File indexing completed on 2024-04-28 15:32:02

 /*
     This file is part of the KDE libraries
     SPDX-FileCopyrightText: 2000 Carsten Pfeiffer <pfeiffer@kde.org>
     SPDX-FileCopyrightText: 2012 Kevin Ottens <ervin+bluesystems@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #ifndef KDRAGWIDGETDECORATOR_H
 #define KDRAGWIDGETDECORATOR_H
 
 #include <QObject>
 
 #include <kwidgetsaddons_export.h>
 
 #include <memory>
 
 class QDrag;
 
 /**
  * @brief A decorator which adds drag-support to widgets
  *
  * This is a decorator using an event filter to implement drag-support
  * in widgets.
  * You must override the virtual method dragObject() to specify the
  * QDrag to be used.
  *
  * @author Carsten Pfeiffer <pfeiffer@kde.org>
  */
 class KWIDGETSADDONS_EXPORT KDragWidgetDecoratorBase : public QObject
 {
     Q_OBJECT
     Q_PROPERTY(bool isDragEnabled READ isDragEnabled WRITE setDragEnabled)
 
 public:
     /**
      * Default constructor.
      */
     explicit KDragWidgetDecoratorBase(QWidget *parent = nullptr);
 
     /**
      * Destructs the decorator.
      */
     ~KDragWidgetDecoratorBase() override;
 
     /**
      * Enables/disables drag-support. Default is enabled.
      */
     void setDragEnabled(bool enable);
 
     /**
      * @returns if drag support is enabled or not.
      */
     bool isDragEnabled() const;
 
 protected:
     /**
      * @return the widget this decorator is attached to
      */
     QWidget *decoratedWidget() const;
 
     /**
      * Reimplement this and return the QDrag object that should be used
      * for the drag. Remember to give it "decoratedWidget()" as parent.
      *
      * Default implementation returns a null pointer, so that no drag is initiated.
      */
     virtual QDrag *dragObject();
 
     /**
      * Reimplemented to add drag-support
      */
     bool eventFilter(QObject *watched, QEvent *event) override;
 
     /**
      * Starts a drag (Copy by default) using dragObject()
      */
     virtual void startDrag();
 
 private:
     std::unique_ptr<class KDragWidgetDecoratorBasePrivate> const d;
 };
 
 /**
  * @class KDragWidgetDecorator kdragwidgetdecorator.h KDragWidgetDecorator
  *
  * @brief A decorator which adds drag-support to widgets
  *
  * This is a decorator using an event filter to implement drag-support
  * in widgets.
  * You must set the dragObjectFactory to specify the QDrag to be used.
  *
  * @author Kevin Ottens <ervin@kde.org>
  */
 template<class Widget>
 class KDragWidgetDecorator : public KDragWidgetDecoratorBase
 {
 public:
     typedef QDrag *(*DragObjectFactory)(Widget *);
 
     KDragWidgetDecorator(Widget *parent = nullptr)
         : KDragWidgetDecoratorBase(parent)
         , m_factory(nullptr)
     {
     }
 
     /**
      * @return the QDrag factory used by this decorator
      */
     DragObjectFactory dragObjectFactory() const
     {
         return m_factory;
     }
 
     /**
      * Set a factory to be used by this decorator
      *
      * @param factory the new QDrag factory to use
      */
     void setDragObjectFactory(DragObjectFactory factory)
     {
         m_factory = factory;
     }
 
 private:
     /**
      * Reimplemented to use the QDrag factory
      */
     QDrag *dragObject() override
     {
         if (m_factory) {
             Widget *w = static_cast<Widget *>(decoratedWidget());
             return m_factory(w);
         } else {
             return KDragWidgetDecoratorBase::dragObject();
         }
     }
 
     DragObjectFactory m_factory;
 };
 
 #endif // KDRAGWIDGETDECORATOR_H