Nik*_*ntz 5 python forms web-applications jinja2 wtforms
我有一个选择字段，其中某些元素已褪色和禁用，我想用 WTForms 呈现这些元素：
<select name="cg" id="cat" class="search_category">
<option value='' >{% trans %}All{% endtrans %}</option>
<option value='' style='background-color:#dcdcc3' id='cat1' disabled="disabled">-- {% trans %}VEHICLES{% endtrans %} --</option>
<option value='2' {% if "2" == cg %} selected="selected" {% endif %} id='cat2' >{% trans %}Cars{% endtrans %}</option>
<option value='3' {% if "3" == cg %} selected="selected" {% endif %} id='cat3' >{% trans %}Motorcycles{% endtrans %}</option>
<option value='4' {% if "4" == cg %} selected="selected" {% endif %} id='cat4' >{% trans %}Accessories & Parts{% endtrans %}</option>
...
我有一个有效的表单类，我开始实现本地化类别变量，但我不知道如何制作将褪色 ( background-color:#dcdcc3) 和禁用属性呈现给选项元素的小部件 (?) ：
class AdForm(Form):
my_choices = [('1', _('VEHICLES')), ('2', _('Cars')), ('3', _('Bicycles'))]
name = TextField(_('Name'), [validators.Required(message=_('Name is required'))], widget=MyTextInput())
title = TextField(_('title'), [validators.Required(message=_('Subject is required'))], widget=MyTextInput())
text = TextAreaField(_('Text'),[validators.Required(message=_('Text is required'))], widget=MyTextArea())
phonenumber = TextField(_('Phone number'))
phoneview = BooleanField(_('Display phone number on site'))
price = TextField(_('Price'),[validators.Regexp('\d', message=_('This is not an integer number, please see the example and try again')),validators.Optional()] )
password = PasswordField(_('Password'),[validators.Optional()], widget=PasswordInput())
email = TextField(_('Email'), [validators.Required(message=_('Email is required')), validators.Email(message=_('Your email is invalid'))], widget=MyTextInput())
category = SelectField(choices = my_choices, default = '1')
def validate_name(form, field):
if len(field.data) > 50:
raise ValidationError(_('Name must be less than 50 characters'))
def validate_email(form, field):
if len(field.data) > 60:
raise ValidationError(_('Email must be less than 60 characters'))
def validate_price(form, field):
if len(field.data) > 8:
raise ValidationError(_('Price must be less than 9 integers'))
我可以使用上面的变量类别来呈现类别的选择。我还想启用特殊渲染，即禁用元素和褪色背景。你能告诉我我该怎么做吗？
谢谢
当尝试从答案中添加禁用属性的解决方案时，我收到此错误消息：
Trace:
Traceback (most recent call last):
File "/media/Lexar/montao/lib/webapp2/webapp2.py", line 545, in dispatch
return method(*args, **kwargs)
File "/media/Lexar/montao/montaoproject/i18n.py", line 438, in get
current_user=self.current_user,
File "/media/Lexar/montao/montaoproject/main.py", line 469, in render_jinja
self.response.out.write(template.render(data))
File "/media/Lexar/montao/montaoproject/jinja2/environment.py", line 894, in render
return self.environment.handle_exception(exc_info, True)
File "/media/Lexar/montao/montaoproject/templates/insert_jinja.html", line 221, in top-level template code
{{ form.category|safe }}
ValueError: need more than 2 values to unpack
我试过的代码是：
from wtforms.widgets import html_params
class SelectWithDisable(object):
"""
Renders a select field.
If `multiple` is True, then the `size` property should be specified on
rendering to make the field useful.
The field must provide an `iter_choices()` method which the widget will
call on rendering; this method must yield tuples of
`(value, label, selected, disabled)`.
"""
def __init__(self, multiple=False):
self.multiple = multiple
def __call__(self, field, **kwargs):
kwargs.setdefault('id', field.id)
if self.multiple:
kwargs['multiple'] = 'multiple'
html = [u'<select %s>' % html_params(name=field.name, **kwargs)]
for val, label, selected, disabled in field.iter_choices():
html.append(self.render_option(val, label, selected, disabled))
html.append(u'</select>')
return HTMLString(u''.join(html))
@classmethod
def render_option(cls, value, label, selected, disabled):
options = {'value': value}
if selected:
options['selected'] = u'selected'
if disabled:
options['disabled'] = u'disabled'
return HTMLString(u'<option %s>%s</option>' % (html_params(**options), escape(unicode(label))))
class SelectFieldWithDisable(SelectField):
widget = SelectWithDisable()
def iter_choices(self):
for value, label, selected, disabled in self.choices:
yield (value, label, selected, disabled, self.coerce(value) == self.data)
class AdForm(Form):
my_choices = [('1', _('VEHICLES')), ('2', _('Cars')), ('3', _('Motorcycles'))]
nouser = HiddenField(_('No user'))
name = TextField(_('Name'), [validators.Required(message=_('Name is required'))], widget=MyTextInput())
title = TextField(_('Subject'), [validators.Required(message=_('Subject is required'))], widget=MyTextInput())
text = TextAreaField(_('Text'),[validators.Required(message=_('Text is required'))], widget=MyTextArea())
phonenumber = TextField(_('Phone number'))
phoneview = BooleanField(_('Display phone number on site'))
price = TextField(_('Price'),[validators.Regexp('\d', message=_('This is not an integer number, please see the example and try again')),validators.Optional()] )
password = PasswordField(_('Password'),validators=[RequiredIf('nouser', message=_('Password is required'))], widget=MyPasswordInput())
email = TextField(_('Email'), [validators.Required(message=_('Email is required')), validators.Email(message=_('Your email is invalid'))], widget=MyTextInput())
category = SelectFieldWithDisable(choices = my_choices)
def validate_name(form, field):
if len(field.data) > 50:
raise ValidationError(_('Name must be less than 50 characters'))
def validate_email(form, field):
if len(field.data) > 60:
raise ValidationError(_('Email must be less than 60 characters'))
def validate_price(form, field):
if len(field.data) > 8:
raise ValidationError(_('Price must be less than 9 integers'))
我想我必须在某处设置“禁用”属性，但在哪里？
这比我想象的要棘手。wtforms 邮件列表上也有一个建议的解决方案，但我也无法让它工作（一些关于无效语法的小错误，无法从 wtforms 导入 ecscape 所以我采取的行动是从 hg 存储库更新我的 wtforms如果那里发生了重要的变化。
从这里的答案我要么得到，Need more than 2 values to unpack要么ValueError: too many values to unpack我似乎无法正确理解。在我的模板中，我试图呈现的是
{{ form.category }}
我的表单类是
class AdForm(Form):
my_choices = [('1', _('VEHICLES'), False, True), ('2', _('Cars'), False, False), ('3', _('Motorcycles'), False, False)]
...
