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

**

** Copyright (C) 2008-2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (developer.feedback@nokia.com)

**

** This file is part of the HbCore module of the UI Extensions for Mobile.

**

** GNU Lesser General Public License Usage

** This file may be used under the terms of the GNU Lesser General Public

** License version 2.1 as published by the Free Software Foundation and

** appearing in the file LICENSE.LGPL included in the packaging of this file.

** Please review the following information to ensure the GNU Lesser General

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** In addition, as a special exception, Nokia gives you certain additional

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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

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

/*!

    \class HbDeviceDialogPlugin

    \brief HbDeviceDialogPlugin is an abstract base class for device dialog widget plugins.

    Device dialogs are widgets which are shown on top of all applications by a device dialog

    service. The service queues and displays device dialogs according to client requests and

    system state. The service displays widgets in it's window (HbApplication window).

    <b>Platform dependent.</b> Currently server is implemented only for Symbian platform. On other platforms,

    device dialog are displayed on client's mainwindow.

    Device dialog widgets are created by plugins. The service loads a plugin to create and display

    a device dialog. A single plugin may implement several different dialogs or just one.

    Dialogs are identified by a string. By convention the string should follow

    inverted domain name format. For example com.nokia.hb.devicedialog.note/1.0.

    Function deviceDialogTypes() returns a list of dialog types the plugin implements.

    Appending version number into device dialog type string enables versioning of device dialogs.

    A plugin should handle versioning by returning device dialog type string for all versions it

    implements in deviceDialogTypes() and then in createDeviceDialog() create a device dialog

    instance compatible with the version requested. This could always be the latest version if it

    is backwards compatible with older versions. Device dialog framework is unaware of version

    numbers in type strings. It performs string comparison of the whole string when searching

    for a plugin.

    Device dialogs are divided into five groups: generic, notification, indicator-menu, security

    and critical groups. The group dictates how and when a dialog is shown. Generic and

    notification dialogs are intended for application use. Indicator, security and critical dialogs are

    for platform. Each dialog indicates which group it belongs to. The group need not be fixed.

    It may change depending on create parameters.

    Device dialog groups may prioritize (queueing) device dialogs in respect to other groups.

    In addition each device dialog has an individual queueing priority that may affect how it is

    shown inside a group. Currently there is no queueing implemented for device dialogs. All

    dialogs are displayed in order requests are received. Z-order of dialogs on display is

    determined by popup framework. Last dialog created is on top. Device dialog framework

    manipulates Z-order of dialogs. Device dialogs themselves should not change the popup Z-order.

    Device dialog widgets have to be derived from HbPopup either directly or by ancestry.

    <div style="color:gray">

    <b>For future needs. Not implemented.</b>

    Device dialog may be shared by several device dialog clients. Each client can update the

    device dialog and receive signals from it equally. Clients attach to a shared device dialog

    instance by agreeing on an unique tag. The tag is appended into device dialog type with a %

    separator. For example here the tag "#1" is appended into device dialog type

    "hb.devicedialog.note/1.0%#1". If a device dialog instance exists, a client is attached into it

    instead of creating a new one. To allow sharing, plugin must set

    HbDeviceDialogPlugin::SharedDeviceDialog.

    </div>

    <b>Symbian.</b>Plugins are run by a server with platform security capabilities ProtServ, SwEvent,

    TrustedUI and ReadDeviceData.

    Plugins are responsible for maintaining system security for their own part. If plugin

    performs operations that may compromise security or want's to limit access to specific

    clients, it should check client security credentials in accessAllowed() function.

    Device dialog framework calls this function before creating or attaching client to a

    plugin if HbDeviceDialogPlugin::SecurityCheck is set. Access is denied if the

    function returns false. In addition, HbDeviceDialogPlugin constructor has a check which

    allows only device dialog service to load plugins derived from it.

