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/*!
  \module QtQml
  \title Qt Declarative Module
  \ingroup modules

  \brief The Qt Declarative module provides a declarative framework
  for building highly dynamic, custom user interfaces.

  To include the definitions of the module's classes, use the
  following directive:

  \code
  #include <QtQml>
  \endcode

  To link against the module, add this line to your \l qmake \c
  .pro file:

  \code
  QT += declarative
  \endcode

  For more information on the Qt Declarative module, see the
  \l{Qt Quick} documentation.
*/


/*!
  \macro QML_DECLARE_TYPE()
  \relates QQmlEngine

  Equivalent to \c Q_DECLARE_METATYPE(TYPE *) and \c Q_DECLARE_METATYPE(QQmlListProperty<TYPE>)

  #include <QtQml> to use this macro.
*/

/*!
  \macro QML_DECLARE_TYPEINFO(Type,Flags)
  \relates QQmlEngine

  Declares additional properties of the given \a Type as described by the
  specified \a Flags.
  
  Current the only supported type info is \c QML_HAS_ATTACHED_PROPERTIES which
  declares that the \a Type supports \l {Attached Properties}.

  #include <QtQml> to use this macro.
*/


/*!
  \fn int qmlRegisterType(const char *uri, int versionMajor, int versionMinor, const char *qmlName)
  \relates QQmlEngine

  This template function registers the C++ type in the QML system with
  the name \a qmlName, in the library imported from \a uri having the
  version number composed from \a versionMajor and \a versionMinor.

  Returns the QML type id.

  There are two forms of this template function:

  \code
  template<typename T>
  int qmlRegisterType(const char *uri, int versionMajor, int versionMinor, const char *qmlName);

  template<typename T, int metaObjectRevision>
  int qmlRegisterType(const char *uri, int versionMajor, int versionMinor, const char *qmlName);
  \endcode

  The former is the standard form which registers the type \e T as a new type.
  The latter allows a particular revision of a class to be registered in
  a specified version (see \l {QML Type Versioning}).


  For example, this registers a C++ class \c MySliderItem as a QML type
  named \c Slider for version 1.0 of a \l{QML Modules}{module} called
  "com.mycompany.qmlcomponents":

  \code
  #include <QtQml>

  ...

  qmlRegisterType<MySliderItem>("com.mycompany.qmlcomponents", 1, 0, "Slider");
  \endcode

  Once this is registered, the type can be used in QML by importing the 
  specified module name and version number:

  \qml
  import com.mycompany.qmlcomponents 1.0

  Slider {
      // ...
  }
  \endqml

  Note that it's perfectly reasonable for a library to register types to older versions
  than the actual version of the library. Indeed, it is normal for the new library to allow
  QML written to previous versions to continue to work, even if more advanced versions of
  some of its types are available.
*/

/*!
  \fn int qmlRegisterRevision(const char *uri, int versionMajor, int versionMinor)
  \relates QQmlEngine

  This template function registers the specified revision of a C++ type in the QML system with
  the library imported from \a uri having the version number composed
  from \a versionMajor and \a versionMinor.

  Returns the QML type id.

  \code
  template<typename T, int metaObjectRevision>
  int qmlRegisterRevision(const char *uri, int versionMajor, int versionMinor);
  \endcode

  This function is typically used to register the revision of a base class to
  use for the specified module version (see \l {QML Type Versioning}).
*/

/*!
  \fn int qmlRegisterUncreatableType(const char *uri, int versionMajor, int versionMinor, const char *qmlName, const QString& message)
  \relates QQmlEngine

  This template function registers the C++ type in the QML system with
  the name \a qmlName, in the library imported from \a uri having the
  version number composed from \a versionMajor and \a versionMinor.

  While the type has a name and a type, it cannot be created, and the
  given error \a message will result if creation is attempted.

  This is useful where the type is only intended for providing attached properties or enum values.

  Returns the QML type id.

  #include <QtQml> to use this function.

  \sa qmlRegisterTypeNotAvailable()
*/

/*!
  \fn int qmlRegisterTypeNotAvailable(const char *uri, int versionMajor, int versionMinor, const char *qmlName, const QString& message)
  \relates QQmlEngine

  This function registers a type in the QML system with the name \a qmlName, in the library imported from \a uri having the
  version number composed from \a versionMajor and \a versionMinor, but any attempt to instantiate the type
  will produce the given error \a message.

  Normally, the types exported by a module should be fixed. However, if a C++ type is not available, you should
  at least "reserve" the QML type name, and give the user of your module a meaningful error message.

  Returns the QML type id.

  Example:

  \code
  #ifdef NO_GAMES_ALLOWED
  qmlRegisterTypeNotAvailable("MinehuntCore", 0, 1, "Game", "Get back to work, slacker!");
  #else
  qmlRegisterType<MinehuntGame>("MinehuntCore", 0, 1, "Game");
  #endif
  \endcode

  This will cause any QML which uses this module and attempts to use the type to produce an error message:
  \code
  fun.qml: Get back to work, slacker!
     Game {
     ^
  \endcode

  Without this, a generic "Game is not a type" message would be given.

