/* * Copyright 2006-2007 by Aaron Seigo * Copyright 2007 by Riccardo Iaconelli * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Library General Public License as * published by the Free Software Foundation; either version 2, 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 Library General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef PLASMA_APPLET_H #define PLASMA_APPLET_H #include #include #include #include #include #include #include #include namespace Plasma { class Containment; class DataEngine; class Package; /** * @short The base Applet class * * Applet provides several important roles for add-ons widgets in Plasma. * * First, it is the base class for the plugin system and therefore is the * interface to applets for host applications. It also handles the life time * management of data engines (e.g. all data engines accessed via * Applet::datEngine(const QString&) are properly deref'd on Applet * destruction), background painting (allowing for consistent and complex * look and feel in just one line of code for applets), loading and starting * of scripting support for each applet, providing access to the associated * plasmoid package (if any) and access to configuration data. * * See techbase.kde.org for tutorial on writing Applets using this class. */ class PLASMA_EXPORT Applet : public Widget { Q_OBJECT // Q_PROPERTY( QRectF maxSizeHint READ maxSizeHint ) Q_PROPERTY( bool hasConfigurationInterface READ hasConfigurationInterface WRITE setHasConfigurationInterface ) Q_PROPERTY( QString name READ name ) Q_PROPERTY( QString category READ category ) Q_PROPERTY( bool immutable READ isImmutable WRITE setImmutable ) Q_PROPERTY( bool drawStandardBackground READ drawStandardBackground WRITE setDrawStandardBackground ) Q_PROPERTY( bool failedToLaunch READ failedToLaunch WRITE setFailedToLaunch ) Q_PROPERTY( bool needsConfiguring READ needsConfiguring WRITE setNeedsConfiguring ) Q_PROPERTY( QRectF boundingRect READ boundingRect ) public: typedef QList List; typedef QHash Dict; /** * @arg parent the QGraphicsItem this applet is parented to * @arg servideId the name of the .desktop file containing the * information about the widget * @arg appletId a unique id used to differentiate between multiple * instances of the same Applet type */ explicit Applet(QGraphicsItem* parent = 0, const QString& serviceId = QString(), uint appletId = 0); /** * This constructor is to be used with the plugin loading systems * found in KPluginInfo and KService. The argument list is expected * to have two elements: the KService service ID for the desktop entry * and an applet ID which must be a base 10 number. * * @arg parent a QObject parent; you probably want to pass in 0 * @arg args a list of strings containing two entries: the service id * and the applet id */ Applet(QObject* parent, const QVariantList& args); ~Applet(); /** * This method is called once the applet is loaded and added to a Corona. * If the applet requires a QGraphicsScene or has an particularly intensive * set of initialization routines to go through, consider implementing it * in this method instead of the contsructor. **/ virtual void init(); /** * @return the id of this applet */ uint id() const; /** * Returns the KConfigGroup to access the applets configuration. * * This config object will write to an instance * specific config file named \\rc * in the Plasma appdata directory. **/ KConfigGroup config() const; /** * Returns a config group with the name provided. This ensures * that the group name is properly namespaced to avoid collision * with other applets that may be sharing this config file * * @param group the name of the group to access **/ KConfigGroup config(const QString& group) const; /** * Saves state information about this applet. **/ void save(KConfigGroup* group) const; /** * Returns a KConfigGroup object to be shared by all applets of this * type. * * This config object will write to an applet-specific config object * named plasma_\rc in the local config directory. */ KConfigGroup globalConfig() const; /** * Returns the config skeleton object from this applet's package, * if any. * * @return config skeleton object, or 0 if none **/ ConfigXml* configXml() const; /** * Loads the given DataEngine * * Tries to load the data engine given by @p name. Each engine is * only loaded once, and that instance is re-used on all subsequent * requests. * * If the data engine was not found, an invalid data engine is returned * (see DataEngine::isValid()). * * Note that you should not delete the returned engine. * * @param name Name of the data engine to load * @return pointer to the data engine if it was loaded, * or an invalid data engine if the requested engine * could not be loaded */ Q_INVOKABLE DataEngine* dataEngine(const QString& name) const; /** * Accessor for the associated Package object if any. * Generally, only Plasmoids come in a Package. * * @return the Package object, or 0 if none **/ const Package* package() const; /** * Called when any of the geometry constraints have been updated. * This method calls constraintsUpdated, which may be reimplemented, * once the Applet has been prepared for updating the constraints. */ void updateConstraints(); /** * Called when any of the geometry constraints have been updated. * * This is always called prior to painting and should be used