.qmltypes not found by QtCreator for custom Qml Components

AlexanderF

I'm having trouble getting the qmldir and the qmlplugindump / .qmltypes infrastructure to work in my QtCreator with Qt 5.12.3

I have a folder QmlResources that builds a library of the same name (CMake based).
Inside it there is a /qml folder containing a CustomButton.qml and a qmldir. Both are added to a qml.qrc located in the main folder. There is also a /src folder containing a class based on QQmlExtensionPlugin, so the result is

/QmlResources
        CMakeLists.txt
        qml.qrc
    /qml/
        CustomButton.qml
        qmldir
    /src/
        QmlResources.h

The qml.qrc looks like this

<RCC>
    <qresource prefix="/QmlResources">
        <file>qml/CustomButton.qml</file>
        <file>qml/qmldir</file>
    </qresource>
</RCC>

qmldir:

module QmlResources
CustomButton 0.1 CustomButton.qml
plugin QmlResources

CustomButton.qml

import QtQuick 2.6
import QtQuick.Controls 1.4
Button {
    // some button stuff
}

QmlResources.h

class CustomQmlResources final: public QQmlExtensionPlugin {
    Q_OBJECT
    Q_PLUGIN_METADATA(IID "somestring")

public:
    CustomQmlResources ();
    void registerTypes(const char * uri) override {
        qmlRegisterType(QUrl("qrc:/QmlResources/qml/CustomButton.qml"), uri, MAJOR, MINOR, "CustomButton");
    };
};

Now QtCreator is telling me when I import QmlResources 0.1 in a QML file:
"QML module does not contain information about components contained in plugins"

When I try to run "qmlplugindump.exe QmlResources 0.1" in the qml folder I get

QQmlComponent: Component is not ready
file:///typelist.qml:3:1: module "QmlResources" is not installed

I've read all of the documentation about qmldirs and plugins multiple times and I can't figure out how this is supposed to work

AlexanderF

I made some progress and I was able to generate a .qmltypes file.
Some issues I had to fix:

qml.qrc needed to be in the same folder as the qmls and qmldir so the path doesn't need /qml/
The registerType has to use the now shorter url, eg qmlRegisterType(QUrl("qrc:/QmlResources/CustomButton.qml"), uri, MAJOR, MINOR, "CustomButton");
With the cxx plugin it seems to be unnecessary adding the CustomButton to the qmldir. What needs to be there is "module QmlResources" and "plugin QmlResources"
The qmlplugindump.exe needs to be run inside the release folder with the release.dlls, otherwise it won't find required dependencies, eg "/loaddependencies.qml:2:1: module "QtQuick" plugin "qtquick2plugin" not found"

After generating the .qmltypes file I added it to the /qml/ folder and put this in the qmldir "typeinfo qmlresources.qmltypes". Unfortunately it's still trying to auto generate and failing due to the QtQuick dependency it fails to find.

AlexanderF

I got it to work! What was missing was installing the .qmltypes file into the build folder of QmlResources together with the qmldir, so both can be found by the QtCreator