  #include <QtQml> to use this function.

  \sa qmlRegisterUncreatableType()
*/

/*!
  \fn int qmlRegisterType()
  \relates QQmlEngine
  \overload

  This template function registers the C++ type in the QML
  system. Instances of this type cannot be created from the QML
  system.

  #include <QtQml> to use this function.

  Returns the QML type id.
*/

/*!
  \fn int qmlRegisterInterface(const char *typeName)
  \relates QQmlEngine

  This template function registers the C++ type in the QML system
  under the name \a typeName.

  #include <QtQml> to use this function.

  Returns the QML type id.
*/

/*!
   \fn int qmlRegisterModuleApi(const char *uri, int versionMajor, int versionMinor, QJSValue (*callback)(QQmlEngine *, QJSEngine *))
   \relates QQmlEngine

   This function may be used to register a module API provider \a callback in a particular \a uri
   with a version specified in \a versionMajor and \a versionMinor.

   Installing a module API into a uri allows developers to provide arbitrary functionality
   (methods and properties) in a namespace that doesn't necessarily contain elements.

   A module API may be either a QObject or a QJSValue.  Only one module API provider
   may be registered into any given namespace (combination of \a uri, \a versionMajor and \a versionMinor).
   This function should be used to register a module API provider function which returns a QJSValue as a module API.

   \b{NOTE:} QJSValue module API properties will \b{not} trigger binding re-evaluation if changed.

   Usage:
   \code
   // first, define the module API provider function (callback).
   static QJSValue *example_qjsvalue_module_api_provider(QQmlEngine *engine, QJSEngine *scriptEngine)
   {
       Q_UNUSED(engine)

       static int seedValue = 5;
       QJSValue example = scriptEngine->newObject();
       example.setProperty("someProperty", seedValue++);
       return example;
   }

   // second, register the module API provider with QML by calling this function in an initialization function.
   ...
   qmlRegisterModuleApi("Qt.example.qjsvalueApi", 1, 0, example_qjsvalue_module_api_provider);
   ...
   \endcode

   In order to use the registered module API in QML, you must import the module API.
   \qml
   import QtQuick 2.0
   import Qt.example.qjsvalueApi 1.0 as ExampleApi
   Item {
       id: root
       property int someValue: ExampleApi.someProperty
   }
   \endqml
  */

/*!
   \fn int qmlRegisterModuleApi(const char *uri, int versionMajor, int versionMinor, QObject *(*callback)(QQmlEngine *, QJSEngine *))
   \relates QQmlEngine

   This function may be used to register a module API provider \a callback in a particular \a uri
   with a version specified in \a versionMajor and \a versionMinor.

   Installing a module API into a uri allows developers to provide arbitrary functionality
   (methods and properties) in a namespace that doesn't necessarily contain elements.

   A module API may be either a QObject or a QJSValue.  Only one module API provider
   may be registered into any given namespace (combination of \a uri, \a versionMajor and \a versionMinor).
   This function should be used to register a module API provider function which returns a QObject as a module API.

   A QObject module API must be imported with a qualifier, and that qualifier may be used as
   the target in a \l Connections element or otherwise used as any other element id would.
   One exception to this is that a QObject module API property may not be aliased (because the
   module API qualifier does not identify an object within the same component as any other item).

   Usage:
   \code
   // first, define your QObject which provides the functionality.
   class ModuleApiExample : public QObject
   {
       Q_OBJECT
       Q_PROPERTY (int someProperty READ someProperty WRITE setSomeProperty NOTIFY somePropertyChanged)

   public:
       ModuleApiExample(QObject* parent = 0)
           : QObject(parent), m_someProperty(0)
       {
       }

       ~ModuleApiExample() {}

       Q_INVOKABLE int doSomething() { setSomeProperty(5); return m_someProperty; }

       int someProperty() const { return m_someProperty; }
       void setSomeProperty(int val) { m_someProperty = val; emit somePropertyChanged(val); }

   signals:
       void somePropertyChanged(int newValue);

   private:
       int m_someProperty;
   };

   // second, define the module API provider function (callback).
   static QObject *example_qobject_module_api_provider(QQmlEngine *engine, QJSEngine *scriptEngine)
   {
       Q_UNUSED(engine)
       Q_UNUSED(scriptEngine)

       ModuleApiExample *example = new ModuleApiExample();
       return example;
   }

   // third, register the module API provider with QML by calling this function in an initialization function.
   ...
   qmlRegisterModuleApi("Qt.example.qobjectApi", 1, 0, example_qobject_module_api_provider);
   ...
   \endcode

   In order to use the registered module API in QML, you must import the module API.
   \qml
   import QtQuick 2.0
   import Qt.example.qobjectApi 1.0 as ExampleApi
   Item {
       id: root
       property int someValue: ExampleApi.someProperty

       Component.onCompleted: {
           someValue = ExampleApi.doSomething()
       }
   }
   \endqml
  */