--- a/doc/book/en/devweb/form.rst Thu May 06 08:24:46 2010 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,216 +0,0 @@
-HTML form construction
-----------------------
-
-CubicWeb provides the somewhat usual form / field / widget / renderer abstraction
-to provide generic building blocks which will greatly help you in building forms
-properly integrated with CubicWeb (coherent display, error handling, etc...),
-while keeping things as flexible as possible.
-
-A **form** basically only holds a set of **fields**, and has te be bound to a
-**renderer** which is responsible to layout them. Each field is bound to a
-**widget** that will be used to fill in value(s) for that field (at form
-generation time) and 'decode' (fetch and give a proper Python type to) values
-sent back by the browser.
-
-The **field** should be used according to the type of what you want to edit.
-E.g. if you want to edit some date, you'll have to use the
-:class:`cubicweb.web.formfields.DateField`. Then you can choose among multiple
-widgets to edit it, for instance :class:`cubicweb.web.formwidgets.TextInput` (a
-bare text field), :class:`~cubicweb.web.formwidgets.DateTimePicker` (a simple
-calendar) or even :class:`~cubicweb.web.formwidgets.JQueryDatePicker` (the JQuery
-calendar). You can of course also write your own widget.
-
-
-.. automodule:: cubicweb.web.views.autoform
-
-
-Example of bare fields form
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-We want to define a form doing something else than editing an entity. The idea is
-to propose a form to send an email to entities in a resultset which implements
-:class:`IEmailable`. Let's take a simplified version of what you'll find in
-:mod:`cubicweb.web.views.massmailing`.
-
-Here is the source code:
-
-.. sourcecode:: python
-
- def sender_value(form):
- return '%s <%s>' % (form._cw.user.dc_title(), form._cw.user.get_email())
-
- def recipient_choices(form, field):
- return [(e.get_email(), e.eid) for e in form.cw_rset.entities()
- if e.get_email()]
-
- def recipient_value(form):
- return [e.eid for e in form.cw_rset.entities() if e.get_email()]
-
- class MassMailingForm(forms.FieldsForm):
- __regid__ = 'massmailing'
-
- needs_js = ('cubicweb.widgets.js',)
- domid = 'sendmail'
- action = 'sendmail'
-
- sender = ff.StringField(widget=TextInput({'disabled': 'disabled'}),
- label=_('From:'),
- value=sender_value)
-
- recipient = ff.StringField(widget=CheckBox(),
- label=_('Recipients:'),
- choices=recipient_choices,
- value=recipients_value)
-
- subject = ff.StringField(label=_('Subject:'), max_length=256)
-
- mailbody = ff.StringField(widget=AjaxWidget(wdgtype='TemplateTextField',
- inputid='mailbody'))
-
- form_buttons = [ImgButton('sendbutton', "javascript: $('#sendmail').submit()",
- _('send email'), 'SEND_EMAIL_ICON'),
- ImgButton('cancelbutton', "javascript: history.back()",
- stdmsgs.BUTTON_CANCEL, 'CANCEL_EMAIL_ICON')]
-
-Let's detail what's going on up there. Our form will hold four fields:
-
-* a sender field, which is disabled and will simply contains the user's name and
- email
-
-* a recipients field, which will be displayed as a list of users in the context
- result set with checkboxes so user can still choose who will receive his mailing
- by checking or not the checkboxes. By default all of them will be checked since
- field's value return a list containing same eids as those returned by the
- vocabulary function.
-
-* a subject field, limited to 256 characters (hence we know a
- :class:`~cubicweb.web.formwidgets.TextInput` will be used, as explained in
- :class:`~cubicweb.web.formfields.StringField`)
-
-* a mailbody field. This field use an ajax widget, defined in `cubicweb.widgets.js`,
- and whose definition won't be shown here. Notice though that we tell this form
- need this javascript file by using `needs_js`
-
-Last but not least, we add two buttons control: one to post the form using
-javascript (`$('#sendmail')` being the jQuery call to get the element with DOM id
-set to 'sendmail', which is our form DOM id as specified by its `domid`
-attribute), another to cancel the form which will go back to the previous page
-using another javascript call. Also we specify an image to use as button icon as a
-resource identifier (see :ref:`external_resources`) given as last argument to
-:class:`cubicweb.web.formwidgets.ImgButton`.
