Central -Repository Overview

Central -Repository OverviewThe Central Repository stores data such as application settings, -component settings, configuration parameters and data used for localisation -and customisation. -

Purpose

The central repository was introduced to -avoid the use of multiple .ini files specific to each application. Typical -uses are persisting application data such as default file names, locale settings -and user preferences from one session to another: data of this kind can also -be used by device creaters to customise a device. Examples include phone book -data, bookmarks, event logging and default keyboard layout.

Required background

The central repository is used -in the implementation of many libraries. Application developers using these -libraries generally do not need to access the central repository API directly. -Developers maintaining and extending such libraries need to know how to use -the API to read and modify repository data and set up change notification. -Developers creating new extensions to Symbian, such as device drivers need -to know when it is appropriate to use the central repository to persist settings. -They will also need to understand the mechanism of key spaces and initialisation -files used to implement the central repository and how to create repository -files, as explained in Central -Repository Initialisation Files Guide. Product integrators and device -creators need to know where in ROM central repository data can reside, to -know the installation mechanism and to understand the impact on data security.

Key concepts and terms

Repository: A data structure holding data to be persisted for a component or application, -equivalent to a file. Also called a keyspace.
Setting: An item of data in a repository, equivalent to a line in a file. Also -called a key.
Initialisation file: The text file from which a repository is created.
Keyspaces: Another term for a repository.
Access policies: Read or write permissions on a setting or group of settings.

Architecture

Many applications and modules come -with a data structure called a repository or keyspace which is used to persist -application data. The Central Repository is the component which stores and -manages repositories. Repositories are created and initialised individually -along with their associated application on installation, or as a group when -a device is built by device creators. The purpose of the Central Repository -API is to enable application developers and device creators to modify repository -data and to provide notification of changes to a repository.

Conceptually, -the Central Repository is comparable to a folder, an individual repository -to a file and a setting to a line in a file. In fact repositories are implemented -as binary files held at various locations in memory and are accessed through -C++ classes which encapsulate them with a single API. Repositories are created -with the applications to which they refer at device build time or at installation -by the Application Installer on runtime. The Central Repository API is only -used to access repositories, not to create them.

APIs

The Central Repository API provides the CRepository class -to provide access to repositories.

- - - -API -Description - - - - -

CRepository

Provides the functionality to access the repository created with -an application.

- - -

CCenRepNotifyHandler

Creates notification of changes to a repository.

- - -

MCenRepNotifyHandlerCallback

A callback interface to be implemented to respond to change notification.

- - - -

Typical uses

The Central Repository is typically -used by applications such as messaging services to retrieve logins, localisation -data and information needed for interprocess communication.

-Central Repository -Guide -Central Repository -Access Guide + + + + + +Central +Repository OverviewThe Central Repository stores data such as application settings, +component settings, configuration parameters and data used for localisation +and customisation. +

Purpose

The central repository was introduced to +avoid the use of multiple .ini files specific to each application. Typical +uses are persisting application data such as default file names, locale settings +and user preferences from one session to another: data of this kind can also +be used by device creaters to customise a device. Examples include phone book +data, bookmarks, event logging and default keyboard layout.

Required background

The central repository is used +in the implementation of many libraries. Application developers using these +libraries generally do not need to access the central repository API directly. +Developers maintaining and extending such libraries need to know how to use +the API to read and modify repository data and set up change notification. +Developers creating new extensions to Symbian, such as device drivers need +to know when it is appropriate to use the central repository to persist settings. +They will also need to understand the mechanism of key spaces and initialisation +files used to implement the central repository and how to create repository +files, as explained in Central +Repository Initialisation Files Guide. Product integrators and device +creators need to know where in ROM central repository data can reside, to +know the installation mechanism and to understand the impact on data security.

Key concepts and terms

Repository: A data structure holding data to be persisted for a component or application, +equivalent to a file. Also called a keyspace.
Setting: An item of data in a repository, equivalent to a line in a file. Also +called a key.
Initialisation file: The text file from which a repository is created.
Keyspaces: Another term for a repository.
Access policies: Read or write permissions on a setting or group of settings.

Architecture

Many applications and modules come +with a data structure called a repository or keyspace which is used to persist +application data. The Central Repository is the component which stores and +manages repositories. Repositories are created and initialised individually +along with their associated application on installation, or as a group when +a device is built by device creators. The purpose of the Central Repository +API is to enable application developers and device creators to modify repository +data and to provide notification of changes to a repository.

Conceptually, +the Central Repository is comparable to a folder, an individual repository +to a file and a setting to a line in a file. In fact repositories are implemented +as binary files held at various locations in memory and are accessed through +C++ classes which encapsulate them with a single API. Repositories are created +with the applications to which they refer at device build time or at installation +by the Application Installer on runtime. The Central Repository API is only +used to access repositories, not to create them.

APIs

The Central Repository API provides the CRepository class +to provide access to repositories.

+ + + +API +Description + + + + +

CRepository

Provides the functionality to access the repository created with +an application.

+ + +

CCenRepNotifyHandler

Creates notification of changes to a repository.

+ + +

MCenRepNotifyHandlerCallback

A callback interface to be implemented to respond to change notification.

+ + + +

Typical uses

The Central Repository is typically +used by applications such as messaging services to retrieve logins, localisation +data and information needed for interprocess communication.

+Central Repository +Guide +Central Repository +Access Guide

\ No newline at end of file