kwin/libkdecorations/kdecorationfactory.h

/*****************************************************************
This file is part of the KDE project.

Copyright (C) 2003 Lubos Lunak <l.lunak@kde.org>

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******************************************************************/

#ifndef KDECORATIONFACTORY_H
#define KDECORATIONFACTORY_H

#include "kdecoration.h"

/** @addtogroup kdecoration */
/** @{ */

class KDecoration;
class KDecorationBridge;
class KDecorationFactoryPrivate;

class KWIN_EXPORT KDecorationFactory
    : public KDecorationDefines
{
public:
    /**
     * Constructor. Called after loading the decoration plugin. All global
     * initialization of the plugin should be done in the factory constructor.
     */
    KDecorationFactory();
    /**
     * Destructor. Called before unloading the decoration plugin. All global
     * cleanup of the plugin should be done in the factory destructor.
     */
    virtual ~KDecorationFactory();
    /**
     * This function must be reimplemented to create decoration objects.
     * The argument should be passed to the KDecoration constructor, the second
     * KDecoration argument should be this factory object.
     */
    virtual KDecoration* createDecoration(KDecorationBridge* bridge) = 0;
    /**
     * This function is called when the configuration settings changed.
     * The argument specifies what has changed, using the SettingXXX masks.
     * It should be determined whether the decorations need to be completely
     * remade, in which case true should be returned, or whether only e.g.
     * a repaint will be sufficient, in which case false should be returned,
     * and resetDecorations() can be called to reset all decoration objects.
     * Note that true should be returned only when really necessary.
     */
    virtual bool reset(unsigned long changed);   // returns true if the decoration needs to be recreated

    /**
     * Reimplement this function if your decoration supports more border sizes than
     * the default one (BorderNormal). The returned list must contain all supported
     * sizes, ordered from the smallest to the largest one. By default, only
     * BorderNormal is returned.
     */
    virtual QList< BorderSize > borderSizes() const;

    virtual bool supports(Ability ability) const = 0;

    virtual void checkRequirements(KDecorationProvides* provides);
    /**
     * Returns the KDecorationOptions object, which is used to access
     * configuration settings for the decoration.
     */
    const KDecorationOptions* options(); // convenience
    /**
     * Returns true if the given decoration object still exists. This is necessary
     * e.g. when calling KDecoration::showWindowMenu(), which may cause the decoration
     * to be destroyed. Note that this function is reliable only if called immediately
     * after such actions.
     */
    bool exists(const KDecoration* deco) const;

    /**
     * Set & get the position of the close button - most decorations don't have to call this ever.
     *
     * By default, the legacy position indicated by the options (top left or top right) will be
     * returned.
     * Only if you need to provide a bottom corner or your decoration does not respect those
     * settings you will have to specify the exact corner (eg. used by the "present windows"
     * closer)
     *
     * @since 4.8
     */
    Qt::Corner closeButtonCorner();
    void setCloseButtonCorner(Qt::Corner cnr);

    /**
     * @internal
     */
    void addDecoration(KDecoration*);
    /**
     * @internal
     */
    void removeDecoration(KDecoration*);
protected:
    /**
     * Convenience function that calls KDecoration::reset() for all decoration
     * objects.
     */
    void resetDecorations(unsigned long changed);   // convenience
    /**
     * This function has the same functionality like KDecoration::windowType().
     * It can be used in createDecoration() to return different KDecoration
     * inherited classes depending on the window type, as at that time
     * KDecoration::windowType() is not available yet. The additional argument
     * is the one passed to createDecoration().
     */
    NET::WindowType windowType(unsigned long supported_types, KDecorationBridge* bridge) const;
private:
    QList< KDecoration* > _decorations;
    KDecorationFactoryPrivate* d;
};

inline const KDecorationOptions* KDecorationFactory::options()
{
    return KDecoration::options();
}

/** @} */

#endif