================
TextLines Widget
================

The text lines widget allows you to store a sequence of textline. This sequence
is stored as a list or tuple. This depends on what you are using as sequence
type.

As for all widgets, the text lines widget must provide the new ``IWidget``
interface:

  >>> from zope.interface.verify import verifyClass
  >>> from z3c.form import interfaces
  >>> from z3c.form.browser import textlines

  >>> verifyClass(interfaces.IWidget, textlines.TextLinesWidget)
  True

The widget can be instantiated only using the request:

  >>> from z3c.form.testing import TestRequest
  >>> request = TestRequest()

  >>> widget = textlines.TextLinesWidget(request)

Before rendering the widget, one has to set the name and id of the widget:

  >>> widget.id = 'id'
  >>> widget.name = 'name'

We also need to register the template for at least the widget and request:

  >>> import zope.component
  >>> from zope.pagetemplate.interfaces import IPageTemplate
  >>> from z3c.form.testing import getPath
  >>> from z3c.form.widget import WidgetTemplateFactory

  >>> zope.component.provideAdapter(
  ...     WidgetTemplateFactory(getPath('textlines_input.pt'), 'text/html'),
  ...     (None, None, None, None, interfaces.ITextLinesWidget),
  ...     IPageTemplate, name=interfaces.INPUT_MODE)

If we render the widget we get an empty textarea widget:

  >>> print widget.render()
  <textarea id="id" name="name" class="textarea-widget"></textarea>

Adding some more attributes to the widget will make it display more:

  >>> widget.id = 'id'
  >>> widget.name = 'name'
  >>> widget.value = u'foo\nbar'

  >>> print widget.render()
  <textarea id="id" name="name" class="textarea-widget">foo
  bar</textarea>


TextLinesFieldWidget
--------------------

The field widget needs a field:

  >>> import zope.schema
  >>> text = zope.schema.List(
  ...     title=u'List',
  ...      value_type=zope.schema.TextLine())

  >>> widget = textlines.TextLinesFieldWidget(text, request)
  >>> widget
  <TextLinesWidget ''>

  >>> widget.id = 'id'
  >>> widget.name = 'name'
  >>> widget.value = u'foo\nbar'

  >>> print widget.render()
  <textarea id="id" name="name" class="textarea-widget">foo
  bar</textarea>


TextLinesFieldWidgetFactory
---------------------------

  >>> widget = textlines.TextLinesFieldWidgetFactory(text, text.value_type,
  ...     request)
  >>> widget
  <TextLinesWidget ''>

  >>> widget.id = 'id'
  >>> widget.name = 'name'
  >>> widget.value = u'foo\nbar'

  >>> print widget.render()
  <textarea id="id" name="name" class="textarea-widget">foo
  bar</textarea>