mmappfw_plat/mpx_base_view_plugins_api/inc/mpxviewpluginqt.h
branchRCL_3
changeset 56 63223d4fd956
parent 55 6c1dfe4da5dd
child 59 666f9a5a90a9
equal deleted inserted replaced
55:6c1dfe4da5dd 56:63223d4fd956
     1 /*
       
     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
       
     3 * All rights reserved.
       
     4 * This component and the accompanying materials are made available
       
     5 * under the terms of "Eclipse Public License v1.0"
       
     6 * which accompanies this distribution, and is available
       
     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".
       
     8 *
       
     9 * Initial Contributors:
       
    10 * Nokia Corporation - initial contribution.
       
    11 *
       
    12 * Contributors:
       
    13 *
       
    14 * Description: 
       
    15 *
       
    16 */
       
    17 
       
    18 #ifndef MPXVIEWPLUGIN_H
       
    19 #define MPXVIEWPLUGIN_H
       
    20 
       
    21 #ifdef BUILD_VIEWFRAMEWORK
       
    22 #define VFDLL_EXPORT Q_DECL_EXPORT
       
    23 #else
       
    24 #define VFDLL_EXPORT Q_DECL_IMPORT
       
    25 #endif
       
    26 
       
    27 #include <QObject>
       
    28 
       
    29 class QGraphicsWidget;
       
    30 class MpxViewPlugin;
       
    31 
       
    32 class VFDLL_EXPORT MpxPluginViewInterface {
       
    33 
       
    34   public:
       
    35     virtual MpxViewPlugin *viewPlugin() = 0;
       
    36     
       
    37     };
       
    38 
       
    39 Q_DECLARE_INTERFACE(MpxPluginViewInterface , "org.nokia.mmdt.MpxViewPlugin/1.0" );
       
    40 
       
    41 class VFDLL_EXPORT MpxViewPlugin : public QObject, public MpxPluginViewInterface {
       
    42 
       
    43     Q_OBJECT
       
    44     Q_INTERFACES(MpxPluginViewInterface)
       
    45 
       
    46   public:
       
    47 	
       
    48 	/* COMMENT:
       
    49 	 * following two methods are kind of second-phase create & destroy. Rationale for this step is that
       
    50 	 * we need some way to promote lazy resources allocation (on application demand) and early resource
       
    51 	 * deallocation (again, on application direct command).
       
    52 	 */
       
    53 
       
    54 	/**
       
    55 	 * createView is the second operation (after plugin construction which is done somewhere 
       
    56 	 * in the plugin framework) executed in the application layer to make a fully operational 
       
    57 	 * View Plugin descendant.
       
    58 	 * I should allocate all of those resources that are required by plugin, but which are
       
    59 	 * too expensive to allocate in constructor (eg. in case of plugin prefetching).
       
    60 	 */
       
    61 	virtual void createView() = 0;	
       
    62 
       
    63 	/**
       
    64 	 * destroyView is an operation that should be executed just before plugin deletion.
       
    65 	 * Implementation should destroy all of resources allocated during createView execution.
       
    66 	 * It's reason d'etre is based on a fact, that application doesn't controll when exactly
       
    67 	 * plugin will be deleted, so destructor execution could be postponed still holding resources.
       
    68 	 */
       
    69 	virtual void destroyView() = 0;
       
    70 
       
    71 	/* COMMENT:
       
    72 	 * view activation and deactivation are reversible operations
       
    73 	 * that allows us to give up resources that we could temporary deallocate when that 
       
    74 	 * specific view plugin goes into background.
       
    75 	 */
       
    76 
       
    77 	/**
       
    78 	 * Called to notice view activation.
       
    79 	 */
       
    80 	virtual void activateView() = 0;
       
    81 
       
    82 	/**
       
    83 	 * Called to notice view deactivation.
       
    84 	 */
       
    85 	virtual void deactivateView() = 0;
       
    86 
       
    87 	/**
       
    88 	 * gives actual view component, ready to put somewhere into the app layout.
       
    89 	 * However, beware that calling to activate/deactivate in the meantime
       
    90 	 * can invalidate that pointer.
       
    91 	 * 
       
    92 	 * NOTE: Returned type is choosen to be as generic as possible, 
       
    93 	 * so please ensure that it fulfills all your needs (it was HbView* before)
       
    94 	 */
       
    95 	virtual QGraphicsWidget* getView() = 0;
       
    96 
       
    97   public slots:
       
    98 
       
    99 	/**
       
   100 	 * Signalled by application when orientation has changed.
       
   101 	 */	
       
   102 	virtual void orientationChange(Qt::Orientation orientation) = 0;
       
   103 
       
   104 	/**
       
   105 	 * Implementation should take care either to implement
       
   106        * go-back operation internally or to emit proper
       
   107 	 * command signal to delegate that responsibility to
       
   108 	 * framework (eg. to switch to previous view).
       
   109 	 */	
       
   110 	virtual void back() = 0;
       
   111 
       
   112   signals:
       
   113 
       
   114 	/**
       
   115 	 * Command is the only way to notify from plugin to application
       
   116 	 * about action needed to be executed.
       
   117 	 *
       
   118 	 * @param aCommand  enumeration of command type. 
       
   119 	 * Currently supported are: ViewBack, CloseApp, GoToNowPlaying, GoToCollectionView.
       
   120 	 * NOTE: It should be specified how to determine between broadly supported operations 
       
   121 	 * (back, close etc.) and application/plugin specific (go to collection, go to now playing etc.)
       
   122 	 *
       
   123 	 * There is also one major issue here, that there is no guaranted order of command delivery,
       
   124 	 * so there is second option to use common observer pattern. Should be discussed.
       
   125 	 */	
       
   126 	void command(int aCommand);
       
   127 	
       
   128   public:
       
   129 
       
   130     virtual MpxViewPlugin *viewPlugin() { return this; }
       
   131 
       
   132 };
       
   133 
       
   134 #endif /*MPXVIEWPLUGIN_H_*/
       
   135