ground/gcs/src/shared/scriptwrapper/interface_wrap_helpers.h

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       interface_wrap_helpers.h
   5  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
   6  *             Parts by Nokia Corporation (qt-info@nokia.com) Copyright (C) 2009.
   7  * @brief
   8  * @see        The GNU Public License (GPL) Version 3
   9  * @defgroup
  10  * @{
  11  *
  12  *****************************************************************************/
  13 /*
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 3 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  21  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  22  * for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along
  25  * with this program; if not, write to the Free Software Foundation, Inc.,
  26  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  27  */
  28
  29 #ifndef INTERFACE_WRAP_HELPERS_H
  30 #define INTERFACE_WRAP_HELPERS_H
  31
  32 #include <QtScript/QScriptEngine>
  33
  34 namespace SharedTools {
  35 // Convert a QObjectInterface to Scriptvalue
  36 // To be registered as a magic creation function with qScriptRegisterMetaType().
  37 // (see registerQObjectInterface)
  38
  39 template <class QObjectInterface>
  40 static QScriptValue qObjectInterfaceToScriptValue(QScriptEngine *engine, QObjectInterface *const &qoif)
  41 {
  42     if (!qoif) {
  43         return QScriptValue(engine, QScriptValue::NullValue);
  44     }
  45
  46     QObject *qObject = const_cast<QObjectInterface *>(qoif);
  47
  48     const QScriptEngine::QObjectWrapOptions wrapOptions =
  49         QScriptEngine::ExcludeChildObjects | QScriptEngine::ExcludeSuperClassMethods | QScriptEngine::ExcludeSuperClassProperties;
  50     return engine->newQObject(qObject, QScriptEngine::QtOwnership, wrapOptions);
  51 }
  52
  53 // Convert  Scriptvalue back to  QObjectInterface
  54 // To be registered as a magic conversion function with  qScriptRegisterMetaType().
  55 // (see registerQObjectInterface)
  56
  57 template <class QObjectInterface>
  58 static void scriptValueToQObjectInterface(const QScriptValue &sv, QObjectInterface * &p)
  59 {
  60     QObject *qObject = sv.toQObject();
  61
  62     p = qobject_cast<QObjectInterface *>(qObject);
  63 }
  64
  65 // Magically register a Workbench interface derived from
  66 // ExtensionSystem::QObjectInterface class with the engine.
  67 // To avoid lifecycle issues, the script value is created on the QObject returned
  68 // by ExtensionSystem::QObjectInterface::qObject() and given the specified
  69 // prototype. By convention, ExtensionSystem::QObjectInterface::qObject() returns an
  70 // QObject that implements the interface, so it can be casted to it.
  71
  72 template <class QObjectInterface, class Prototype>
  73 static void registerQObjectInterface(QScriptEngine *engine)
  74 {
  75     Prototype *protoType = new Prototype(engine);
  76     const QScriptValue scriptProtoType = engine->newQObject(protoType);
  77
  78     const int metaTypeId = qScriptRegisterMetaType<QObjectInterface *>(
  79         engine,
  80         qObjectInterfaceToScriptValue<QObjectInterface>,
  81         scriptValueToQObjectInterface<QObjectInterface>,
  82         scriptProtoType);
  83
  84     Q_UNUSED(metaTypeId)
  85 }
  86 } // namespace SharedTools
  87
  88 #endif // INTERFACE_WRAP_HELPERS_H