kdelibs/kdeui/notifications/knotification.h

/* This file is part of the KDE libraries
   Copyright (C) 2005-2006 Olivier Goffart <ogoffart at kde.org>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License version 2 as published by the Free Software Foundation.

   This library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/


#ifndef KNOTIFICATION_H
#define KNOTIFICATION_H

#include <kdeui_export.h>
#include <kcomponentdata.h>

#include <QtGui/QPixmap>
#include <QtCore/QObject>
#include <QtCore/QPair>

#include <QWidget>
#include <QDBusError>

/**
 * KNotification is used to notify the user of an event.
 * 
 * \section introduction
 *
 * There are two main kinds of notifications:
 *
 * @li Feedback events:
 * For notifying the user that he/she just performed an operation, like maximizing a window. This
 * allows to play sounds when a dialog appears. This is an instant notification.  It ends
 * automatically after a small timeout.
 *
 * @li persistent notifications:
 * Notify when the user received a new message, or when something else important happened the user
 * has to know about.  This notification has a start and a end.  It begins when the event actually
 * occurs, and finishes when the message is acknowledged or read.
 *
 * Example of a persistent notification in an instant messaging application:
 * The application emits the notification when the message is actually received, and closes it only
 * when the user has read the message (when the message window has received the focus) using the
 * close() slot. Persistent notifications must have the Persistent flag.
 *
 * By default a notification will use the application name as title, but you can also provide a
 * brief text in the title and a more precise description in the body text. This is especially
 * useful for notifications coming from applications which should be considered "part of the
 * system", like a battery monitor or a network connection manager. For example a battery indicator
 * could use "Low Battery" as a title and "Only 12 minutes left." as a body text.
 *
 * In order to perform a notification, you need to create a description file, which contains
 * default parameters of the notification, and use KNotification::event at the place in the
 * application code where the notification occurs. The returned KNotification pointer may be used
 * to connect signals or slots
 *
 * \section file The global config file
 * Your application should install a file called:
 *  <em>$KDEDIR/share/appname/appname.notifyrc</em>
 *
 * You can do this with the following CMake command:
 * install(FILES appname.notifyrc DESTINATION ${KDE4_DATA_INSTALL_DIR}/appname))
 *
 *  This file contains  mainly 3 parts
 *   <ol><li>\ref global "Global information"</li>
 *       <li>\ref context "Context information"</li>
 *       <li>\ref events "Definition of individual events"</li></ol>
 *
 *  \subsection global Global information
 * The global part looks like that
 * <pre>
        [Global]
        IconName=Filename
        Comment=Friendly Name of app
        Name=Name of app
 * </pre>
 * The icon filename is just the name, without extension, it's found with the KIconLoader. The
 * Comment field will be used in KControl to describe the application. The Name field is optional
 * and may be used as the application name for popup, if Name is not present, Comment is used
 * instead
 * 
 * \subsection context Context information
 * 
 * This part consists of hints for the configuration widget
 *  <pre>
        [Context/group]
        Name=Group name
        Comment=The name of the group for contacts

        [Context/folder]
        Name=Group name
 *  </pre>
 * The second part of the groupname is the context identifier. It should not contain special
 * characters. The Name field is the one the user will see (and which is translated)
 *
 * \subsection events Definition of Events
 *
 * The definition of the events forms the most important part of the config file
 * <pre>
        [Event/newmail]
        Name=New email
        Comment=You have got a new email
        Contexts=folder,group
        Action=Sound|Popup

        [Event/contactOnline]
        Name=Contact goes online
        Comment=One of your contact has been connected
        Contexts=group
        Sound=filetoplay.ogg
        Action=None
 *  </pre>
 * These are the default settings for each notifiable event. Action is the string representing the
 * action. Actions can be added to the KNotify daemon as plugins, by deriving from KNotifyPlugin.
 * At the time of writing, the following actions are available: Taskbar, Sound, Popup, Logfile
 * and Execute. Actions can be combined by seperating them with '|'.
 *
 * Contexts is a comma separated list of possible context for this event.
 *
 * \section userfile The user's config file
 *
 * This is an implementation detail, and is described here for your information.
 *
 * In the config file, there are two parts: the event configuration, and the context information
 * \subsection context Context information
 *  These are hints for the configuration dialog. They contain both the internal id of the context,
 * and the user visible string.
 *  <pre>
        [Context/group]
        Values=1:Friends,2:Work,3:Family
 *  </pre>
 * \subsection event Events configuration
 * This contains the configuration of events for the user. It contains the same fields as the
 * description file. The key of groups is in the form 
 * <em>Event/&lt;EventName&gt;/&lt;ContextName&gt;/&lt;ContextValue&gt;</em>
 * <pre>
        [Event/contactOnline]
        Action=Sound
        Sound=/usr/share/sounds/super.ogg

