CSensrvChannelFinder Class Reference
Link against: SensrvClient.lib
#include <sensrvchannelfinder.h>
Detailed Description
The CSensrvChannelFinder class provides an API that allows clients to discover the sensor channels supported by Sensor Services and receive notifications when channels are installed and uninstalled.
The channel specific header files e.g. for orientation, acceleration, proximity, will document whether a secure id, vendor id or a set of capabilities, if any, is required by the client to be able to view a channel or receive notifications for it. See the channel specific header files for these requirements.
On instantiation of this class a session connection to the Sensor Server is made. The Sensor server is a transient server and is started, if not already running, when a session connection is made. The sensor server is shutdown when a device-configured timeout period expires after the last session connection has been dropped. The Sensor Server will not shutdown if there is a session connection to it.
Each item in RSensrvChannelInfoList returned by FindChannelsL() contains a channel Id which is only valid for the lifetime of the sensor server. If a client requires that this id remains unchanged then the client must ensure that an instance of either CSensrvChannelFinder or CSensrvChannel remains instantiated. This keeps a session connection with the server open which prevents the sensor server from shutting down.
- See also:
- CSensrvChannel
- Dll sensrvclient.lib
- Since:
- S60 5.0
Constructor & Destructor Documentation
| CSensrvChannelFinder::CSensrvChannelFinder | ( | | ) | |
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Member Function Documentation
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Retrieves a list of channels that meet the supplied search parameters.
Only channels for which the client has the required secure id, vendor id and capabilities will be returned. See class description for further information. - Since:
- S60 5.0
- Parameters:
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| aChannelList | List of all channels matching the supplied search parameters. Each TSensrvChannelInfo instance in the list can be used to open a channel. Empty list is returned if no matching channels are found. | | aSearchParameters | Parameters for which matching channels are to be found. To omit a field from the search use zero (if integer) or empty string (if descriptor). If all fields are zero or empty string all channels provided by the system will be returned. ChannelId, DataItemSize and Reserved data will be ignored if set. |
- Leave:
- One of the system-wide error codes
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Two-phased constructor.
- Since:
- S60 5.0
- Returns:
- Pointer to created CSensrvChannelFinder object
- Leave:
- KErrNoMemory
- Leave:
- One of the system-wide error codes
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Two-phased constructor.
- Since:
- S60 5.0
- Returns:
- Pointer to created CSensrvChannelFinder object that is placed on the cleanup stack.
- Leave:
- KErrNoMemory
- Leave:
- One of the system-wide error codes
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Listens for channels that meet the supplied search parameters.
Only channels for which the client has the required secure id, vendor id and capabilities will be returned. See class description. Listening can be stopped by providing a NULL parameter for the aChannelListener argument. - Since:
- S60 5.0
- Parameters:
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| aChannelListener | Pointer to channel listener callback instance. The channel listener must be valid until the CSensrvChannelFinder object is destroyed or listening has been stopped. Listening can be stopped using a NULL parameter. | | aSearchParameters | Parameters for which matching channel notifications are to be provided. To omit a field from the search use zero (if integer) or empty string (if descriptor). If all fields are zero or empty string all channels provided by the system will be returned. ChannelId, DataItemSize and Reserved data will be ignored if set. |
- Leave:
- KErrAlreadyExists if channel listener has already been set
- Leave:
- One of the system-wide error codes
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The documentation for this class was generated from the following file:
