--- a/doc/book/en/04-develop-views.en.txt Fri Nov 21 17:36:42 2008 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,126 +0,0 @@
-.. -*- coding: utf-8 -*-
-
-
-Developing the user interface with Views
-========================================
-
-Before moving to this section, make sure you read the `Essentials`
-section in the Introduction.
-
-Tip: when modifying views, you do not need to restart the local
-server. Just save the file in your editor and reload the page in your
-browser to see the changes.
-
-The selection/view principle
-----------------------------
-
-With `LAX`, views are defined by Python classes. A view includes:
-
-- an identifier (all objects in `LAX` are entered in a registry
- and this identifier will be used as a key)
-
-- a filter to select the resulsets it can be applied to
-
-`LAX` provides a lot of standard views, for a complete list, you
-will have to read the code in directory ``ginco/web/views/`` (XXX
-improve doc).
-
-For example, the view named ``primary`` is the one used to display
-a single entity.
-
-If you want to change the way a ``BlogEntry`` is displayed, just
-override the view ``primary`` in ``BlogDemo/views.py`` ::
-
- 01. from ginco.web.views import baseviews
- 02.
- 03. class BlogEntryPrimaryView(baseviews.PrimaryView):
- 04.
- 05. accepts = ('BlogEntry',)
- 06.
- 07. def cell_call(self, row, col):
- 08. entity = self.entity(row, col)
- 09. self.w(u'<h1>%s</h1>' % entity.title)
- 10. self.w(u'<p>published on %s in category %s</p>' % \
- 11. (entity.publish_date.strftime('%Y-%m-%d'), entity.category))
- 12. self.w(u'<p>%s</p>' % entity.text)
-
-The above source code defines a new primary view (`line 03`) for
-``BlogEntry`` (`line 05`).
-
-Since views are applied to resultsets and resulsets can be tables of
-data, it is needed to recover the entity from its (row,col)
-coordinates (`line 08`). We will get to this in more detail later.
-
-The view has a ``self.w()`` method that is used to output data. Here `lines
-09-12` output HTML tags and values of the entity's attributes.
-
-When displaying same blog entries as before, you will notice that the
-page is now looking much nicer.
-
-.. image:: images/lax-book.09-new-view-blogentry.en.png
- :alt: blog entries now look much nicer
-
-Let us now improve the primary view of a blog ::
-
- 01. class BlogPrimaryView(baseviews.PrimaryView):
- 02.
- 03. accepts = ('Blog',)
- 04.
- 05. def cell_call(self, row, col):
- 06. entity = self.entity(row, col)
- 07. self.w(u'<h1>%s</h1>' % entity.title)
- 08. self.w(u'<p>%s</p>' % entity.description)
- 09. rset = self.req.execute('Any E WHERE E entry_of B, B eid "%s"' % entity.eid)
- 10. self.wview('primary', rset)
-
-In the above source code, `lines 01-08` are similar to the previous
-view we defined.
-
-At `line 09`, a simple request in made to build a resultset with all
-the entities linked to the current ``Blog`` entity by the relationship
-``entry_of``. The part of the framework handling the request knows
-about the schema and infer that such entities have to be of the
-``BlogEntry`` kind and retrieves them.
-
-The request returns a selection of data called a resultset. At
-`line 10` the view 'primary' is applied to this resultset to output
-HTML.
-
-**This is to be compared to interfaces and protocols in object-oriented
-languages. Applying a given view to all the entities of a resultset only
-requires the availability, for each entity of this resultset, of a
-view with that name that can accepts the entity.**
-
-Assuming we added entries to the blog titled `MyLife`, displaying it
-now allows to read its description and all its entries.
-
-.. image:: images/lax-book.10-blog-with-two-entries.en.png
- :alt: a blog and all its entries
-
-**Before we move forward, remember that the selection/view principle is
-at the core of `LAX`. Everywhere in the engine, data is requested
-using the RQL language, then HTML/XML/text/PNG is output by applying a
-view to the resultset returned by the query. That is where most of the
-flexibility comes from.**
-
-[WRITE ME]
-
-* implementing interfaces, calendar for blog entries
-* show that a calendar view can export data to ical
-
-We will implement the ginco.interfaces.ICalendarable interfaces on
-entities.BloEntry and apply the OneMonthCalendar and iCalendar views
-to resultsets like "Any E WHERE E is BlogEntry"
-
-* create view "blogentry table" with title, publish_date, category
-
-We will show that by default the view that displays
-"Any E,D,C WHERE E publish_date D, E category C" is the table view.
-Of course, the same can be obtained by calling
-self.wview('table',rset)
-
-* in view blog, select blogentries and apply view "blogentry table"
-* demo ajax by filtering blogentry table on category
-
-we did the same with 'primary', but with tables we can turn on filters
-and show that ajax comes for free.