as an * opportunity to layout the widget, calculate sizings, etc. * * Do not call update() from this method; an update() will be triggered * at the appropriate time for the applet. * * @property constraint */ virtual void constraintsUpdated(); /** * Returns the current form factor the applet is being displayed in. * * @see Plasma::FormFactor */ virtual FormFactor formFactor() const; /** * Returns the location of the scene which is displaying applet. * * @see Plasma::Location */ virtual Location location() const; /** * Returns the area within which contents can be painted. If there is no * background, then this is equivalent to boundingRect().size() **/ QSizeF contentSize() const; /** * Returns an ideal size for the applet's content. * Applets can re-implement this to provide a suitable size based * on their contents. * * Unlike sizeHint() , contentSizeHint() does not include the * size of any borders surrounding the content area. * * The default implementation returns the sizeHint() of the applet's * layout if it has one, or a null size otherwise. */ virtual QSizeF contentSizeHint() const; /** * Returns a list of all known applets. * * @param category Only applets matchin this category will be returned. * Useful in conjunction with knownCategories. * If "Misc" is passed in, then applets without a * Categories= entry are also returned. * If an empty string is passed in, all applets are * returned. * @param parentApp the application to filter applets on. Uses the * X-KDE-ParentApp entry (if any) in the plugin info. * The default value of QString() will result in a * list containing only applets not specifically * registered to an application. * @return list of applets **/ static KPluginInfo::List knownApplets(const QString &category = QString(), const QString &parentApp = QString()); /** * Returns a list of all known applets associated with a certain mimetype. * * @return list of applets **/ static KPluginInfo::List knownAppletsForMimetype(const QString &mimetype); /** * Returns a list of all the categories used by * installed applets. * * @param parentApp the application to filter applets on. Uses the * X-KDE-ParentApp entry (if any) in the plugin info. * The default value of QString() will result in a * list containing only applets not specifically * registered to an application. * @return list of categories */ static QStringList knownCategories(const QString &parentApp = QString()); /** * @return true if this plasmoid provides a GUI configuration **/ bool hasConfigurationInterface(); /** * Reimplement this slot to show a configuration dialog. * * Let the user play with the plasmoid options. * Called when the user selects the configure entry * from the context menu. */ virtual void showConfigurationInterface(); /** * Attempts to load an applet * * Returns a pointer to the applet if successful. * The caller takes responsibility for the applet, including * deleting it when no longer needed. * * @param name the plugin name, as returned by KPluginInfo::pluginName() * @param applet unique ID to assign the applet, or zero to have one * assigned automatically. * @param args to send the applet extra arguments * @return a pointer to the loaded applet, or 0 on load failure **/ static Applet* loadApplet(const QString &name, uint appletId = 0, const QVariantList& args = QVariantList()); /** * Attempts to load an applet * * Returns a pointer to the applet if successful. * The caller takes responsibility for the applet, including * deleting it when no longer needed. * * @param info KPluginInfo object for the desired applet * @param applet unique ID to assign the applet, or zero to have one * assigned automatically. * @return a pointer to the loaded applet, or 0 on load failure **/ static Applet* loadApplet(const KPluginInfo& info, uint appletId = 0, const QVariantList& args = QVariantList()); /** * This method is called when the interface should be painted. * * @param painter the QPainter to use to do the paintiner * @param option the style options object * @param contentsRect the rect to paint within; automatically adjusted for * the background, if any **/ virtual void paintInterface(QPainter *painter, const QStyleOptionGraphicsItem *option, const QRect& contentsRect); /** * Returns the user-visible name for the applet, as specified in the * .desktop file. * * @return the user-visible name for the applet. **/ QString name() const; /** * Returns the plugin name for the applet */ QString pluginName() const; /** * Returns the icon related to this applet **/ QString icon() const; /** * Returns the category the applet is in, as specified in the * .desktop file. */ QString category() const; /** * Returns the color corresponding to the applet's category. */ QColor color() const; /** * Get the category of the given applet * * @param a KPluginInfo object for the applet */ static QString category(const KPluginInfo& applet); /** * Get the category of the given applet * * @param the name of the applet */ static QString category(const QString& appletName); /** * @return true if this applet is immutable **/ bool isImmutable() const; /** * Sets whether or not this applet is immutable or not. * * @arg immutable true if this applet should not be changeable **/ void setImmutable(bool immutable); /** * @return returns whether or not the applet is using the standard * background **/ bool drawStandardBackground(); /** * Sets whether the applet should automatically draw the standard * background. * * Defaults to false **/ void setDrawStandardBackground(bool drawBackground); /** * If for some reason, the applet fails to get up on its feet (the * library couldn't be loaded, necessary hardware support wasn't found, * etc..) this method returns true **/ bool failedToLaunch() const; /** * Call this method when the applet fails to launch properly. An * optional reason can be provided. * * Not that all children items will be deleted when this method is * called. If you have pointers to these items, you will need to * reset them after calling this method. * * @param failed true when the applet failed, false when it succeeded * @param reason an optional reason to show the user why the applet * failed to launch **/ void setFailedToLaunch(bool failed, const QString& reason = QString()); /** * @return true if the applet currently needs to be configured, * otherwise, false */ bool needsConfiguring() const; /** * When the applet needs to be configured before being usable, this * method can be called to show a standard interface prompting the user * to configure the applet * * Not that all children items will be deleted when this method is * called. If you have pointers to these items, you will need to * reset them after calling this method. * * @param needsConfiguring true if the applet needs to be configured, * or false if it doesn't */ void setNeedsConfiguring(bool needsConfiguring); enum { Type = Plasma::AppletType }; /** * Reimplemented from QGraphicsItem **/ int type() const; /** * Reimplemented from QGraphicsItem **/ QRectF boundingRect () const; /** * Returns a list of context-related QAction instances. * * This is used e.g. within the \a DesktopView to display a * contextmenu. * * @return A list of actions. The default implementation returns an * empty list. **/ virtual QList contextActions(); /** * Sets shadow for the given applet. */ void setShadowShown(bool); /** * Returns true if the given item has a shadow shown. */ bool isShadowShown() const; // reimplemented from LayoutItem // value is the same as contentSizeHint() if drawStandardBackground() is false // or contentSizeHint() plus the size of the border otherwise. virtual QSizeF sizeHint() const; Q_SIGNALS: /** * Emitted when the applet needs to take (or lose) keyboard focus. * * An applet should emit this signal to ensure that autohiding * elements stay unhidden and other bits of bookkeeping are * performed to ensure proper function. * * If you call watchForFocus on your applet, then this is handled for * the applet and it is not necessary to emit the signal directly. * * @param focus true if the applet is taking keyboard focus, false if * it is giving it up **/ void requestFocus( bool focus ); public Q_SLOTS: /** * Destroys the applet; it will be deleted and configurations reset. */ void destroy(); protected: /** * Called when a request to save the state of the applet is made * during runtime **/ virtual void saveState(KConfigGroup* config) const; /** * Returns the name of the applet. * * This will be the same for all instances of this applet. **/ QString globalName() const; /** * Returns a name unique to the instance of this applet. * * Useful for being able to refer directly to a particular * applet. Combines the global name with the applet id **/ QString instanceName() const; /** * Register widgets that can receive keyboard focus. * * Calling this results in an eventFilter being places on the widget. * * @param widget the widget to watch for keyboard focus * @param watch whether to start watching the widget, or to stop doing so */ void watchForFocus( QObject *widget, bool watch = true ); /** * Call this whenever focus is needed or not needed. * * You do not have to call this method for widgets that have * been registered with watchForFocus * * @see watchForFocus * @param focus whether to or not to request focus */ void needsFocus(bool focus); /** * Sets whether or not this applet provides a user interface for * configuring the applet. * * It defaults to false, and if true is passed in you should * also reimplement showConfigurationInterface() * * @arg hasInterface whether or not there is a user interface available **/ void setHasConfigurationInterface(bool hasInterface); /** * @internal event filter; used for focus watching **/ bool eventFilter( QObject *o, QEvent *e ); /** * Reimplemented from QGraphicsItem */ void contextMenuEvent(QGraphicsSceneContextMenuEvent *contextMenuEvent); /** * @internal for adjusting the shadow */ QVariant itemChange(GraphicsItemChange change, const QVariant &value); /** * @return the Containment, if any, this applet belongs to **/ Containment* containment() const; protected Q_SLOTS: /** * @internal used to show the configuration of an applet on first show */ void performSetupConfig(); private: Q_DISABLE_COPY(Applet) /** * Reimplemented from QGraphicsItem **/ void paintWidget(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = 0); class Private; Private* const d; }; } // Plasma namespace /** * Register an applet when it is contained in a loadable module */ #define K_EXPORT_PLASMA_APPLET(libname, classname) \ K_PLUGIN_FACTORY(factory, registerPlugin();) \ K_EXPORT_PLUGIN(factory("plasma_applet_" #libname)) #endif // multiple inclusion guard