        [Event/contactOnline/group/1]
        Action=Popup|Sound
 * </pre>
 * 
 * \section example Example of code
 * 
 * This portion of code will fire the event for the "contactOnline" event
 * 
 * @code
        KNotification *notification= new KNotification ("contactOnline", widget);
        notification->setText(i18n("The contact <i>%1</i> has gone online", contact->name());
        notification->setPixmap(contact->pixmap());
        notification->setActions(QStringList(i18n("Open chat")));

        foreach(const QString &group , contact->groups()) {
            notification->addContext("group", group);
        }

        connect(notification, SIGNAL(activated(unsigned int)), contact , SLOT(slotOpenChat()));

        notification->sendEvent();
 * @endcode
 * 
 * @author Olivier Goffart  \<ogoffart at kde.org\>
 */
class KDEUI_EXPORT KNotification : public QObject
{
    Q_OBJECT
public:
    /**
     * Sometimes the user may want different notifications for the same event, depending the source
     * of the event.  Example, you want to be notified for mails that arrive in your folder
     * "personal inbox" but not for those in "spam" folder
     * 
     * A notification context is a pair of two strings. The first string is a key from what the
     * context is.  example "group" or "filter" (not translated). The second is the id of the
     * context. In our example, the group id or the filter id in the applications. These strings
     * are the ones present in the config file, and are in theory not shown in the user interface.
     * 
     * The order of contexts in the list is is important, the most important context  should be
     * placed first. They are processed in that order when the notification occurs.
     *
     * @see event
     */
    typedef QPair<QString,QString> Context;
    typedef QList< Context > ContextList;

    enum NotificationFlag
    {
        /**
         * The notification will be automatically closed after a timeout. (this is the default)
         */
        CloseOnTimeout = 0x00,

        /**
         * When the notification is activated, raise the notification's widget.
         *
         * This will change the desktop, raise the window, and switch to the tab.
         * @todo  doesn't work yet
         */
        RaiseWidgetOnActivation = 0x01,

        /**
         * The notification will NOT be automatically closed after a timeout. You will have to
         * track the notification, and close it with the close function manually when the event is
         * done, otherwise there will be a memory leak
         */
        Persistent = 0x02,

        /**
         * The notification will be automatically closed if the widget() becomes activated.
         *
         * If the widget is already activated when the notification occurs, the notification will
         * be closed after a small timeout. This only works if the widget is the toplevel widget
         * @todo make it work with tabulated widget
         */
        CloseWhenWidgetActivated = 0x03,

        /**
         * @internal
         * The event is a standard kde event, and not an event of the application
         */
        DefaultEvent= 0xF000
            
    };
    Q_DECLARE_FLAGS(NotificationFlags , NotificationFlag)

    /**
     * default events you can use in the event function
     */
    enum StandardEvent { Notification , Warning , Error , Catastrophe };

    /**
     * Create a new notification.
     * 
     * You have to use sendEvent to show the notification.
     * 
     * The pointer is automatically deleted when the event is closed.
     *
     * Make sure you use one of the NotificationFlags CloseOnTimeOut or CloseWhenWidgetActivated,
     * if not, you have to close the notification yourself.
     *
     * @param eventId is the name of the event
     * @param widget is a widget where the notification reports to
     * @param flags is a bitmask of NotificationFlag
    */
    explicit KNotification(const QString &eventId , QWidget *widget = nullptr, const NotificationFlags &flags = CloseOnTimeout);

