Processing XML data using the QDomDocument class is really simple:

1. Add the XML module to the project by opening the project (.pro) file and adding the xml text after core and gui, as shown in the following code:

QT += core gui xml

2. Create a user interface that carries a button that says Load XML:

3. Right-click on the button, choose Go to slot…, and select the clicked() option. Press the OK button and Qt will add a slot function to your source code.
4. Go to mainwindow.h and add the following headers so that we can make use of these classes:

#include <QDomDocument>
#include <QDebug>
#include <QFile>
#include <QFileDialog>

5. Go to mainwindow.cpp and insert the following code to the button's clicked() slot function:

void MainWindow::on_loadXmlButton_clicked() {
    QDomDocument xml;
    QString filename = QFileDialog::getOpenFileName(this, "Open Xml", ".", "Xml files (*.xml)");
    QFile file(filename);
    if (!file.open(QFile::ReadOnly | QFile::Text))
        qDebug() << "Error loading XML file.";
    if (!xml.setContent(&file)) {
        qDebug() << "Error setting content.";
        file.close();
        return;
    }
    file.close();

6. We continue to write the code to load XML:

QDomElement element = xml.documentElement();
    QDomNode node = element.firstChild();
    while(!node.isNull()) {
        QDomElement nodeElement = node.toElement();
        if(!nodeElement.isNull()) {
            if (nodeElement.tagName() == "object") {
                qDebug() << "[Object]=================================";
                QDomNode childNode = nodeElement.firstChild();

7. The previous code continues as follows:

                while (!childNode.isNull()) {
                    QDomElement childNodeElement = childNode.toElement();
                    QString name = childNodeElement.tagName();
                    if (name=="name" || name=="position" || name=="rotation" || name=="scale") {
                        QString text = childNodeElement.text();
                        qDebug() << name << text;
                    }
                    childNode = childNode.nextSibling();
                }
            }
            qDebug() << "=========================================";
        }
        node = node.nextSibling();
    }
}

8. Compile and run the program. Click on the Load XML button and select the XML file used in the first example. You should see the following output: