epoc32/include/sensrvchannelfinder.h
branchSymbian2
changeset 2 2fe1408b6811
parent 0 061f57f2323e
child 4 837f303aceeb
equal deleted inserted replaced
1:666f914201fb 2:2fe1408b6811
     1 sensrvchannelfinder.h
     1 /*
       
     2 * Copyright (c) 2008 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 the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
       
     6 * which accompanies this distribution, and is available
       
     7 * at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
       
     8 *
       
     9 * Initial Contributors:
       
    10 * Nokia Corporation - initial contribution.
       
    11 *
       
    12 * Contributors:
       
    13 *
       
    14 * Description:  Sensor Channel API
       
    15 *
       
    16 */
       
    17 
       
    18 
       
    19 
       
    20 #ifndef SENSRVCHANNELFINDER_H
       
    21 #define SENSRVCHANNELFINDER_H
       
    22 
       
    23 //  INCLUDES
       
    24 #include <e32base.h>
       
    25 #include <sensrvtypes.h>
       
    26 #include <sensrvchannelinfo.h>
       
    27 
       
    28 // CLASS DECLARATION
       
    29 class MSensrvChannelListener;
       
    30 
       
    31 /**
       
    32 * The CSensrvChannelFinder class provides an API that allows clients to discover the sensor
       
    33 * channels supported by Sensor Services and receive notifications when channels are installed
       
    34 * and uninstalled.
       
    35 * 
       
    36 * The channel specific header files e.g. for orientation, acceleration, proximity, will document
       
    37 * whether a secure id, vendor id or a set of capabilities, if any, is required by the client to
       
    38 * be able to view a channel or receive notifications for it. See the channel specific header
       
    39 * files for these requirements.
       
    40 * 
       
    41 * On instantiation of this class a session connection to the Sensor Server is made. The Sensor
       
    42 * server is a transient server and is started, if not already running, when a session connection
       
    43 * is made. The sensor server is shutdown when a device-configured timeout period expires after
       
    44 * the last session connection has been dropped. The Sensor Server will not shutdown if there is
       
    45 * a session connection to it.
       
    46 * 
       
    47 * Each item in RSensrvChannelInfoList returned by FindChannelsL() contains a channel Id which is
       
    48 * only valid for the lifetime of the sensor server. If a client requires that this id remains
       
    49 * unchanged then the client must ensure that an instance of either CSensrvChannelFinder or
       
    50 * CSensrvChannel remains instantiated. This keeps a session connection with the server open which
       
    51 * prevents the sensor server from shutting down.
       
    52 *
       
    53 * @see CSensrvChannel
       
    54 * @lib sensrvclient.lib
       
    55 * @since S60 5.0
       
    56 */
       
    57 NONSHARABLE_CLASS( CSensrvChannelFinder ): public CBase
       
    58     {
       
    59     public:
       
    60     /**
       
    61     * Two-phased constructor.
       
    62     *
       
    63     * @since S60 5.0
       
    64     * @return Pointer to created CSensrvChannelFinder object
       
    65     * @leave  KErrNoMemory
       
    66     * @leave  One of the system-wide error codes
       
    67     */  
       
    68     IMPORT_C static CSensrvChannelFinder* NewL();
       
    69 
       
    70     /**
       
    71     * Two-phased constructor.
       
    72     *
       
    73     * @since S60 5.0
       
    74     * @return Pointer to created CSensrvChannelFinder object that is placed on the cleanup stack.
       
    75     * @leave  KErrNoMemory
       
    76     * @leave  One of the system-wide error codes
       
    77     */  
       
    78     IMPORT_C static CSensrvChannelFinder* NewLC();
       
    79   
       
    80     public:
       
    81     /**
       
    82     * Retrieves a list of channels that meet the supplied search parameters. Only
       
    83     * channels for which the client has the required secure id, vendor id and
       
    84     * capabilities will be returned. See class description for further information.
       
    85     *     
       
    86     * @since S60 5.0
       
    87     * @param  aChannelList List of all channels matching the supplied search 
       
    88     *         parameters. Each TSensrvChannelInfo instance in the list can be used
       
    89     *         to open a channel. Empty list is returned if no matching channels are
       
    90     *         found.
       
    91     * @param  aSearchParameters Parameters for which matching channels are to be
       
    92     *         found. To omit a field from the search use zero (if integer) or
       
    93     *         empty string (if descriptor). If all fields are zero or empty string
       
    94     *         all channels provided by the system will be returned. ChannelId,
       
    95     *         DataItemSize and Reserved data will be ignored if set.
       
    96     * @leave  One of the system-wide error codes
       
    97     */
       
    98     virtual void FindChannelsL( RSensrvChannelInfoList& aChannelList, 
       
    99                                 const TSensrvChannelInfo& aSearchParameters ) = 0;
       
   100     
       
   101     /**
       
   102     * Listens for channels that meet the supplied search parameters. Only channels
       
   103     * for which the client has the required secure id, vendor id and capabilities
       
   104     * will be returned. See class description. Listening can be stopped by providing
       
   105     * a NULL parameter for the aChannelListener argument.
       
   106     * 
       
   107     * @since S60 5.0
       
   108     * @param  aChannelListener Pointer to channel listener callback instance. The
       
   109     *         channel listener must be valid until the CSensrvChannelFinder object
       
   110     *         is destroyed or listening has been stopped. Listening can be stopped
       
   111     *         using a NULL parameter.
       
   112     * @param  aSearchParameters Parameters for which matching channel notifications
       
   113     *         are to be provided. To omit a field from the search use zero (if integer)
       
   114     *         or empty string (if descriptor). If all fields are zero or empty string
       
   115     *         all channels provided by the system will be returned. ChannelId,
       
   116     *         DataItemSize and Reserved data will be ignored if set.
       
   117     * @leave  KErrAlreadyExists if channel listener has already been set
       
   118     * @leave  One of the system-wide error codes
       
   119     */
       
   120     virtual void SetChannelListenerL( MSensrvChannelListener* aChannelListener,
       
   121                                 const TSensrvChannelInfo& aSearchParameters  ) = 0;
       
   122 
       
   123     public:
       
   124     /**
       
   125     * Default constructor. 
       
   126     */
       
   127     CSensrvChannelFinder();
       
   128     };
       
   129 
       
   130 
       
   131 #endif //SENSRVCHANNELFINDER_H
       
   132 
       
   133 // End of File