    <b>Symbian.</b>Device dialog plugins can be installed into a device. If a plugin doesn't have

    required platform security capabilities it will not load. Plugins are searched from device's

    local drives. The search order is rom-drives, non-removable drives and removable drives. Once

    a pluging is found the search stops. This implies that plugins on rom drives cannot be

    overriden by plugins on other drives.

    <b>Platform dependent.</b>Plugin location differs depending on platform. On Symbian, device dialog

    plugin stubs (.qtplugin) are located in /resource/plugins/devicedialogs directory and executables

    in /sys/bin directory. On other platforms plugin executables are searched from application's

    current directory and HB_PLUGINS_DIR/devicedialogs directory.

    Well behaving dialog widget should observe following rules:

    - Should not create and show other dialogs

    - No calls to show(), hide() or setVisible()

    - Not setting popup Z-order

    - No time consuming operations performed

    Creating a device dialog plugin and widget involves following steps.

    - Set in .pro file TEMPLATE = lib and CONFIG += hb plugin

    - Derive a class from HbPopup or derivatives and HbDeviceDialogInterface

    \code

    class HbSampleMessageBoxWidget : public HbMessageBox, public HbDeviceDialogInterface

    {

        Q_OBJECT

    \endcode

    - Implement device dialog widget and HbDeviceDialogInterface interface. Declare and emit

      deviceDialogClosed and optionally deviceDialogData signals. Do not call show(), hide() or

      setVisible() in the plugin. Device dialog framework calls show() to display the widget.

    \code

    public:

        bool setDeviceDialogParameters(const QVariantMap &parameters);

        int deviceDialogError() const;

        void closeDeviceDialog(bool byClient);

        HbPopup *deviceDialogWidget() const;

    signals:

        void deviceDialogClosed();

        void deviceDialogData(QVariantMap data);

    \endcode

    - Wrap the widget into a plugin derived from HbDeviceDialogPlugin

    \code

    class HbSampleMessageBoxPlugin : public HbDeviceDialogPlugin

    {

        Q_OBJECT

    \endcode

    - Implement HbDeviceDialogPlugin pure virtual functions

    \code

        bool accessAllowed(const QString &deviceDialogType,

            const QVariantMap &parameters, const QVariantMap &securityInfo) const;

        HbDeviceDialogInterface *createDeviceDialog(const QString &deviceDialogType, const QVariantMap &parameters);

        bool deviceDialogInfo(const QString &deviceDialogType,

            const QVariantMap &parameters, DeviceDialogInfo *info) const;

        QStringList deviceDialogTypes() const;

        PluginFlags pluginFlags() const;

        int error() const;

    \endcode

    <b> Class diagram of the sample plugin:</b>

    \dot

    digraph G {

        rankdir=LR;

        subgraph cluster_class_diagram {

            style=solid;

            node [shape = box, style=solid, fontsize = 10];

            HbSampleMessageBoxPlugin [label = "HbSampleMessageBoxPlugin"];

            QObject [label = "QObject"];

            HbDeviceDialogPluginInterface [label = "HbDeviceDialogPluginInterface"];

            HbDeviceDialogPlugin [label = "HbDeviceDialogPlugin"];

            edge [fontsize = 10, style = filled];

            QObject -> HbDeviceDialogPlugin [label = "is a"];

            HbDeviceDialogPluginInterface -> HbDeviceDialogPlugin [label = "is a"];

            HbDeviceDialogPlugin -> HbSampleMessageBoxPlugin [label = "is a"];

            HbSampleMessageBoxWidget [label = "HbSampleMessageBoxWidget"];

            HbMessageBox [label = "HbMessageBox"];

            HbDeviceDialogInterface [label = "HbDeviceDialogInterface"];

            HbMessageBox -> HbSampleMessageBoxWidget [label = "is a"];

            HbDeviceDialogInterface -> HbSampleMessageBoxWidget [label = "is a"];

            edge [fontsize = 10, style = dotted];

            HbSampleMessageBoxPlugin -> HbSampleMessageBoxWidget  [label = "creates"];

        }

        subgraph cluster_key {

            label = "Key";

            style=solid;

            node [shape = box, style=solid, fontsize = 10];

            Class1 [label = "Class"];

            Class2 [label = "Class"];

            Class3 [label = "Class"];

            edge [fontsize = 10, style = filled];

            Class2 -> Class1 [label = "generalization"];

            edge [fontsize = 10, style = dotted];

            Class3 -> Class1 [label = "dependency"];

            }

    }

    \enddot

    Sample plugin implementations can be found in src/hbplugins/devicedialogs directory.

