File indexing completed on 2024-04-21 04:41:45

 /***************************************************************************
  *   Copyright (C) 2018 by Emmanuel Lepage Vallee                          *
  *   Author : Emmanuel Lepage Vallee <emmanuel.lepage@kde.org>             *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
  *   it under the terms of the GNU General Public License as published by  *
  *   the Free Software Foundation; either version 3 of the License, or     *
  *   (at your option) any later version.                                   *
  *                                                                         *
  *   This program is distributed in the hope that it will be useful,       *
  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  *   GNU General Public License for more details.                          *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  **************************************************************************/
 #ifndef KQUICKITEMVIEWS_CONTEXTADAPTERFACTORY_H
 #define KQUICKITEMVIEWS_CONTEXTADAPTERFACTORY_H
 
 // Qt
 #include <QtCore/QObject>
 class QAbstractItemModel;
 class QQmlContext;
 class QQuickItem;
 
 // LibStdC++
 #include <functional>
 
 // KQuickItemViews
 class ContextAdapterFactoryPrivate;
 class ContextExtension;
 class ContextAdapter;
 
 /**
  * This class manage the content of the AbstractItemAdapter::context().
  *
  * It dynamically compute the roles used by the delegate and optimize
  * the updates.
  *
  * This avoids calling setProperty on every single role and refresh them in
  * every single `emit dataChanged`.
  *
  * `applyRoles` can be re-implemented to either add more properties to the
  * context or to convert some roles into a format easier to consume from QML.
  */
 class Q_DECL_EXPORT ContextAdapterFactory
 {
     friend class ContextAdapter; // Public API
     friend class DynamicContext; // call finish()
 public:
     /**
      * This constructor has an optional template parameter to specify a
      * different class to be built by the factory. By default it builds a
      * plain ContextAdapter
      */
     template<typename T = ContextAdapter> explicit ContextAdapterFactory() :
         ContextAdapterFactory([](QQmlContext* c)->ContextAdapter*{return new T(c);}){}
 
     virtual ~ContextAdapterFactory();
 
     QAbstractItemModel *model() const;
     void setModel(QAbstractItemModel *m);
 
     /**
      * Add more properties to the context.
      *
      * This must be called from the view constructor. If called later, it will
      * Q_ASSERT.
      *
      * Implementations must subclass ContextExtension to use this.
      */
     void addContextExtension(ContextExtension* pg);
 
     QSet<QByteArray> usedRoles() const;
 
     /**
      * Create a context adapter.
      *
      * This can only be done after the last context extension is added.
      */
     ContextAdapter* createAdapter(QQmlContext *parentContext = nullptr) const;
 
     /**
      * Alternate version of createAdapter with the ability to create derivative
      * of the ContextAdapter.
      */
     template<typename T>
     T* createAdapter(QQmlContext *p = nullptr) const {
         return static_cast<T*>(createAdapter([](QQmlContext* c)->ContextAdapter*{return new T(c);}, p));
     }
 
 private:
     using FactoryFunctor = std::function<ContextAdapter*(QQmlContext*)>;
     ContextAdapterFactory(FactoryFunctor f);
     ContextAdapter* createAdapter(FactoryFunctor, QQmlContext*) const;
 
     ContextAdapterFactoryPrivate* d_ptr;
     Q_DECLARE_PRIVATE(ContextAdapterFactory);
 };
 
 #endif