    /**
     * Create a new notification.
     *
     * You have to use sendEvent to show the notification.
     *
     * The pointer is automatically deleted when the event is closed.
     *
     * Make sure you use one of the NotificationFlags CloseOnTimeOut or
     * CloseWhenWidgetActivated, if not,
     * you have to close the notification yourself.
     *
     * @since 4.4
     *
     * @param eventId is the name of the event
     * @param flags is a bitmask of NotificationFlag
     * @param parent parent object
     */
    explicit KNotification(const QString &eventId, const NotificationFlags &flags, QObject *parent = NULL);

    ~KNotification();

    /**
     * @brief the widget associated to the notification
     *
     * If the widget is destroyed, the notification will be automatically cancelled. If the widget
     * is activated, the notification will be automatically closed if the NotificationFlags specify
     * that
     *
     * When the notification is activated, the widget might be raised. Depending on the
     * configuration, the taskbar entry of the window containing the widget may blink.
     */
    QWidget *widget() const;
    /**
     * Set the widget associated to the notification. The notification is reparented to the new
     * widget.
     *
     * \see widget()
     * @param widget the new widget
     */
    void setWidget(QWidget *widget);

    /**
     * @return the name of the event
     */
    QString eventId() const;

    /**
     * @return the notification title
     * @see setTitle
     * @since 4.3
     */
    QString title() const;
    /**
     * Set the title of the notification popup. If no title is set, the application name will be
     * used.
     *
     * @param title the title
     * @since 4.3
     */
    void setTitle(const QString &title);

    /**
     * @return the notification text
     * @see setText
     */
    QString text() const;
    /**
     * Set the notification text that will appear in the popup.
     * 
     * The text is shown in a QLabel, you should make sure to escape any html that is needed. You
     * can use some of the Katie basic html tags.
     *
     * @param text the text
     */
    void setText(const QString &text);

    /**
     * \return the pixmap shown in the popup
     * \see setPixmap
     */
    QPixmap pixmap() const;
    /**
     * Set the pixmap that will be shown in the popup.
     * @param pix the pixmap
     */
    void setPixmap(const QPixmap &pix);

    /**
     * @return the list of actions
     */
    QStringList actions() const;
    /**
     * Set the list of actions link shown in the popup.
     * @param actions the list of actions
     */
    void setActions(const QStringList &actions);

    /**
     * @return the list of contexts, see KNotification::Context
     */
    ContextList contexts() const;
    /**
     * Set the list of contexts, see KNotification::Context
     * 
     * The list of contexts must be set before calling sendEvent;
     */
    void setContexts(const ContextList &contexts);
    /**
     * Append a context at the list of contexts, see KNotificaiton::Context
     * @param context the context which is added
     */
    void addContext(const Context &context);
    /**
     * @overload
     * @param context_key is the key of the context
     * @param context_value is the value of the context
     */
    void addContext(const QString &context_key, const QString &context_value);

    /**
     * @return the notification flags.
     */
    NotificationFlags flags() const;
    /**
     * Set the notification flags. Should be called before sendEvent().
     */
    void setFlags(const NotificationFlags &flags);

    /**
     * The componentData is used to determine the location of the config file. By default, kapp is
     * used
     * @param componentData the new componentData
     */
    void setComponentData(const KComponentData &componentData);

Q_SIGNALS:
    /**
     * Emit only when the default activation has occurred
     */
    void activated();
    /**
     * Emit when an action has been activated.
     * @param action will be 0 is the default aciton was activated, or any action id
     */
    void activated(unsigned int action);
    /**
     * Convenience signal that is emitted when the first action is activated.
     */
    void action1Activated();
    /**
     * \overload
     */
    void action2Activated();
    /**
     * \overload
     */
    void action3Activated();

    /**
     * Emitted when the notification is closed. Both when it is activated or if it is just ignored.
     */
    void closed();

    /**
     * The notification has been ignored
     */
    void ignored();

public Q_SLOTS:
    /**
     * @brief Activate the action specified action
     * If the action is zero, then the default action is activated
     */
    void activate(unsigned int action = 0);

    /**
     * Close the notification without activating it.
     *
     * This will delete the notification.
     */
    void close();

    /**
     * @brief Raise the widget.
     * This will change the desktop, activate the window, and the tab if needed.
     */
    void raiseWidget();

    /**
     * The notification will automatically be closed if all presentations are finished. if you want
     * to show your own presentation in your application, you should use this function, so it will
     * not be automatically closed when there is nothing to show.
     * 
     * Don't forgot to deref, or the notification may be never closed if there is no timeout.
     * @see ref
     */
    void ref();
    /**
     * remove a reference made with ref()
     * the notification may be closed when calling this.
     * @see ref
     */
    void deref();