    \sa HbDeviceDialogPluginInterface HbDeviceDialogInterface HbDeviceDialog HbPopup

    \stable

    \hbcore

*/

/*!

    \enum HbDeviceDialogPlugin::PluginFlag

    Defines flags for the plugin.

    \sa pluginFlags

*/

/*!

    \var HbDeviceDialogPlugin::PluginFlag HbDeviceDialogPlugin::NoPluginFlags

    No flags specified.

*/

/*!

    \var HbDeviceDialogPlugin::PluginFlag HbDeviceDialogPlugin::PreloadPlugin

    Load plugin on startup. This also implies KeepPluginLoaded flag.

*/

/*!

    \var HbDeviceDialogPlugin::PluginFlag HbDeviceDialogPlugin::KeepPluginLoaded

    Keep the plugin loaded in memory. Flag is ignored for third party plugins.

*/

/*!

    \enum HbDeviceDialogPlugin::DeviceDialogGroup

    Defines device dialog groups. Each of these groups have different rules for showing

    device dialogs.

    \sa deviceDialogInfo DeviceDialogInfo

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogGroup HbDeviceDialogPlugin::GenericDeviceDialogGroup

    Common device dialogs.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogGroup HbDeviceDialogPlugin::DeviceNotificationDialogGroup

    Device notification dialogs.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogGroup HbDeviceDialogPlugin::IndicatorGroup

    Indicators. Only platform device dialogs may belong to this group.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogGroup HbDeviceDialogPlugin::SecurityGroup

    Screen saver and alarm dialogs. Only platform device dialogs may belong to this group.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogGroup HbDeviceDialogPlugin::CriticalGroup

    High priority dialogs shown on top other dialogs. Only platform device dialogs may

    belong to this group.

*/

/*!

    \enum HbDeviceDialogPlugin::DeviceDialogFlag

    Defines flags for a device dialog created by the plugin.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogFlag HbDeviceDialogPlugin::NoDeviceDialogFlags

    No flags specified.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogFlag HbDeviceDialogPlugin::SharedDeviceDialog

    <em>For future needs. Not used.</em>

    The device dialog may be shared. Several clients may share the same device dialog instance.

    If the flag is not set, device dialog service doesn't allow sharing of the device dialog.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogFlag HbDeviceDialogPlugin::SecurityCheck

    If the flag is set, device dialog service calls accessAllowed() before creating or

    attaching to a device dialog widget.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogFlag HbDeviceDialogPlugin::SingleInstance

    If the flag is set, only one instance of the device dialog widget is allowed at

    one time. Attempt to launch the widget while one exists results in an error to be

    returned to the client.

*/

/*!

    \var HbDeviceDialogPlugin::DefaultPriority

    Default priority value to return in DeviceDialogInfo.

*/

/*!

    \struct HbDeviceDialogPlugin::DeviceDialogInfo

    \brief Structure containing device dialog widget information.

    Passed as a parameter to HbDeviceDialogPlugin::deviceDialogInfo().

    \sa HbDeviceDialogPlugin

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogInfo::group

    Group the device dialog widget belongs to. HbDeviceDialogPlugin::DeviceDialogGroup.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogInfo::flags

    Device dialog flags. HbDeviceDialogPlugin::DeviceDialogFlag.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogInfo::priority

    <em>For future needs. Not used</em>.

    Device dialog display priority. Determines queuing order of dialogs. Fill with

    HbDeviceDialogPlugin::DefaultPriority.

