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/**
\page architecture Document/View Architecture
\author Ariya Hidayat (<a href="mailto:ariya@kde.org">ariya@kde.org</a>)
\date 2004
\par Status:
FINISHED
<p>MVC (Model/View/Controller) means that the application consists of three
big parts, the <i>Model</i> which holds the data structure and objects,
the <i>View</i> which shows the model to the user and the <i>Controller</i>
which handles user inputs and changes the model accordingly. Like other
office applications, KSpread uses the Document/View architecture, a slightly
different variant of MVC where the View and Controller are put together
as one part.</p>
<p>In order of its complexity scale, KSpread code has to be well separated,
i.e. the <i>Document</i> and the <i>View</i>. We may also call them as
<i>back-end</i> and <i>front-end</i> respectively. Right now part of which
should belong to the Document sometimes has access to the View. For example,
a cell stores information about its metrics in pixels (which is zoom dependent),
knows whether it is visible to the user or not (which is view dependent), etc.
This needs to be changed.</p>
<p>One easy way to decide whether some stuff or relationship must really really
alienated in the Document is to imagine that somebody wants to create another
View (front-end) to the Document object model (back-end) that is being worked
on. Say, one decent guy would like to copy the look-and-feel of classic Lotus
1-2-3 (for whatever reason we are not really interested in here); so basically
to some extent he can take most part of the KSpread back-end and glue a new
user interface around the code.</p>
*/
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