Source code for django_tables2.columns.linkcolumn

# coding: utf-8
from __future__ import absolute_import, unicode_literals

import warnings

from django.core.urlresolvers import reverse
from django.utils.html import format_html

from django_tables2.utils import Accessor, AttributeDict

from .base import Column, library


class BaseLinkColumn(Column):
    """
    The base for other columns that render links.

    Adds support for an ``a`` key in *attrs** which is added to the rendered
    ``<a href="...">`` tag.
    """
    def __init__(self, attrs=None, *args, **kwargs):
        kwargs['attrs'] = attrs
        super(BaseLinkColumn, self).__init__(*args, **kwargs)

    def render_link(self, uri, text, attrs=None):
        """
        Render a hyperlink.

        :param   uri: URI for the hyperlink
        :param  text: value wrapped in ``<a></a>``
        :param attrs: ``<a>`` tag attributes
        """
        attrs = AttributeDict(attrs if attrs is not None else
                              self.attrs.get('a', {}))
        attrs['href'] = uri

        return format_html('<a {attrs}>{text}</a>',
                           attrs=attrs.as_html(),
                           text=text)


@library.register
[docs]class LinkColumn(BaseLinkColumn): """ Renders a normal value as an internal hyperlink to another page. It's common to have the primary value in a row hyperlinked to the page dedicated to that record. The first arguments are identical to that of `~django.core.urlresolvers.reverse` and allows an internal URL to be described. If this argument is `None`, then `get_absolute_url`. (see Django references) will be used. The last argument *attrs* allows custom HTML attributes to be added to the rendered ``<a href="...">`` tag. :param viewname: See `~django.core.urlresolvers.reverse`. Or use `None` to use Model's `get_absolute_url` :param urlconf: See `~django.core.urlresolvers.reverse`. :param args: See `~django.core.urlresolvers.reverse`. ** :param kwargs: See `~django.core.urlresolvers.reverse`. ** :param current_app: See `~django.core.urlresolvers.reverse`. :param attrs: a `dict` of HTML attributes that are added to the rendered ``<input type="checkbox" .../>`` tag :param text: Either static text, or a callable. If set, this value will be used to render the text inside link instead of value (default) ** In order to create a link to a URL that relies on information in the current row, `.Accessor` objects can be used in the *args* or *kwargs* arguments. The accessor will be resolved using the row's record before `~django.core.urlresolvers.reverse` is called. Example: .. code-block:: python # models.py class Person(models.Model): name = models.CharField(max_length=200) # urls.py urlpatterns = patterns('', url('people/(\d+)/', views.people_detail, name='people_detail') ) # tables.py from django_tables2.utils import A # alias for Accessor class PeopleTable(tables.Table): name = tables.LinkColumn('people_detail', args=[A('pk')]) In order to override the text value (i.e. <a ... >text</a>) consider the following example: .. code-block:: python # tables.py from django_tables2.utils import A # alias for Accessor class PeopleTable(tables.Table): name = tables.LinkColumn('people_detail', text='static text', args=[A('pk')]) age = tables.LinkColumn('people_detail', text=lambda record: record.name, args=[A('pk')]) In the first example, a static text would be rendered ('static text') In the second example, you can specify a callable which accepts a record object (and thus can return anything from it) In addition to *attrs* keys supported by `.Column`, the following are available: - *a* -- ``<a>`` elements in ``<td>``. """ def __init__(self, viewname=None, urlconf=None, args=None, kwargs=None, current_app=None, attrs=None, text=None, **extra): super(LinkColumn, self).__init__(attrs, **extra) self.viewname = viewname self.urlconf = urlconf self.args = args self.kwargs = kwargs self.current_app = current_app self.text_value = text
[docs] def compose_url(self, record, *args, **kwargs): '''Compose the url if the column is constructed with a viewname.''' if self.viewname is None: if not hasattr(record, 'get_absolute_url'): raise TypeError('if viewname=None, record must define a get_absolute_url') return record.get_absolute_url() def resolve_if_accessor(val): return val.resolve(record) if isinstance(val, Accessor) else val viewname = resolve_if_accessor(self.viewname) # Collect the optional arguments for django's reverse() params = {} if self.urlconf: params['urlconf'] = resolve_if_accessor(self.urlconf) if self.args: params['args'] = [resolve_if_accessor(a) for a in self.args] if self.kwargs: params['kwargs'] = {key: resolve_if_accessor(val) for key, val in self.kwargs.items()} if self.current_app: params['current_app'] = resolve_if_accessor(self.current_app) return reverse(viewname, **params)
def render(self, value, record, bound_column): text_value = value if self.text_value: text_value = self.text_value if callable(text_value): text_value = text_value(record) return self.render_link(self.compose_url(record, bound_column), text=text_value)
@library.register class RelatedLinkColumn(LinkColumn): ''' Render a link to a related object using related object's ``get_absolute_url`` ''' def compose_url(self, record, bound_column): accessor = self.accessor if self.accessor else Accessor(bound_column) return accessor.resolve(record).get_absolute_url()