QXmlSchema Class

This class is used to represent schemas that conform to the XML Schema 1.0 specification.

See also QXmlSchemaValidator, XML Schema Validation Example

Constructs an invalid, empty schema that cannot be used until load() is called.

Constructs a QXmlSchema that is a copy of other. The new instance will share resources with the existing schema to the extent possible.

Destroys this QXmlSchema.

Returns the document URI of the schema or an empty URI if no schema has been set.

Returns true if this schema is valid. Examples of invalid schemas are ones that contain syntax errors or that do not conform the W3C XML Schema specification.

Sets this QXmlSchema to a schema loaded from the source URI.

If the schema is invalid, false is returned and the behavior is undefined.

Example:

    QUrl url("http://www.schema-example.org/myschema.xsd");

    QXmlSchema schema;
    if (schema.load(url) == true)
        qDebug() << "schema is valid";
    else
        qDebug() << "schema is invalid";

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Sets this QXmlSchema to a schema read from the source device. The device must have been opened with at least QIODevice::ReadOnly.

documentUri represents the schema obtained from the source device. It is the base URI of the schema, that is used internally to resolve relative URIs that appear in the schema, and for message reporting.

If source is null or not readable, or if documentUri is not a valid URI, behavior is undefined.

If the schema is invalid, false is returned and the behavior is undefined.

Example:

    QFile file("myschema.xsd");
    file.open(QIODevice::ReadOnly);

    QXmlSchema schema;
    schema.load(&file, QUrl::fromLocalFile(file.fileName()));

    if (schema.isValid())
        qDebug() << "schema is valid";
    else
        qDebug() << "schema is invalid";

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Sets this QXmlSchema to a schema read from the data

documentUri represents the schema obtained from the data. It is the base URI of the schema, that is used internally to resolve relative URIs that appear in the schema, and for message reporting.

If documentUri is not a valid URI, behavior is undefined.

If the schema is invalid, false is returned and the behavior is undefined.

Example:

    QByteArray data( "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
                     "<xsd:schema"
                     "        xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\""
                     "        xmlns=\"http://www.qt-project.org/xmlschematest\""
                     "        targetNamespace=\"http://www.qt-project.org/xmlschematest\""
                     "        version=\"1.0\""
                     "        elementFormDefault=\"qualified\">"
                     "</xsd:schema>" );

    QXmlSchema schema;
    schema.load(data);

    if (schema.isValid())
        qDebug() << "schema is valid";
    else
        qDebug() << "schema is invalid";

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Returns the message handler that handles compile and validation messages for this QXmlSchema.

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Returns the name pool used by this QXmlSchema for constructing names. There is no setter for the name pool, because mixing name pools causes errors due to name confusion.

Returns the network manager, or 0 if it has not been set.

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Changes the message handler for this QXmlSchema to handler. The schema sends all compile and validation messages to this message handler. QXmlSchema does not take ownership of handler.

Normally, the default message handler is sufficient. It writes compile and validation messages to stderr. The default message handler includes color codes if stderr can render colors.

When QXmlSchema calls QAbstractMessageHandler::message(), the arguments are as follows:

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Sets the network manager to manager. QXmlSchema does not take ownership of manager.

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Sets the URI resolver to resolver. QXmlSchema does not take ownership of resolver.

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Returns the schema's URI resolver. If no URI resolver has been set, Qt XML Patterns will use the URIs in schemas as they are.

The URI resolver provides a level of abstraction, or polymorphic URIs. A resolver can rewrite logical URIs to physical ones, or it can translate obsolete or invalid URIs to valid ones.

When Qt XML Patterns calls QAbstractUriResolver::resolve() the absolute URI is the URI mandated by the schema specification, and the relative URI is the URI specified by the user.

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Copies the resources of other into this instance, sharing them to the extent possible.

This function was introduced in Qt 5.4.