Django - 如何扩展表单？

Question

我是姜戈的新手。我已经安装了一个位于“python2.6/site-packages/haystack”中的外部应用程序。这个外部应用程序有“通用表单”，但我需要添加一个不属于“通用表单”的 CSS 类。

如何在我自己的应用程序中将“forms.py”“class FacetedModelSearchForm”从“通用表单”扩展到“forms.py”？

这是来自“通用表单”的代码

class SearchForm(forms.Form):
    q = forms.CharField(required=False, label=_('Search'))

    def __init__(self, *args, **kwargs):
        self.searchqueryset = kwargs.pop('searchqueryset', None)
        self.load_all = kwargs.pop('load_all', False)

        if self.searchqueryset is None:
            self.searchqueryset = SearchQuerySet()

        super(SearchForm, self).__init__(*args, **kwargs)

    def no_query_found(self):
        """
        Determines the behavior when no query was found.
        By default, no results are returned (``EmptySearchQuerySet``).
        Should you want to show all results, override this method in your
        own ``SearchForm`` subclass and do ``return self.searchqueryset.all()``.
        """
        return EmptySearchQuerySet()

    def search(self):
        if not self.is_valid():
            return self.no_query_found()

        if not self.cleaned_data.get('q'):
            return self.no_query_found()

        sqs = self.searchqueryset.auto_query(self.cleaned_data['q'])

        if self.load_all:
            sqs = sqs.load_all()

        return sqs

    def get_suggestion(self):
    if not self.is_valid():
        return None

    return self.searchqueryset.spelling_suggestion(self.cleaned_data['q'])


class FacetedSearchForm(SearchForm):
    def __init__(self, *args, **kwargs):
    self.selected_facets = kwargs.pop("selected_facets", [])
    super(FacetedSearchForm, self).__init__(*args, **kwargs)

    def search(self):
    sqs = super(FacetedSearchForm, self).search()

    # We need to process each facet to ensure that the field name and the
    # value are quoted correctly and separately:
    for facet in self.selected_facets:
        if ":" not in facet:
            continue

        field, value = facet.split(":", 1)

        if value:
            sqs = sqs.narrow(u'%s:"%s"' % (field, sqs.query.clean(value)))

    return sqs

如何将 CSS 类“myspecialcssclass”添加到字段“q”中，在我的应用程序“forms.py”中扩展此类？我需要扩展的类是“FacetedSearchForm”。有什么线索吗？

Answer 1

from haystack.forms import FacetedSearchForm

class CustomSearchForm(FacetedSearchForm)
    q = forms.CharField(required=False, label='Search', widget=forms.widgets.TextInput(attrs={"class":"myspecialcssclass",}))

您的自定义表单必须在您的 haystack url 中设置，例如：

from haystack.views import SearchView

urlpatterns = patterns('haystack.views',
    url(r'^
另请参阅 haystack 视图和表单文档
, SearchView(form_class=CustomSearchForm, results_per_page=20), name='haystack_search'),
)

另请参阅 haystack 视图和表单文档

Answer 2

我认为：

https://docs.djangoproject。 com/en/dev/ref/forms/widgets/#customizing-widget-instances

可能会有所帮助。

基本上，您需要子类化FacetedSearchForm 并向您的小部件添加一个参数

class MyForm(FacetedSearchForm):
    q = forms.CharField(
            required=False,
            label='Search',
            widget=forms.TextInput(attrs={'class':'myspecialcssclass'}))

，这应该就是这样。

Answer 3

表单字段小部件 attrs 将 html 属性映射到它们的值。在子类 __init__ 函数中重写这些属性以安全地修改字段。

class MyForm(FacedSearchForm):
    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.fields['q'].widget.attrs['class'] = 'myspecialcssclass'