:date: 2016-11-28

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Monday, November 28, 2016
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About dashboard widgets and user preferences
============================================

Now finally I can write a bit more about :ticket:`1284`.

It was triggered by a simple request from Aurélie: they wanted to make
it configurable per user whether
:class:`lino.modlib.notify.models.MyMessages` is to be visible in the
main admin screen or not.

My first idea was to add an option "Display messages in main screen".
But in a discussion with Hamza I understood:

    I am reluctant to add this option because it makes the user
    preferences more complex.  Simple users wiil be irritated because
    they don't know what to put there...

    Actually my feeling is deeper: I doubt whether this option makes
    sense *at all*.  This option is not only irritating for *simple*
    users.
    
    I also think that even those people who did not want to see "Mes
    messages" (because they rely on their emails), even these people
    sometimes want to see their messages in the main screen. The real
    solution is to make *all* those admin main items configurable.

    The admin main items are like the "widgets" used sometimes by CMS
    frameworks.

    Actually we should not have an option "Display messages in main
    screen", but a panel where every user can customize which widgets they
    want to see, and in which order. And maybe whether they should be
    initially collapsed... or whether there should be several columns...

The idea caused a little series of changes:

- Lino now has the notion of "user preferences"
  (:mod:`lino.core.userprefs`).  Required a little APi extension
  :meth:`lino.core.plugin.Plugin.setup_user_prefs`.

- I started to rename the "admin main page" to "dashboard", wrote a
  :mod:`lino.core.dashboard` module for encapsulating the concept and a
  new plugin :mod:`lino.modlib.dashboard` for letting users define
  "widgets" for (optinally) configuring their dashboard.

As a side effect of this, the
:class:`lino_xl.lib.blogs.models.LatestEntries` table now also has a
slave summary panel. Also note that this table is actually not a slave
table (it has no master). I extended the slave summary panel so that
it works also on master tables.

En passant I discovered and fixed a subtle bug: The
:attr:`use_websockets <lino.core.site.Site.use_websockets>` option
must be a class attribute of :class:`lino.core.site.Site` (and not of
:class:`lino.modlib.notify.Plugin`). The problem caused `channels` to
be installed even when `use_websockets` was set to `False`.  It is
analog to :attr:`use_java <lino.core.site.Site.use_java>`.

Also en passant some more optimizations for :ticket:`923`: The
:class:`lino.modlib.notify.models.MyMessages` table now has a custom
summary so that the messages are being displayed as list items. And
when you open it in its own window (where you have an ExtJS grid),
then you now have an action to mark all messages as seen. It is
currently not possible to render that action as a html link in the
slave summary. And it is now labelled "My notification messages"
(instead of just "My messages").


TODO:

- (:ref:`welfare.specs.chatelet` or :ref:`welfare.specs.eupen`)
  Explorateur --> Système --> All dashboard widgets : 'NoneType'
  object has no attribute 'get_request_queryset'

- rename :meth:`get_slave_summary` to `get_summar_html`.