Widget template directive

Show how we can use the widget template directive. Register the meta configuration for the directive.

>>> import sys
>>> from zope.configuration import xmlconfig
>>> import z3c.form
>>> context = xmlconfig.file('meta.zcml', z3c.form)

We need a custom widget template

>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> file = os.path.join(temp_dir, 'widget.pt')
>>> open(file, 'w').write('''
... <input type="text" id="" name="" value="" size=""
...        tal:attributes="id view/id;
...                        name view/name;
...                        size view/size;
...                        value view/value;" />
... ''')

and a interface

>>> import zope.interface
>>> from z3c.form import interfaces
>>> class IMyWidget(interfaces.IWidget):
...     """My widget interface."""

and a widget class:

>>> from z3c.form.testing import TestRequest
>>> from z3c.form.browser import text
>>> class MyWidget(text.TextWidget):
...     zope.interface.implements(IMyWidget)
>>> request = TestRequest()
>>> myWidget = MyWidget(request)

Make them available under the fake package custom:

>>> sys.modules['custom'] = type(
...     'Module', (),
...     {'IMyWidget': IMyWidget})()

and register them as a widget template within the z3c:widgetTemplate directive:

>>> context = xmlconfig.string("""
... <configure
...     xmlns:z3c="http://namespaces.zope.org/z3c">
...   <z3c:widgetTemplate
...       template="%s"
...       widget="custom.IMyWidget"
...       />
... </configure>
... """ % file, context=context)

Let's get the template

>>> import zope.component
>>> from z3c.template.interfaces import IPageTemplate
>>> template = zope.component.queryMultiAdapter((None, request, None, None,
...     myWidget), interface=IPageTemplate, name='input')

and check them:

>>> template
<zope.app.pagetemplate.viewpagetemplatefile.ViewPageTemplateFile ...>

Let's use the template within the widget.

>>> print template(myWidget)
<input type="text" value="" />

We normly render the widget which returns the registered template.

>>> print myWidget.render()
<input type="text" value="" />

If the template does not exist, then the widget directive should fail immediately:

>>> unknownFile = os.path.join(temp_dir, 'unknown.pt')
>>> context = xmlconfig.string("""
... <configure
...     xmlns:z3c="http://namespaces.zope.org/z3c">
...   <z3c:widgetTemplate
...       template="%s"
...       widget="custom.IMyWidget"
...       />
... </configure>
... """ % unknownFile, context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "<string>", line 4.2-7.8
    ConfigurationError: ('No such file', '...unknown.pt')

Cleanup

Now we need to clean up the custom module.

>>> del sys.modules['custom']