*/

/*!

    \var HbDeviceDialogPlugin::DeviceDialogInfo::spare

    Spare space for future needs.

*/

/*!

    \fn virtual bool HbDeviceDialogPlugin::accessAllowed(const QString &deviceDialogType,

        const QVariantMap &parameters, const QVariantMap &securityInfo) const = 0

    Checks if client is allowed use the device dialog that the plugin creates. Device dialog service

    calls this function before creating a device dialog or attaching into an existing one if flag

    HbDeviceDialogPlugin::SecurityCheck is set. The implementation is operating system dependent.

    On Symbian this may involve checking client's platform security capabilities or secure ID for

    example. Returns true if client is allowed to use the device dialog.

     \param deviceDialogType Device dialog type.

     \param parameters Device dialog parameters.

     \param securityInfo Information for security check. Content is operating system dependent.

     The format is <key, value> pairs.

     Currently only Symbian is defined.

     <table>

         <caption> Symbian security information </caption>

         <tr>

         <th>Key</th>

         <th>Value type</th>

         <th>Description</th>

         </tr>

         <tr>

         <td>"sym-secureId"</td>

         <td>quint32</td>

         <td>Client's secure ID</td>

         </tr>

         <tr>

         <td>"sym-vendorId"</td>

         <td>quint32</td>

         <td>Client's vendor ID</td>

         </tr>

         <tr>

         <td>"sym-caps"</td>

         <td>quint32</td>

         </tr>

     </table>

*/

/*!

    \fn virtual bool HbDeviceDialogPlugin::deviceDialogInfo(const QString &deviceDialogType,

        const QVariantMap &parameters, DeviceDialogInfo *info) const = 0

    Gets information of the device dialog created by the plugin. Device dialog manager calls this

    function before creating the device dialog widget to check

    HbDeviceDialogPlugin::DeviceDialogGroup, HbDeviceDialogPlugin::DeviceDialogFlag and priority.

    Returns true if device dialog information returned is valid.

    \param deviceDialogType Device dialog type.

    \param parameters Device dialog parameters.

    \param info Structure the plugin fills with an information of the device dialog it

    creates with the deviceDialogType and parameters.

*/

/*!

    \fn virtual QStringList HbDeviceDialogPlugin::deviceDialogTypes() const = 0

    Returns a list of device dialog types the plugin implements. A plugin may implement several

    device dialog types. By convention device dialog type strings should follow inverted domain

    name format. For example com.nokia.hb.devicedialog.note/1.0

*/

/*!

    \fn virtual HbDeviceDialogPlugin::Flags HbDeviceDialogPlugin::pluginFlags() const = 0

    Returns plugin flags.

*/

/*!

    \fn virtual int HbDeviceDialogPlugin::error() const = 0

    Returns an error last occurred. Error code ranges are defined in HbDeviceDialog. The code is

    passed to a client by device dialog framework.

*/

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

/*!

    \class HbDeviceDialogInterface

    \brief HbDeviceDialogInterface is an abstract interface class for a device dialog widget.

    Device dialogs are widgets which are shown on top of all applications by a device dialog service.

    Widgets are created by plugins. Device dialog service uses this interface to update widget

    parameters and close widget.

    The widget implementation must implement this interface. In addition it must provide a

    deviceDialogClosed() signal and optionally deviceDialogData() signal if data needs to be

    passed to a client.

    Device dialog widgets must be derived from HbPopup or derivatives as described in

    HbDeviceDialogPlugin.

    Following popup convention, the widget is not visible immediately after is created.

    Device dialog framework calls HbPopup::show() to display the widget. The service may change

    The service may change visibility of the widget by HbPopup::setVisible function.

    The widget should close itself by either a timeout or user interaction. It may also be closed

    gracefully either by system or the client by a closeDeviceDialog() function. It is assumed that

    the widget object can be ungracefully destroyed (delete) at any time.

    \b Signals:

    \b void \b deviceDialogClosed()