QXmlSchema failing to validate and giving odd console output

Question

Edit I have added a minumum working code sample that produces the same errors at the bottom...

I have an xsd schema file and an xml file, both of which I have validated online, and I have used online tools to validate the xml file using my xsd schema. Everything is valid and compatible. I am now trying to use QXmlSchemaValidator to validate the same xml, using the same xsd, however, when I call:

if (!validator.validate(file.fileName()))

it returns false.

Here is the code snippet in which this happens:

LoadInfo JobTreeControl::loadXML_schemaValidation(QFile& file, QXmlStreamReader& iXml)
{
    QString schemeFilePath = QCoreApplication::applicationDirPath() + "/schema.xsd";
    QFile schemaFile(schemeFilePath);

    if (!schemaFile.open(QFile::ReadOnly | QFile::Text))
        return LoadInfo(false, "Schema file failed to open");

    QXmlSchema schema;

    if (!schema.load( QUrl::fromLocalFile(schemeFilePath)))
        return LoadInfo(false, "Qt schema failed to load schema file");

    if (!schema.isValid())
        return LoadInfo(false, "Schema is invalid");

    QXmlSchemaValidator validator(schema);

    if (!validator.validate(file.fileName()))
        return LoadInfo(false, "Load file is not a valid Pointfuse Batch Utility XML file");

    return LoadInfo(true);
}

I also get some interesting console output from the schema and validator:

QObject::connect: Cannot connect (null)::aboutToQuit() to QNativeWifiEngine::closeHandle() QEventLoop: Cannot be used without QApplication QEventLoop: Cannot be used without QApplication Error FODC0002 in c:/test Data/serializeArchive/test_newSaveFormat.xml, at line 1, column 0: Premature end of document.

I have tried googling these errors and QXmlSchema issues, and I'm not having much luck turning up anything. I did find this post which is close:

QEventLoop: Cannot be used without QApplication

...but his issue was that he didn't have an instance of QApplication running and therefor no event loop. I can tell you for certain that I do, as this code snippet is very deep inside my application, and is accessed when clicking on a QAction and having a QDialog pop up.

Below I'll write out which lines of code cause which console outputs:

QXmlSchema schema;

QObject::connect: Cannot connect (null)::aboutToQuit() to QNativeWifiEngine::closeHandle()

    if (!schema.load( QUrl::fromLocalFile(schemeFilePath)))

QEventLoop: Cannot be used without QApplication

    if (!validator.validate(file.fileName()))

QEventLoop: Cannot be used without QApplication Error FODC0002 in c:/test Data/serializeArchive/test_newSaveFormat.xml, at line 1, column 0: Premature end of document.

Thanks in advance for any help you can give,

Pete

Edit:

I can also confirm that both the xml filepath use to load QFile file, and the schemaFilePath used to load QFile schemaFile, are correct. Though this is confirmed when I successfully open and load each of these files.

Edit

And I'm curious to know why on earth my QXmlSchema is calling functions relating to QNativeWifiEngine... What does that have to do with the schema?

Edit With Minimum Working Example Code

I have written the shortest working example I can think of.

Bellow is the c++/Qt source:

class XmlValidator : public QDialog
{

public:

    XmlValidator()
        : QDialog()
    {
        QVBoxLayout* p_vBoxLayout = new QVBoxLayout;
        QPushButton* p_pushButton = new QPushButton("Validate XML");

        p_vBoxLayout->addWidget(p_pushButton);
        this->setLayout(p_vBoxLayout);

        connect(p_pushButton, &QPushButton::clicked, this, &XmlValidator::validateXML);
    }

    void validateXML(); 
};

void XmlValidator::validateXML()
{
    QString xmlFilePath = QCoreApplication::applicationDirPath() + "/testXml.xml";
    QString schemeFilePath = QCoreApplication::applicationDirPath() + "/testSchema.xsd";

    QFile xmlFile(xmlFilePath);
    QFile schemaFile(schemeFilePath);

    if (!xmlFile.open(QFile::ReadOnly | QFile::Text))
    {
        std::cout << "Xml file failed to open" << std::endl;
        return;
    }

    if (!schemaFile.open(QFile::ReadOnly | QFile::Text))
    {
        std::cout << "Schema file failed to open" << std::endl;
        return;
    }

    QXmlSchema schema;

    if (!schema.load(QUrl::fromLocalFile(schemeFilePath)))
    {
        std::cout << "Qt schema failed to load schema file" << std::endl;
        return;
    }

    if (!schema.isValid())
    {
        std::cout << "Schema is invalid" << std::endl;
        return;
    }

    QXmlSchemaValidator validator(schema);

    if (!validator.validate(xmlFilePath))
    {
        std::cout << "Xml file is not a valid" << std::endl;
        return;
    }
}

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    XmlValidator dialog;

    dialog.show();

    return a.exec();
}

Then testXml.xml

<?xml version="1.0" encoding="UTF-8"?>
<testSchemaElement version="4.5"/>

And finally testSchema.xsd

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:element name="testSchemaElement">
    <xs:complexType>
        <xs:attribute name="version" type="xs:decimal"/>
    </xs:complexType>
</xs:element>

</xs:schema>

The c++ application will look for these two files in it's working directory.