Home/ Questions/Q 8576461
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-11T19:55:44+00:00

I have a grok’ed plone.directives.form code below: class EditForm(TreeFormMixin, form.SchemaForm): Edit form for our

  • 0

I have a grok’ed plone.directives.form code below:

class EditForm(TreeFormMixin, form.SchemaForm):
    """
    Edit form for our model.

    We got one dummy button which allows us to manually inspect the data postback values.
    """
    grok.context(ISiteRoot)
    grok.name("dgftreeselect-test")
    grok.require('zope2.View')

    ignoreContext = True
    schema = IFormSchema

    label = u"Tree selection demo and manual testing"

    @button.buttonAndHandler(u'Turbo boost')
    def handleApply(self, action):

        data, errors = self.extractData()
        if errors:
            self.status = self.formErrorsMessage
            return

        raise ActionExecutionError(Invalid(u"Please see that data stays intact over postback"))

it results to this form – which is not that good looking:

DGFs in the action

Since it is a demo form I’d like to keep all the related material in the same .py file. However, as the form is ugly looking, I’d like to inject a <style> CSS block on the page from a Python source code string to fix some of the most outstanding issues with the CSS styles.

What kind of hooks plone.app.forms / BrowserViews provide to inject your own <style> block in the <head> or in any part of the resulting HTML page? I prefer not to create any additional files and CSS registrations for this task.

Full source:

https://github.com/miohtama/collective.z3cform.dgftreeselect/blob/master/src/collective/z3cform/dgftreeselect/testform.py

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    plone.app.z3cform and Zope browser views don’t provide any hooks to inject custom things into the head directly, but you can use a custom template by specifying the template attribute in the form class:

    template = grok.Template('path/to/template.pt')

    And then in template.pt, fill the style_slot to include your styles. The entire template could look like this:

    <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"
      xmlns:tal="http://xml.zope.org/namespaces/tal"
      xmlns:metal="http://xml.zope.org/namespaces/metal"
      xmlns:i18n="http://xml.zope.org/namespaces/i18n"
      lang="en"
      metal:use-macro="context/main_template/macros/master"
      i18n:domain="plone">
<body>

<metal:block fill-slot="style_slot">
    <style type="text/css">
      /* insert styles here */
    </style>
</metal:block>

<metal:content-core fill-slot="main">
  <metal:content-core define-macro="content-core">
      <tal:button metal:use-macro="context/@@ploneform-macros/titlelessform" />
  </metal:content-core>
</metal:content-core>

</body>
</html>

    This is not a best practice since the styles must be served every time the widget is rendered. Instead it’s usually better to register CSS in the portal_css tool.

    • 0