-
-To see this form, we still have to wrap it in a view. This is pretty simple:
-
-.. sourcecode:: python
-
- class MassMailingFormView(form.FormViewMixIn, EntityView):
- __regid__ = 'massmailing'
- __select__ = implements(IEmailable) & authenticated_user()
-
- def call(self):
- form = self._cw.vreg['forms'].select('massmailing', self._cw,
- rset=self.cw_rset)
- self.w(form.render())
-
-As you see, we simply define a view with proper selector so it only apply to a
-result set containing :class:`IEmailable` entities, and so that only users in the
-managers or users group can use it. Then in the `call()` method for this view we
-simply select the above form and write what its `.render()` method returns.
-
-When this form is submitted, a controller with id 'sendmail' will be called (as
-specified using `action`). This controller will be responsible to actually send
-the mail to specified recipients.
-
-Here is what it looks like:
-
-.. sourcecode:: python
-
- class SendMailController(Controller):
- __regid__ = 'sendmail'
- __select__ = authenticated_user() & match_form_params('recipient', 'mailbody', 'subject')
-
- def publish(self, rset=None):
- body = self._cw.form['mailbody']
- subject = self._cw.form['subject']
- eids = self._cw.form['recipient']
- # eids may be a string if only one recipient was specified
- if isinstance(eids, basestring):
- rset = self._cw.execute('Any X WHERE X eid %(x)s', {'x': eids})
- else:
- rset = self._cw.execute('Any X WHERE X eid in (%s)' % (','.join(eids)))
- recipients = list(rset.entities())
- msg = format_mail({'email' : self._cw.user.get_email(),
- 'name' : self._cw.user.dc_title()},
- recipients, body, subject)
- if not self._cw.vreg.config.sendmails([(msg, recipients]):
- msg = self._cw._('could not connect to the SMTP server')
- else:
- msg = self._cw._('emails successfully sent')
- raise Redirect(self._cw.build_url(__message=msg))
-
-
-The entry point of a controller is the publish method. In that case we simply get
-back post values in request's `form` attribute, get user instances according
-to eids found in the 'recipient' form value, and send email after calling
-:func:`format_mail` to get a proper email message. If we can't send email or
-if we successfully sent email, we redirect to the index page with proper message
-to inform the user.
-
-Also notice that our controller has a selector that deny access to it to
-anonymous users (we don't want our instance to be used as a spam relay), but also
-check expected parameters are specified in forms. That avoids later defensive
-programming (though it's not enough to handle all possible error cases).
-
-To conclude our example, suppose we wish a different form layout and that existent
-renderers are not satisfying (we would check that first of course :). We would then
-have to define our own renderer:
-
-.. sourcecode:: python
-
- class MassMailingFormRenderer(formrenderers.FormRenderer):
- __regid__ = 'massmailing'
-
- def _render_fields(self, fields, w, form):
- w(u'<table class="headersform">')
- for field in fields:
- if field.name == 'mailbody':
- w(u'</table>')
- w(u'<div id="toolbar">')
- w(u'<ul>')
- for button in form.form_buttons:
- w(u'<li>%s</li>' % button.render(form))
- w(u'</ul>')
- w(u'</div>')
- w(u'<div>')
- w(field.render(form, self))
- w(u'</div>')
- else:
- w(u'<tr>')
- w(u'<td class="hlabel">%s</td>' % self.render_label(form, field))
- w(u'<td class="hvalue">')
- w(field.render(form, self))
- w(u'</td></tr>')
-
- def render_buttons(self, w, form):
- pass
-
-We simply override the `_render_fields` and `render_buttons` method of the base form renderer
-to arrange fields as we desire it: here we'll have first a two columns table with label and
-value of the sender, recipients and subject field (form order respected), then form controls,
-then a div containing the textarea for the email's content.
-
-To bind this renderer to our form, we should add to our form definition above:
-
-.. sourcecode:: python
-
- form_renderer_id = 'massmailing'
-
-API
-~~~
-
-.. automodule:: cubicweb.web.formfields
-.. automodule:: cubicweb.web.formwidgets
-.. automodule:: cubicweb.web.views.forms
-.. automodule:: cubicweb.web.views.formrenderers
-
-.. Example of entity fields form