zc.form 3.0

Changes

CombinationWidget

The combinationwidget collects two or more subfields to provide a convenient way to specify a sequence of values.

Rendering the widget returns a table with the subfields:

>>> from zc.form.browser.combinationwidget import (
...     CombinationWidget, CombinationDisplayWidget, default_template)
>>> from zope import component, interface
>>> component.provideAdapter(default_template, name='default')
>>> from zc.form.field import Combination, OrderedCombinationConstraint
>>> from zope.schema import Int
>>> from zope.schema.interfaces import IInt
>>> from zope.publisher.interfaces.browser import IBrowserRequest
>>> from zope.formlib.interfaces import IInputWidget
>>> from zope.formlib.textwidgets import IntWidget
>>> component.provideAdapter(
...     IntWidget, (IInt, IBrowserRequest), IInputWidget)
>>> from zope import interface
>>> class IDemo(interface.Interface):
...     acceptable_count = Combination(
...         (Int(title=u'Minimum', required=True, min=0),
...          Int(title=u'Maximum', required=False)),
...         title=u'Acceptable Count',
...         required=False,
...         constraints=(OrderedCombinationConstraint(),))
...
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> widget = CombinationWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.loadValueFromRequest() # None
>>> print(widget())
<input type='hidden' name='field.acceptable_count-marker' value='x' />
<table class="combinationFieldWidget">
  <tr>
    <td class="label">
      <label for="field.acceptable_count.combination_00">
        <span class="required">*</span><span>Minimum</span>
      </label>
    </td>
    <td class="field">
      <div class="widget"><input class="textType"
        id="field.acceptable_count.combination_00"
        name="field.acceptable_count.combination_00" size="10" type="text"
        value=""  />
      </div>
    </td>
  </tr>
  <tr>
    <td class="label">
      <label for="field.acceptable_count.combination_01">
        <span>Maximum</span>
      </label>
    </td>
    <td class="field">
      <div class="widget"><input class="textType"
        id="field.acceptable_count.combination_01"
        name="field.acceptable_count.combination_01" size="10" type="text"
        value=""  />
      </div>
    </td>
  </tr>
</table>

Setting the appropriate values in the Request lets the widget correctly read the specified value:

>>> request.form['field.acceptable_count-marker'] = 'x'
>>> request.form['field.acceptable_count.combination_00'] = '10'
>>> request.form['field.acceptable_count.combination_01'] = ''
>>> widget = CombinationWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.getInputValue()
(10, None)
>>> print(widget())
<...
...<input class="textType" id="field.acceptable_count.combination_00"
          name="field.acceptable_count.combination_00" size="10" type="text"
          value="10" />...
...<input class="textType" id="field.acceptable_count.combination_01"
          name="field.acceptable_count.combination_01" size="10" type="text"
          value="" />...

The field is fine with empty values, because it is not required:

>>> request.form['field.acceptable_count-marker'] = 'x'
>>> request.form['field.acceptable_count.combination_00'] = ''
>>> request.form['field.acceptable_count.combination_01'] = ''
>>> widget = CombinationWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.getInputValue() # None
>>> print(widget())
<...
...<input class="textType" id="field.acceptable_count.combination_00"
          name="field.acceptable_count.combination_00" size="10" type="text"
          value="" />...
...<input class="textType" id="field.acceptable_count.combination_01"
          name="field.acceptable_count.combination_01" size="10" type="text"
          value="" />...
>>> bool(widget.error())
False
>>> bool(widget.widgets[0].error())
False

If the optional value is filled in and the required one is not, though, there are errors:

