patForms RFC #0001: Context aware datasources
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$Id: rfc0001.txt 269 2005-07-31 11:27:00Z schst $

Author      : schst
Created     : 2005-06-14
Status      : Implemented in changeset [268]
Implemented : 2005-07-31

Scope of change
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Datasources, which act as data providers like the Enum element should
be aware of the context they are used in. This way they can be more than
arrays that are created on demand.

Rationale
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 * Language dependent Enum values
 * Values depend on other attributes of the element

Functionality
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 * The elements that support datasources need to pass the element itself
   as the sole argument to the getValues() method or the datasource callback.
   This influences the following elements
   * Enum
   * Set
   * Combobox
   * RadioGroup
 * patForms could also provide a createDatasource() method. In order to
   achieve this, we should standardize the API of the datasources that ship
   with patForms. The easiest way probably would be passing an array to the
   constructor, like the Propel Datasource already does.

Security considerations
-----------------------
 * datasource may access and modify the elements

Speed impact
------------
None.

Dependencies
------------
This will at least break the existing examples.
Up to now, the name of the element has been passed to the datasource,
if the datasource was a callback and not a datasource object. This
functionality is not documented anywhere and not used consistently in
patForms, so a change would probably be a good idea.

Related documents
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None.

Comments
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None yet.

History
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$Log$
Revision 1.1  2005/06/14 16:12:51  schst
started the RFC