Deploy Qt5 QML application - qt

Question

To test QML deployment I've created a very simple QML application. Here is the code:
main.cpp
#include <QApplication>
#include <QQmlApplicationEngine>
#include <QFile>
int main(int argc, char **argv) {
QApplication app(argc, argv);
QQmlApplicationEngine engine;
QString path = app.applicationDirPath() + "/qml/main.qml";
if(QFile::exists(path))
engine.load(path);
else {
return 1;
}
return app.exec();
}
main.qml
import QtQuick 2.2
import QtQuick.Controls 1.2
ApplicationWindow {
id: mainWindow
title: "Test window"
width: 800
height: 600
visible: true
}
To be sure no development library was installed in the system, I've set up a virtual machine with a pure Windows XP installation. Then, I've followed instructions as described here and copied all Qt5*.dll into the program directory, as well as platforms/qwindows.dll and icu*52.dll. Dependency Walker confirmed that no broken dependencies were left, i.e. everything should have been correctly set up.
However, for some reasons, when I run my app I see nothing. Neither a window, nor an error message. Running from console also gives me no error. Despite this, I can see my app running in the Task manager, like it is running in background. Running the app on the development machine goes without problem: the app correctly starts and I can see its windows.
What am I doing wrong? How can I deploy a QML app to be sure it will work on any other - non development - machine?

Answer 1

If you use MinGW, then try to copy all folders from folders qml and plugins to directory with your program. Also copy libraries: icudt52.dll, icuin52.dll, icuuc52.dll, libgcc_s_dw2-1.dll, libstdc++-6.dll, libwinpthread-1.dll, Qt5Core.dll, Qt5Gui.dll, Qt5Network.dll, Qt5Qml.dll, Qt5Quick.dll, Qt5Svg.dll, Qt5Widgets.dll from bin
Eventually the directory will look like this:
Enginio
imageformats
platforms
Qt
QtGraphicalEffects
QtPositioning
QtQml
QtQuick
QtQuick.2
QtSensors
QtWebKit
QtWinExtras
icudt52.dll
icuin52.dll
icuuc52.dll
libgcc_s_dw2-1.dll
libstdc++-6.dll
libwinpthread-1.dll
Qt5Core.dll
Qt5Gui.dll
Qt5Network.dll
Qt5Qml.dll
Qt5Quick.dll
Qt5Svg.dll
Qt5Widgets.dll
YOUR_PROGRAM.exe
This way works on WindowsXP/Win7 where Qt was not installed.

Answer 2

This what i've figured out so far,
You can't just open a qml file in main.cpp, you have to put those qmls into a resource
qml.qrc:
<RCC>
<qresource prefix="/">
<file>main.qml</file>
</qresource>
</RCC>
Then main.cpp must load it from the resource
int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);
QQmlApplicationEngine engine;
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
return app.exec();
}
then build and check it works, then deploy as follows:
locate the releasse directory where your EXE lives
locate the directory where your QML lives
create a directory somewhere, say, deploy
then
cd deploy
windeployqt --release --qmldir <qml-dir-location> <exe-location>
NOTE: add location of windeployqt to PATH
eg. C:\Qt\Qt5.5.1\5.5\msvc2013\bin

Answer 3

You should use the deployment tool that comes with Qt. See Qt for Windows - Deployment, there is a section "the Windows deployment tool".

Answer 4

As mentioned by BaCaRoZzo, a general solution that worked pretty well for me is to follow this guide.
To sum it up, copy in an empty directory:
The release version of MyApp.exe, along with .dll you created for this projet
All the .dll files from \mingw48_32\bin\
All the folders from \mingw48_32\plugins\
(If you used QML) All the folders from \mingw48_32\qml\
First, during the test of your application, rename your qt folder so it is not found by $PATH, and double-click on MyApp.exe. This should run the program.
NB: It leads to a very big application, so you will need to delete some extra files and folders.
The easiest way is for the dll: you run the program, and while being run, you delete all the dll in your new project. Only the ones that are not used by MyApp.exe will be deleted. Efficient!
For the Qt folders, proceed by trials and errors.

Answer 5

You need to deploy the application, for this purpose I use the utility
cqtdeployer
This utility itself collects all the necessary dependencies of your application and you do not have to spend your time on it, or you can automate this process.
You can install from github releases (Windows)
or
from snapstore (Linux)
sudo snap install cqtdeployer
You can use as follows:
Windows:
%cqtdeployer% -bin myApp -qmake path/to/Qt/5.x.x/build/bin/qmake.exe -qmlDir path/to/my/qml/files/dir
Linux:
cqtdeployer -bin myApp -qmake path/to/Qt/5.x.x/build/bin/qmake -qmlDir path/to/my/qml/files/dir
path/to/Qt/5.x.x/build/bin/qmake - This is the way qmake is used to build your program.
path/to/my/qml/files/dir - this is the path directly to your qml file (which you wrote)
And Run application with sh script (Linux) or exe (Windows)
If you'll use the version from snap then make sure that you have all the permissions.
If you need use windows version just install application from installer

Answer 6

use windeployqt --qmldir f:\myApp\sources f:\build-myApp\myApp.exe command.
the first argument after qmldir is your qml folder location and the second argument is where your exe is placed. You would get deployable exe on any env.

Answer 7

For me this answer worked for a QtQuick 2 application (QML app), but I'm adding more details:
Build inside Qt as Release
Find the folder in the file explorer with the executable, usually on a sibling folder to your project folder
Copy executable to an empty folder
Start Qt CMD tool (mine is ), go to the folder with the executable and run:
windeployqt --release --qmldir C:\Qt\5.15.1\msvc2015_64\qml executable.exe
(change 5.15.1\msvc2015_64 for yours)

Answer 8

My answer was:
(1) On Qt Framework set the Release mode for my Application.
(2) After: Project -> Build directory and set a empty directory in the "C:/" folder (I'm development Windows 10). Example: My Folder: "Release" with subfolder "My_app", so the Build directory is "C:/Release/My_app"
(3) Click on "Start debuggin of the startup project"
(4) Create another folder on "C:/" directory (in my case callet "Executable" with subfolder "My_app").
(5) Copy "My_app.exe" of the folder "Release/My_app/release" to "C:/Executable/My_app").
(6) Open Qt mingw.
(7) On the terminal of the Qt MinGw go to folder "Release/My_app/release" through command "cd C:/Executable/My_app"
(8) Run the command "windeploy.exe My_app.exe --qmldir 'full_path_where_are_the_qml_files'" (e.g.: "C:/My_prj/qmlsource", where qmlsource is folder with my qml_files).
This generate all files to run My_app.exe. Just the copy all folder (My_prj folder).