>>> request.form['field.acceptable_count-marker'] = 'x'
>>> request.form['field.acceptable_count.combination_00'] = ''
>>> request.form['field.acceptable_count.combination_01'] = '10'
>>> widget = CombinationWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.getInputValue()
Traceback (most recent call last):
WidgetInputError: ('acceptable_count', u'Acceptable Count',
WidgetInputError('combination_00', u'Minimum',
RequiredMissing('combination_00')))
>>> import zope.formlib.interfaces
>>> import zope.publisher.interfaces.browser
>>> @interface.implementer(zope.formlib.interfaces.IWidgetInputErrorView)
... @component.adapter(zope.formlib.interfaces.WidgetInputError,
...     zope.publisher.interfaces.browser.IBrowserRequest)
... class SnippetView(object):
...
...     def __init__(self, context, request):
...         self.context = context
...         self.request = request
...     def snippet(self):
...         return self.context.doc()
...
>>> component.provideAdapter(SnippetView)
>>> print(widget())
<...
...<input class="textType" id="field.acceptable_count.combination_00"
          name="field.acceptable_count.combination_00" size="10"
          type="text" value="" />...
...Required input is missing...
...<input class="textType" id="field.acceptable_count.combination_01"
          name="field.acceptable_count.combination_01" size="10"
          type="text" value="10" />...
>>> print(widget.error())
Required input is missing.
>>> print(widget.widgets[0].error())
Required input is missing.

Similarly, if the field’s constraints are not met, the widget shows errors:

>>> request.form['field.acceptable_count-marker'] = 'x'
>>> request.form['field.acceptable_count.combination_00'] = '20'
>>> request.form['field.acceptable_count.combination_01'] = '10'
>>> widget = CombinationWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.getInputValue()
Traceback (most recent call last):
WidgetInputError: ('acceptable_count', u'Acceptable Count',
MessageValidationError(u'${minimum} ...
>>> print(widget())
<...
...input class="textType" id="field.acceptable_count.combination_00"
          name="field.acceptable_count.combination_00" size="10"
          type="text" value="20" />...
...<input class="textType" id="field.acceptable_count.combination_01"
          name="field.acceptable_count.combination_01" size="10"
          type="text" value="10" />...
>>> print(widget.error())
${minimum} must be less than or equal to ${maximum}.

There’s also a display version of the widget:

>>> request = TestRequest()
>>> from zope.formlib.widget import DisplayWidget
>>> from zope.formlib.interfaces import IDisplayWidget
>>> component.provideAdapter(
...     DisplayWidget, (IInt, IBrowserRequest), IDisplayWidget)
>>> widget = CombinationDisplayWidget(IDemo['acceptable_count'], request)
>>> widget.setPrefix('field')
>>> widget.setRenderedValue(('10', '2'))
>>> print(widget())
<input type='hidden' name='field.acceptable_count-marker' value='x' />
    <table class="combinationFieldWidget">
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_00">
                  <span>Minimum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">10
            </div>
          </td>
      </tr>
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_01">
                  <span>Maximum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">2
            </div>
          </td>
      </tr>
    </table>

In case of a wrong amount of parameters, the missing_value is used:

>>> field = IDemo['acceptable_count']
>>> field.missing_value=('23', '42')
>>> widget = CombinationDisplayWidget(field, request)
>>> widget.setPrefix('field')
>>> widget.setRenderedValue(('10', '2', '3'))
>>> print(widget())
<input type='hidden' name='field.acceptable_count-marker' value='x' />
    <table class="combinationFieldWidget">
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_00">
                  <span>Minimum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">23
            </div>
          </td>
      </tr>
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_01">
                  <span>Maximum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">42
            </div>
          </td>
      </tr>
    </table>

In case the parameter is not a sequence, the missing_value is used:

>>> widget = CombinationDisplayWidget(field, request)
>>> widget.setPrefix('field')
>>> widget.setRenderedValue(10)
>>> print(widget())
<input type='hidden' name='field.acceptable_count-marker' value='x' />
    <table class="combinationFieldWidget">
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_00">
                  <span>Minimum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">23
            </div>
          </td>
      </tr>
      <tr>
              <td class="label">
                <label for="field.acceptable_count.combination_01">
                  <span>Maximum</span>
                </label>
              </td>
          <td class="field">
            <div class="widget">42
            </div>
          </td>
      </tr>
    </table>