category = SelectFieldWithDisable(choices = my_choices)
加上我从这里得到的附加课程：
class SelectWithDisable(object):
"""
Renders a select field.
If `multiple` is True, then the `size` property should be specified on
rendering to make the field useful.
The field must provide an `iter_choices()` method which the widget will
call on rendering; this method must yield tuples of
`(value, label, selected, disabled)`.
"""
def __init__(self, multiple=False):
self.multiple = multiple
def __call__(self, field, **kwargs):
kwargs.setdefault('id', field.id)
if self.multiple:
kwargs['multiple'] = 'multiple'
html = [u'<select %s>' % html_params(name=field.name, **kwargs)]
for val, label, selected, disabled in field.iter_choices():
html.append(self.render_option(val, label, selected, disabled))
html.append(u'</select>')
return HTMLString(u''.join(html))
@classmethod
def render_option(cls, value, label, selected, disabled):
options = {'value': value}
if selected:
options['selected'] = u'selected'
if disabled:
options['disabled'] = u'disabled'
return HTMLString(u'<option %s>%s</option>' % (html_params(**options), escape(unicode(label))))
class SelectFieldWithDisable(SelectField):
widget = SelectWithDisable()
def iter_choices(self):
for value, label, selected, disabled in self.choices:
yield (value, label, selected, disabled, self.coerce(value) == self.data)
编辑：
如果您希望始终在禁用某些选项的情况下渲染字段，则必须创建自己的自定义小部件和字段以提供给渲染器。
当前渲染器仅在其选择元组中采用三个选项：(value, name, selected)。
您需要修改它以接受第四个可选元素：disabled。
基于 wtforms.widget 中的 Select 类：
class SelectWithDisable(object):
"""
Renders a select field.
If `multiple` is True, then the `size` property should be specified on
rendering to make the field useful.
The field must provide an `iter_choices()` method which the widget will
call on rendering; this method must yield tuples of
`(value, label, selected, disabled)`.
"""
def __init__(self, multiple=False):
self.multiple = multiple
def __call__(self, field, **kwargs):
kwargs.setdefault('id', field.id)
if self.multiple:
kwargs['multiple'] = 'multiple'
html = [u'<select %s>' % html_params(name=field.name, **kwargs)]
for val, label, selected, disabled in field.iter_choices():
html.append(self.render_option(val, label, selected, disabled))
html.append(u'</select>')
return HTMLString(u''.join(html))
@classmethod
def render_option(cls, value, label, selected, disabled):
options = {'value': value}
if selected:
options['selected'] = u'selected'
if disabled:
options['disabled'] = u'disabled'
return HTMLString(u'<option %s>%s</option>' % (html_params(**options), escape(unicode(label))))
然后根据wtforms.fields中的代码，对已经存在的SelectField进行子类化
class SelectFieldWithDisable(SelectFiel):
widget = widgets.SelectWithDisable()
def iter_choices(self):
for value, label, selected, disabled in self.choices:
yield (value, label, selected, disabled, self.coerce(value) == self.data)
注意：这未经测试，甚至没有运行 Python 代码，但考虑到问题和来自 WTFORMS 的底层代码，这是一个非常快速的破解。但它应该给你足够的领先优势以及之前的答案来完全控制这个领域。
使用 CSS 和 JavaScript 来控制页面上呈现的元素。
在您使用的任何模板渲染系统中（我使用的是 Flask、jinja 和 wtforms），您都会渲染 elemen 并在渲染时提供 id 或 class 属性。（我只是打印form.select_field_variable_name）
然后生成 CSS 文件来控制样式并使用 JavaScript 来控制某些元素的自定义禁用等。
编辑：
如果你有：
<select id=selector>
<option id=value1 value=1>Bananas</option>
<option id=value2 value=2>Corn</option>
<option id=value3 value=3>Lolcats</option>
</select>
您可以使用以下方法应用背景颜色：
<style>
#selector {background-color: #beef99}
</style>
您可以使用以下命令启用/禁用：
<script>
option = document.getElementById('value3')
option.disabled = true
</script>
等等等等等等
使用 WTForms 小部件渲染元素后，就像所有 HTML 元素一样，您应该使用 CSS 和 JavaScript 来设计和控制元素的任何动态部分