Using FieldList and FormField

问题

We have the following forms and we are trying to create list of GroupRoleForms for each group.

class FullNameMixIn():
    full_name = TextField(
        'Full name', [
            validators.required(message=u"Full name is required")
        ])

class GroupRoleForm(Form):
    group =BooleanField('Group', default=False)
    role = SelectField(
            'Role',choices=[
            ("none", "----------"), 
            ('approver', 'Approver'),
            ('editor', 'Editor')
            ])

class AdminEditUserForm(Form, FullNameMixIn):
    group_roles = FieldList(FormField(GroupRoleForm))

How can we create a AdminEditUserForm instance that contains a pre-populated list of GroupRoleForms?

At the moment we are trying to do it this way:

form = forms.AdminEditUserForm()
for group in  company.groups:
    group_role_form = forms.GroupRoleForm()
    group_role_form.group.label =  group.name
    group_role_form.group.name = group.id
    form.group_roles.append_entry(group_role_form)
return dict(edit_user_form = form )

回答1:

Explanation

In your data or formdata keyword arguments for the Form you just need an dictionary with a key that matches the FieldList subfield that contains an iterable. The items in that iterable need in turn have items w/ attributes that match with FieldList's list of fields.

If you follow the example below I get nested Forms that are pre-populated just fine.

The Code

from collections import namedtuple

from wtforms import validators
from wtforms import Form
from wtforms import SelectField
from wtforms import BooleanField
from wtforms import TextField
from wtforms import FieldList
from wtforms import FormField

from webob.multidict import MultiDict

# OP's Code
class FullNameMixIn():
    full_name = TextField(
        'Full name', [
            validators.required(message=u"Full name is required")
        ])

class GroupRoleForm(Form):
    group =BooleanField('Group', default=False)
    role = SelectField(
            'Role',choices=[
            ("none", "----------"), 
            ('approver', 'Approver'),
            ('editor', 'Editor')
            ])

class AdminEditUserForm(Form, FullNameMixIn):
    group_roles = FieldList(FormField(GroupRoleForm))

# create some groups
Group = namedtuple('Group', ['group', 'role'])
g1 = Group('group-1', 'none')
g2 = Group('group-2', 'none')

# drop them in a dictionary 
data_in={'group_roles': [g1, g2]}

# Build form 
test_form = AdminEditUserForm(data=MultiDict(data_in))

# test print
print test_form.group_roles()

The Rendered HTML(Truncated)

<ul id="group_roles">
   <li>
      <label for="group_roles-0">Group Roles-0</label> 
      <table id="group_roles-0">
         <tr>
            <th><label for="gr
               oup_roles-0-group">Group</label></th>
            <td><input checked id="group_roles-0-group" name="group_roles-0-group" type="checkbox" value="y"><
               /td>
         </tr>
         <tr>
            <th><label for="group_roles-0-role">Role</label></th>
            <td>
               <select id="group_roles-0-role" name="group_roles-0-role">
                  <option
                     selected value="none">----------</option>
                  <option value="approver">Approver</option>
                  <option value="editor">Editor</option>
               </select>
            </td
               >
         </tr>
      </table>
   </li>
   <li>
      <label for="group_roles-1">Group Roles-1</label> 
      <table id="group_roles-1">
         <tr>
            <th><label for="group_roles-1-gro
               up">Group</label></th>
            <td><input checked id="group_roles-1-group" name="group_roles-1-group" type="checkbox" value="y"></td>
         </tr>
         <tr>
            <t
               h>
            <label for="group_roles-1-role">Role</label></th>
            <td>
               <select id="group_roles-1-role" name="group_roles-1-role">
                  <option selected value
                     ="none">----------</option>
                  <option value="approver">Approver</option>
                  <option value="editor">Editor</option>
               </select>
            </td>
         </tr>
      </table>
      <
      /li>
</ul>

...

回答2:

I'm not familiar with these packages but I'll take a stab:

class AdminEditUserForm(Form, FullNameMixIn):
    def __init__(self, groups):
        super(AdminEditUserForm, self).__init__()
        self.group_roles = FieldList(FormField(GroupRoleForm))
        for group in groups:
            self.group.label = group.name
            self.group.name = group.id
            self.group_roles.append_entry(self.group)  
            # If this doesn't create a copy of the GroupRoleForm 
            # superclass in group_roles, then you need a method to do it
            self.__clear_group()

    def __clear_group(self):
        # copy GroupRoleForm object, if needed
        # delete GroupRoleForm object
        ...

then you can call it like so:

form = forms.AdminEditUserForm(company.groups)

来源：https://stackoverflow.com/questions/12040688/using-fieldlist-and-formfield