The order of label and field are inverted in case of boolean:

>>> request = TestRequest()
>>> from zope.schema import Bool
>>> from zope.schema.interfaces import IBool
>>> from zope.formlib.boolwidgets import CheckBoxWidget
>>> from zope.formlib.widget import DisplayWidget
>>> from zope.formlib.interfaces import IDisplayWidget
>>> component.provideAdapter(
...     CheckBoxWidget, (IBool, IBrowserRequest), IInputWidget)
>>> class IBoolDemo(interface.Interface):
...     choices = Combination(
...         (Bool(title=u'first'),
...          Bool(title=u'second')),
...         title=u'Choices',
...         required=False,)

>>> widget = CombinationWidget(IBoolDemo['choices'], request)
>>> widget.setPrefix('field')
>>> print(widget())
<input type='hidden' name='field.choices-marker' value='x' />
    <table class="combinationFieldWidget">
      <tr>
            <td></td>
          <td class="field">
            <div class="widget"><input class="hiddenType" id="field.choices.combination_00.used" name="field.choices.combination_00.used" type="hidden" value="" /> <input class="checkboxType" id="field.choices.combination_00" name="field.choices.combination_00" type="checkbox" value="on"  />
              <span>first</span>
            </div>
          </td>
      </tr>
      <tr>
            <td></td>
          <td class="field">
            <div class="widget"><input class="hiddenType" id="field.choices.combination_01.used" name="field.choices.combination_01.used" type="hidden" value="" /> <input class="checkboxType" id="field.choices.combination_01" name="field.choices.combination_01" type="checkbox" value="on"  />
              <span>second</span>
            </div>
          </td>
      </tr>
    </table>

Most Recently Used (MRU) Source Widget

The MRU widget keeps track of the last few values selected (on a per-principal basis) and allows quickly selecting from that list instead of using a query interface.

We can see the widget in action by using a custom form. Let’s define a schema for the form that uses a source:

>>> import zope.interface
>>> import zope.schema

>>> class IDemo(zope.interface.Interface):
...
...     color = zope.schema.Choice(
...         title=u"Color",
...         description=u"My favorite color",
...         source=AvailableColors,
...         )

And then a class that implements the interface:

>>> @zope.interface.implementer(IDemo)
... class Demo(object):
...
...     color = None

We’ll need a form that uses this schema:

>>> import zope.formlib.form

>>> class DemoInput(zope.formlib.form.EditForm):
...     actions = ()
...     form_fields = zope.formlib.form.fields(IDemo)

By rendering the form we can see that there are no MRU items to choose from (because this principal has never visited this form before) and the query interface is displayed:

>>> import zope.publisher.browser
>>> import zope.security.interfaces
>>> import zope.security.management
>>> import zope.component.hooks

>>> @zope.interface.implementer(zope.security.interfaces.IPrincipal)
... class DummyPrincipal(object):
...
...     id = "someuser"
...     title = "Some User's Name"
...     description = "A User"

Note that we need to use the special resourcelibrary request. We’re hacking together the TestRequest and the resourcelibrary request here; when we switch to TestBrowser we can remove this oddity.

>>> import zc.resourcelibrary.publication
>>> class TestRequest(zope.publisher.browser.TestRequest,
...                   zc.resourcelibrary.publication.Request):
...     def _createResponse(self):
...         return zc.resourcelibrary.publication.Request._createResponse(
...             self)
...

>>> request = TestRequest()
>>> principal = DummyPrincipal()
>>> request.setPrincipal(principal)
>>> zope.security.management.newInteraction(request)

>>> oldsite = zope.component.hooks.getSite()
>>> zope.component.hooks.setSite(getRootFolder())

Now we can use an instance of our demo object to see that the form pulls the possible values from the vocabulary we’ve defined above:

>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<div class="queries"...>
<div class="query"...>
  <div class="queryinput"...>
    <query view for colors>
  </div> <!-- queryinput -->
</div> <!-- query -->
</div> <!-- queries -->
...

