Add W3C XML Schema validation support

This was done by Tobias Koenig, as part of an internship at Trolltech/Qt
Software, started at Wed Oct 1 18:32:43 2008 +0200, and the last commit being
part of this commit dating Tue Feb 24 11:03:36 2009 +0100. This is work
consisting of about 650 commits squashed into one, where the first commit was
61b280386c1905a15690fdd917dcbc8eb09b6283, in the repository before Qt's history
cut.

1 files changed, 175 insertions, 0 deletions

diff --git a/examples/xmlpatterns/schema/mainwindow.cpp b/examples/xmlpatterns/schema/mainwindow.cpp
new file mode 100644
index 0000000..807a65b
--- /dev/null
+++ b/examples/xmlpatterns/schema/mainwindow.cpp
@@ -0,0 +1,175 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the $MODULE$ of the Qt Toolkit.
+**
+** $TROLLTECH_DUAL_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui>
+#include <QtXmlPatterns>
+
+#include "mainwindow.h"
+#include "xmlsyntaxhighlighter.h"
+
+class MessageHandler : public QAbstractMessageHandler
+{
+    public:
+        MessageHandler()
+            : QAbstractMessageHandler(0)
+        {
+        }
+
+        QString statusMessage() const
+        {
+            return m_description;
+        }
+
+        int line() const
+        {
+            return m_sourceLocation.line();
+        }
+
+        int column() const
+        {
+            return m_sourceLocation.column();
+        }
+
+    protected:
+        virtual void handleMessage(QtMsgType type, const QString &description, const QUrl &identifier, const QSourceLocation &sourceLocation)
+        {
+            Q_UNUSED(type);
+            Q_UNUSED(identifier);
+
+            m_messageType = type;
+            m_description = description;
+            m_sourceLocation = sourceLocation;
+        }
+
+    private:
+        QtMsgType m_messageType;
+        QString m_description;
+        QSourceLocation m_sourceLocation;
+};
+
+MainWindow::MainWindow()
+{
+    setupUi(this);
+
+    new XmlSyntaxHighlighter(schemaView->document());
+    new XmlSyntaxHighlighter(instanceEdit->document());
+
+    schemaSelection->addItem(tr("Contact Schema"));
+    schemaSelection->addItem(tr("Recipe Schema"));
+    schemaSelection->addItem(tr("Order Schema"));
+
+    instanceSelection->addItem(tr("Valid Contact Instance"));
+    instanceSelection->addItem(tr("Invalid Contact Instance"));
+
+    connect(schemaSelection, SIGNAL(currentIndexChanged(int)), SLOT(schemaSelected(int)));
+    connect(instanceSelection, SIGNAL(currentIndexChanged(int)), SLOT(instanceSelected(int)));
+    connect(validateButton, SIGNAL(clicked()), SLOT(validate()));
+    connect(instanceEdit, SIGNAL(textChanged()), SLOT(textChanged()));
+
+    validationStatus->setAlignment(Qt::AlignCenter | Qt::AlignVCenter);
+
+    schemaSelected(0);
+    instanceSelected(0);
+}
+
+void MainWindow::schemaSelected(int index)
+{
+    instanceSelection->clear();
+    if (index == 0) {
+        instanceSelection->addItem(tr("Valid Contact Instance"));
+        instanceSelection->addItem(tr("Invalid Contact Instance"));
+    } else if (index == 1) {
+        instanceSelection->addItem(tr("Valid Recipe Instance"));
+        instanceSelection->addItem(tr("Invalid Recipe Instance"));
+    } else if (index == 2) {
+        instanceSelection->addItem(tr("Valid Order Instance"));
+        instanceSelection->addItem(tr("Invalid Order Instance"));
+    }
+    textChanged();
+
+    QFile schemaFile(QString(":/schema_%1.xsd").arg(index));
+    schemaFile.open(QIODevice::ReadOnly);
+    const QString schemaText(QString::fromLatin1(schemaFile.readAll()));
+    schemaView->setPlainText(schemaText);
+
+    validate();
+}
+
+void MainWindow::instanceSelected(int index)
+{
+    QFile instanceFile(QString(":/instance_%1.xml").arg((2*schemaSelection->currentIndex()) + index));
+    instanceFile.open(QIODevice::ReadOnly);
+    const QString instanceText(QString::fromLatin1(instanceFile.readAll()));
+    instanceEdit->setPlainText(instanceText);
+
+    validate();
+}
+
+void MainWindow::validate()
+{
+    const QByteArray schemaData = schemaView->toPlainText().toLatin1();
+    const QByteArray instanceData = instanceEdit->toPlainText().toLatin1();
+
+    MessageHandler messageHandler;
+
+    QXmlSchema schema;
+    schema.setMessageHandler(&messageHandler);
+
+    schema.load(schemaData, QUrl("http://dummySchemaUrl/"));
+
+    bool errorOccurred = false;
+    if (!schema.isValid()) {
+        errorOccurred = true;
+    } else {
+        QXmlSchemaValidator validator(schema);
+        if (!validator.validate(instanceData, QUrl("http://dummyInstanceUrl")))
+            errorOccurred = true;
+    }
+
+    if (errorOccurred) {
+        validationStatus->setText(messageHandler.statusMessage());
+        moveCursor(messageHandler.line(), messageHandler.column());
+    } else {
+        validationStatus->setText(tr("validation successful"));
+    }
+
+    QString styleSheet = QString("QLabel {background: %1; padding: 3px}").arg(errorOccurred ? QColor(Qt::red).lighter(160).name() : QColor(Qt::green).lighter(160).name());
+    validationStatus->setStyleSheet(styleSheet);
+}
+
+void MainWindow::textChanged()
+{
+    instanceEdit->setExtraSelections(QList<QTextEdit::ExtraSelection>());
+}
+
+void MainWindow::moveCursor(int line, int column)
+{
+    instanceEdit->moveCursor(QTextCursor::Start);
+    for (int i = 1; i < line; ++i)
+        instanceEdit->moveCursor(QTextCursor::Down);
+
+    for (int i = 1; i < column; ++i)
+        instanceEdit->moveCursor(QTextCursor::Right);
+
+    QList<QTextEdit::ExtraSelection> extraSelections;
+    QTextEdit::ExtraSelection selection;
+
+    const QColor lineColor = QColor(Qt::red).lighter(160);
+    selection.format.setBackground(lineColor);
+    selection.format.setProperty(QTextFormat::FullWidthSelection, true);
+    selection.cursor = instanceEdit->textCursor();
+    selection.cursor.clearSelection();
+    extraSelections.append(selection);
+
+    instanceEdit->setExtraSelections(extraSelections);
+
+    instanceEdit->setFocus();
+}