TemplateTag: render_model_add_block

README.TXT

# templatetag: render_model_add_block

## Description

Currently django CMS has a templatetag: render_model_add, which is used like this: `{% render_model_add mymodel_instance %}`. Which then renders an icon of a "plus" symbol onto the page. This plus symbol is bound to a double-click handler which, which double-clicked, renders a modal dialog for creating a new instance of the model that `mymodel_instances` was created from.

This is great, but offers limited flexibility when creating front-end operator UX for projects.

This re-implementation is extremely similar, but instead of linking the modal dialog add-form to a plus icon, it allows the developer to wrap any arbitrary content. This could be as simple as text, but could also be a generic representation of the type of content that the operator wishes to create.

Very useful.

This has been submitted as a PR to the django CMS project, but, if accepted, wouldn't be available until version 3.1 or later. So, this code here is sort of like `from __future__ import ...` =)


## Installation

1. In your project, create a new app called "future", and add these two files in their appropriate places:

	````
	future
	    __init__.py
	    templates
	        cms
	            toolbar
	                plugin.html   <---- plugin.html goes here
	    templatetags
	        future_tags.py   <--- future_tags.py goes here here
	````

1. Next, add this new "future" app to your INSTALLED_APPS

1. Finally, since this implementation uses as much of the existing CMS code as possible, we need to tell your configuration to use *this* implmentation of plugin.html and not the normal one from your cms installation. So, in your settings add something like:

	````
	TEMPLATE_DIRS = (
	    os.path.join(PROJECT_PATH, "apps/future/templates"),   <---- add something like this before the existing line
	    os.path.join(PROJECT_PATH, "templates"),
	)
	````

## Usage

In your template, instead of using `{% render_model_add mymodel_instance %}`, use something like:

````
{% load future_tags ... %}
{% render_model_add_block mymodel_instance %}<div class="whatever"><img src="generic_sample.png"></div>{% endrender_model_add_block %}
````

future_tags.py

# -*- coding: utf-8 -*-

from django import template
from django.template.loader import render_to_string
from django.utils.safestring import mark_safe

from cms.templatetags.cms_tags import CMSEditableObject

from classytags.arguments import Argument
from classytags.core import Options

register = template.Library()


class CMSEditableObjectAddBlock(CMSEditableObject):
    """
    Templatetag that links arbitrary content to the addform for the specified
    model (based on the provided model instance).
    """
    name = 'render_model_add_block'
    options = Options(
        Argument('instance'),
        Argument('language', default=None, required=False),
        Argument('view_url', default=None, required=False),
        Argument('view_method', default=None, required=False),
        'as',
        Argument('varname', required=False, resolve=False),
        blocks=[('endrender_model_add_block', 'nodelist')],
    )

    def render_tag(self, context, **kwargs):
        """
        Renders the block and then inject the resulting HTML in the template
        context
        """
        context.push()
        template = self.get_template(context, **kwargs)
        data = self.get_context(context, **kwargs)
        data['content'] = mark_safe(kwargs['nodelist'].render(data))
        data['rendered_content'] = data['content']
        output = render_to_string(template, data)
        context.pop()
        if kwargs.get('varname'):
            context[kwargs['varname']] = output
            return ''
        else:
            return output

    def get_context(self, context, instance, language,
                    view_url, view_method, varname, nodelist):
        """
        Uses _get_empty_context and adds the `render_model_icon` variable.
        """
        extra_context = self._get_empty_context(context, instance, None,
                                                language, view_url, view_method,
                                                editmode=False)
        extra_context['render_model_add'] = True
        return extra_context
register.tag(CMSEditableObjectAddBlock)

plugin.html

{% spaceless %}{% load i18n l10n sekizai_tags static cms_tags %}

<div class="cms_plugin cms_plugin-{% if generic %}{{ generic.app_label }}-{{ generic.module_name }}-{% if attribute_name %}{{ attribute_name|slugify }}-{% endif %}{% endif %}{{ instance.pk|unlocalize }}{% if content %}{% elif render_model_icon %} cms_render_model_icon{% elif render_model %} cms_render_model{% elif render_model_block %} cms_render_model cms_render_model_block{% elif render_model_add %} cms_render_model_add{% endif %}">{% if content %}{{ content }}{% elif render_model_icon %}<img src="{% static 'cms/img/toolbar/render_model_placeholder.png' %}">{% elif render_model_add %}<img src="{% static 'cms/img/toolbar/render_model_placeholder.png' %}">{% else %}{{ rendered_content }}{% endif %}</div>

{% addtoblock "js" %}
<script>
(function($) {
// CMS.$ will be passed for $
$(document).ready(function () {
    new CMS.Plugin('cms_plugin-{% if generic %}{{ generic.app_label }}-{{ generic.module_name }}-{% if attribute_name %}{{ attribute_name|slugify }}-{% endif %}{% endif %}{{ instance.pk|unlocalize }}', {
        'type': {% if generic %}'generic'{% else %}'plugin'{% endif %},
        'page_language': '{{ LANGUAGE_CODE }}',
        'placeholder_id': '{{ instance.placeholder_id|unlocalize }}',
        'plugin_name': '{{ instance.get_plugin_name|default:"" }}',
        'plugin_type': '{{ instance.plugin_type }}',
        'plugin_id': '{{ instance.pk|unlocalize }}',
        'plugin_language': '{{ instance.language|default:"" }}',
        'plugin_parent': '{{ instance.parent_id|unlocalize }}',
        'plugin_order': '{{ instance.plugin_order }}',{% language request.toolbar.toolbar_language %}
        'plugin_breadcrumb': {{ instance.get_breadcrumb_json|default:"[]" }},
        'plugin_restriction': [{% for cls in allowed_child_classes %}"{{ cls }}"{% if not forloop.last %},{% endif %}{% endfor %}],
        'onClose': {% if refresh_page %}'REFRESH_PAGE'{% else %}{% if redirect_on_close %}'{{ redirect_on_close }}'{% else %}false{% endif %}{% endif %},
        'urls': {
            'add_plugin': '{% if add_url %}{{ add_url }}{% else %}{% cms_admin_url "cms_page_add_plugin" %}}{% endif %}',
            'edit_plugin': '{% if edit_url %}{{ edit_url }}{% elif instance %}{% cms_admin_url "cms_page_edit_plugin" instance.pk %}{% endif %}',
            'move_plugin': '{% if move_url %}{{ move_url }}{% else %}{% cms_admin_url "cms_page_move_plugin" %}{% endif %}',
            'delete_plugin': '{% if delete_url %}{{ delete_url }}{% elif instance %}{% cms_admin_url "cms_page_delete_plugin" instance.pk %}{% endif %}',
            'copy_plugin': '{% cms_admin_url "cms_page_copy_plugins" %}'
        } {% endlanguage %}
    });
});
})(CMS.$);
</script>{% endaddtoblock %}
{% endspaceless %}