CONFIG += c++17

SOURCES += main.cpp

#include <QApplication>
#include <QWebEngineView>

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

    QWebEngineView view;
    view.resize(800, 600);
    view.load(QUrl("https://www.qt.io")); // any test URL
    view.show();

    return app.exec();
}

hskoglund