Note that the select box of MRU values isn’t in the output, because the user has never selected a value before:

>>> '<select name="form.color">' not in form()
True

Now, we can select one of the values:

>>> zope.security.management.endInteraction()

>>> request = TestRequest()
>>> request.form = {
...     'form.color.query.selection': 'red_token',
...     'form.color.query.apply': 'Apply',
...     'form.color.displayed': '',
...     }
>>> request.setPrincipal(principal)

>>> zope.security.management.newInteraction(request)

Process the request and the list of MRU values is in the form:

>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="red_token" selected="selected">Red</option>
</select>
...

And the query view is hidden because we have an MRU list:

>>> print(form())
<...
<input type="hidden" name="form.color.queries.visible" ... value="no">
...

If we select another value…:

>>> request = TestRequest()
>>> request.form = {
...     'form.color.query.selection': 'green_token',
...     'form.color.query.apply': 'Apply',
...     'form.color.displayed': '',
...     }
>>> request.setPrincipal(principal)

…and process the request, the list of MRU values includes the new one, at the top, and it is selected:

>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="green_token" selected="selected">Green</option>
  <option value="red_token">Red</option>
</select>
...

If we request a value not in the source everything stays the same, but nothing is selected:

>>> request = TestRequest()
>>> request.form = {
...     'form.color.query.selection': 'blue_token',
...     'form.color.query.apply': 'Apply',
...     'form.color.displayed': '',
...     }
>>> request.setPrincipal(principal)
>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="green_token">Green</option>
  <option value="red_token">Red</option>
</select>
...

We can make the query visible:

>>> request = TestRequest()
>>> request.form = {
...     'form.color.query.selection': 'red_token',
...     'form.color.query.apply': 'Apply',
...     'form.color.queries.visible': 'yes',
...     'form.color.query.search': 'yes',
...     'form.color.query.searchstring': 'red',
...     'form.color.displayed': '',
...     }
>>> request.setPrincipal(principal)
>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="red_token" selected="selected">Red</option>
  <option value="green_token">Green</option>
</select>
...
<select name="form.color.query.selection">
<option value="red_token">Red</option>
</select>
<input type="submit" name="form.color.query.apply" value="Apply" />
...

It is not shown if the query is not applied:

>>> request = TestRequest()
>>> request.form = {
...     'form.color.query.selection': 'red_token',
...     'form.color.queries.visible': 'yes',
...     'form.color.query.search': 'yes',
...     'form.color.query.searchstring': 'red',
...     'form.color.displayed': '',
...     }
>>> request.setPrincipal(principal)
>>> form = DemoInput(Demo(), request)
>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="red_token">Red</option>
  <option value="green_token">Green</option>
</select>
...
<select name="form.color.query.selection">
<option value="red_token">Red</option>
</select>
<input type="submit" name="form.color.query.apply" value="Apply" />
...

Tokens in the annotation of the principal are ignored if they are not in the source:

>>> from zope.annotation.interfaces import IAnnotations
>>> annotations = IAnnotations(principal)
>>> annotation = annotations.get('zc.form.browser.mruwidget')
>>> tokens = annotation.get('form.color')
>>> tokens.append('black_token')
>>> tokens
['red_token', 'green_token', 'black_token']

>>> print(form())
<...
<select name="form.color" id="form.color">
  <option value="red_token">Red</option>
  <option value="green_token">Green</option>
</select>
...
<select name="form.color.query.selection">
<option value="red_token">Red</option>
</select>
<input type="submit" name="form.color.query.apply" value="Apply" />
...

Clean up a bit:

>>> zope.security.management.endInteraction()
>>> zope.component.hooks.setSite(oldsite)