Django:管理员中的AJAX ManyToManyField

时间:2011-02-13 12:25:59

标签: ajax django django-admin manytomanyfield

我想在管理员中显示ManyToManyField,就像filter_horizontal一样,但是在用户输入过滤器字段时填充选项。有很多选项,一次加载它们需要花费很多时间。

我发现django-ajax-filtered-fields但在我看来它是一种矫枉过正,因为它需要更改模型类,当我想要做的就是替换表单中的每个多个选择字段时。

编写一个继承自admin.widgets.FilteredSelectMultiple的自定义窗口小部件字段似乎是正确的方法。所以我试图推出自己的小部件:

class MultiSelectWidget(FilteredSelectMultiple):
    class Media:
        # here should be some js to load options dynamically
        js = (
            "some_js_to_load_ajax_options.js",
        )

    def render_options(self, choices, selected_choices):
        # this initializes the multiple select without any options
        choices = [c for c in self.choices if str(c[0]) in selected_choices]
        self.choices = choices
        return super(MultiSelectWidget, 
                     self).render_options([], selected_choices)

class MyAdminForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(MyAdminForm, self).__init__(*args, **kwargs)
        self.fields['m2m_field'].widget = MultiSelectWidget('m2m_field', is_stacked=False)
    class Meta:
        model = MyModel

class MyAdmin(admin.ModelAdmin):
    form = MyAdminForm

正确呈现。

但我不确定如何实现这个some_js_to_load_ajax_options.js ajax部分。我应该编写自己的jQuery代码段还是修改SelectFilter2附带的admin/media/js?以前有人去过吗?

修改 虽然与问题的核心无关,但由于我只想覆盖字段的小部件,因此更短的方法是使用formfield_overrides

class MultiSelectWidget(FilteredSelectMultiple):
    # as above

class MyAdmin(admin.ModelAdmin):
    formfield_overrides = {
        models.ManyToManyField: {'widget': MultiSelectWidget},
    }

3 个答案:

答案 0 :(得分:4)

我从你的代码开始,我使用自定义javascript从photologue Photo模型中检索值;请注意我正在使用grappelli和Django url来获取json对象是硬编码的;我模型中的字段也称为“照片”:

# urls.py
url(r'^get_json_photos/(?P<query>[\w-]+)/$', 'catalogo.views.get_json_photos', name='get_json_photos'),


# views.py    
from photologue.models import Photo
from django.utils import simplejson as json

def get_json_photos(request, query):
    photos = Photo.objects.filter(title__icontains=query)[:20]
    p = [ {"name":photo.title, "id":photo.id} for photo in photos ]
    response = json.dumps(p)
    return HttpResponse(response, mimetype="application/json")


# admin.py
from django.conf import settings
from django.contrib.admin.widgets import FilteredSelectMultiple

class MyFilteredSelectMultiple(FilteredSelectMultiple):

    class Media:
        js = (settings.ADMIN_MEDIA_PREFIX + "js/core.js",
              settings.ADMIN_MEDIA_PREFIX + "js/SelectBox.js",
              settings.ADMIN_MEDIA_PREFIX + "js/SelectFilter2.js",
              settings.MEDIA_URL + "js/ajax_photo_list.js")


class MyModelMultipleChoiceField(ModelMultipleChoiceField):

    def clean(self, value):
        return [val for val in value]


class GalleryForm(forms.ModelForm):
    photos = MyModelMultipleChoiceField(queryset=Photo.objects.none(), required=False,
        widget=MyFilteredSelectMultiple(verbose_name="photos", is_stacked=False))

    def __init__(self, *args, **kwargs):
        super(GalleryForm, self).__init__(*args, **kwargs)
        try:
            i = kwargs["instance"]
            gallery = Gallery.objects.get(pk=i.pk)
            qs = gallery.photos.all()
        except:
            qs = Photo.objects.none()
        self.fields['photos'].queryset = qs

    class Meta:
        model = Gallery
        widgets = {
            'photos': MyFilteredSelectMultiple(verbose_name="photos", is_stacked=False)
        }


class GalleryAdmin(admin.ModelAdmin):
    list_display = ('title', 'date_added', 'photo_count', 'is_public')
    list_filter = ['date_added', 'is_public']
    date_hierarchy = 'date_added'
    prepopulated_fields = {'title_slug': ('title',)}
    filter_horizontal = ()
    form = GalleryForm


# ajax_photo_list.js 
(function($){
$("#id_photos_input").live("keyup", function(){
    var querystring = $("#id_photos_input").val();
    if (querystring) {
        $.ajax ({
            type: "GET",
            url: "/get_json_photos/"+querystring+"/",
            cache: false,
            success: function(json) {
                if (json) {
                    var list_from = $("#id_photos_from option").map(function() {
                        return parseInt($(this).val());
                    });
                    var list_to = $("#id_photos_to option").map(function() {
                        return parseInt($(this).val());
                    });
                    for (var pid in json) {
                        if ($.inArray(json[pid].id, list_from) == -1 && $.inArray(json[pid].id, list_to) == -1) {
                            $("#id_photos_from").prepend("<option value='"+json[pid].id+"'>"+json[pid].name+"</option>");
                        }
                    }
                    SelectBox.init('id_photos_from');
                    SelectBox.init('id_photos_to');
                }
            }
        });
    }
})
}(django.jQuery));

我正在考虑让它变得通用,因为这不是我第一次遇到这个问题,

答案 1 :(得分:0)

我会破解选择过滤器,它有一组很好的功能可以使用。

答案 2 :(得分:0)

如果Select2的用户界面吸引您,您可以在管理员中使用Django-Select2

对于m2m,它可能会像你建议的那样工作:

class MyAdmin(admin.ModelAdmin):
    formfield_overrides = {
        models.ManyToManyField: {'widget': ModelSelect2MultipleWidget},
    }

    # required to make jquery available to select2
    # has to be loaded via Admin class (and not via widget or form class) for correct order in output
    class Media:
        js = ("ext/js/jquery.min.js",)

Ajax的工作原理是将以下网址格式添加到urls.py

# if using ModelWidget
url(r'^select2/', include('django_select2.urls')),

当然,您也可以提供自己的视图实现,请参阅上面链接的文档。

我目前没有将它用于m2m,而是用于反向外键关系,因此我在Django管理员中以自定义形式使用它,明确地实例化窗口小部件。因此,如果它不与formfield_overrides合作,那么漫长的选择将是一种选择。