    /**
     * Emit or re-emit the event.
     */
    void sendEvent();

    /**
     * @internal
     * update the texts, the icon, and the actions of one existing notification
     */
    void update();

private Q_SLOTS:
    void slotReceivedId(int);
    void slotReceivedIdError(const QDBusError &);

private:
    struct Private;
    Private *const d;

protected:
    /**
     * reimplemented for internal reasons
     */
    virtual bool eventFilter(QObject *watched, QEvent *event);

public:
    /**
     * @brief emit an event
     *
     * This method creates the KNotification, setting every parameter, and fire the event. You
     * don't need to call sendEvent
     *
     * A popup may be displayed or a sound may be played, depending the config.
     *
     * @return a KNotification. You may use that pointer to connect some signals or slot. The
     * pointer is automatically deleted when the event is closed.
     *
     * Make sure you use one of the CloseOnTimeOut or CloseWhenWidgetActivated, if not, you have
     * to close yourself the notification.
     *
     * @note the text is shown in a QLabel, you should escape HTML, if needed.
     *
     * @param eventId is the name of the event
     * @param title is title of the notification to show in the popup.
     * @param text is the text of the notification to show in the popup.
     * @param pixmap is a picture which may be shown in the popup.
     * @param widget is a widget where the notification reports to
     * @param flags is a bitmask of NotificationFlag
     * @param componentData used to determine the location of the config file. by default, kapp is used
     * @since 4.4
     */
    static KNotification* event(const QString &eventId, const QString &title, const QString &text,
                                const QPixmap &pixmap = QPixmap(), QWidget *widget = nullptr,
                                const NotificationFlags &flags = CloseOnTimeout,
                                const KComponentData &componentData = KComponentData());

    /**
     * @brief emit a standard event
     *
     * @overload
     *
     * This will emit a standard event
     *
     * @param eventId is the name of the event
     * @param text is the text of the notification to show in the popup.
     * @param pixmap is a picture which may be shown in the popup.
     * @param widget is a widget where the notification reports to
     * @param flags is a bitmask of NotificationFlag
     * @param componentData used to determine the location of the config file. by default, kapp is used
     */
    static KNotification* event(const QString &eventId, const QString &text = QString(),
                                const QPixmap &pixmap = QPixmap(), QWidget *widget = nullptr,
                                const NotificationFlags &flags = CloseOnTimeout,
                                const KComponentData &componentData = KComponentData());

    /**
     * @brief emit a standard event
     *
     * @overload
     *
     * This will emit a standard event
     *
     * @param eventId is the name of the event
     * @param text is the text of the notification to show in the popup
     * @param pixmap is a picture which may be shown in the popup
     * @param widget is a widget where the notification reports to
     * @param flags is a bitmask of NotificationFlag 
     */
    static KNotification* event(StandardEvent eventId, const QString &text = QString(),
                                const QPixmap &pixmap = QPixmap(), QWidget *widget = nullptr,
                                const NotificationFlags &flags = CloseOnTimeout);

    /**
     * @brief emit a standard event
     *
     * @overload
     *
     * This will emit a standard event
     *
     * @param eventId is the name of the event
     * @param title is title of the notification to show in the popup.
     * @param text is the text of the notification to show in the popup
     * @param pixmap is a picture which may be shown in the popup
     * @param widget is a widget where the notification reports to
     * @param flags is a bitmask of NotificationFlag
     * @since 4.4
     */
    static KNotification* event(StandardEvent eventId, const QString &title, const QString &text,
                                const QPixmap &pixmap = QPixmap(), QWidget *widget = nullptr,
                                const NotificationFlags &flags = CloseOnTimeout);

    /**
     * This is a simple substitution for QApplication::beep()
     *
     * @param reason a short text explaining what has happened (may be empty)
     * @param widget the widget the notification refers to
     */
    static void beep(const QString &reason = QString() , QWidget *widget = nullptr);
    
    // prevent warning
    using QObject::event;
};

Q_DECLARE_OPERATORS_FOR_FLAGS(KNotification::NotificationFlags)

#endif