# Application definition    INSTALLED_APPS = [      'django.contrib.admin',      'django.contrib.auth',      'django.contrib.contenttypes',      'django.contrib.sessions',      'django.contrib.messages',      'django.contrib.staticfiles',      'Xadmin.apps.XadminConfig',      'blogs.apps.BlogsConfig',      'bigs.apps.BigsConfig',  ]

from django.contrib.admin.sites import AdminSite, site  from django.utils.module_loading import autodiscover_modules    def autodiscover():      autodiscover_modules('admin', register_to=site)

class AdminSite(object):      """      An AdminSite object encapsulates an instance of the Django admin application, ready      to be hooked in to your URLconf. Models are registered with the AdminSite using the      register() method, and the get_urls() method can then be used to access Django view      functions that present a full admin interface for the collection of registered      models.      """          def __init__(self, name='admin'):          self._registry = {}  # model_class class -> admin_class instance          self.name = name          # 关于register的方法        def register(self, model_or_iterable, admin_class=None, **options):            if not admin_class:              admin_class = ModelAdmin            # Instantiate the admin class to save in the registry          self._registry[model] = admin_class(model, self)      #备注：截取的源码中的一部分          

class ModelAdmin(BaseModelAdmin):      "Encapsulates all admin options and functionality for a given model."        list_display = ('__str__',)      list_display_links = ()      list_filter = ()      list_select_related = False      list_per_page = 100      list_max_show_all = 200      list_editable = ()      search_fields = ()      date_hierarchy = None      save_as = False      save_as_continue = True      save_on_top = False      paginator = Paginator      preserve_filters = True      inlines = []        # Custom templates (designed to be over-ridden in subclasses)      add_form_template = None      change_form_template = None      change_list_template = None      delete_confirmation_template = None      delete_selected_confirmation_template = None      object_history_template = None      popup_response_template = None        # Actions      actions = []      action_form = helpers.ActionForm      actions_on_top = True      actions_on_bottom = False      actions_selection_counter = True      checks_class = ModelAdminChecks        def __init__(self, model, admin_site):          self.model = model          self.opts = model._meta          self.admin_site = admin_site          super(ModelAdmin, self).__init__()        def __str__(self):          return "%s.%s" % (self.model._meta.app_label, self.__class__.__name__)

# 使用model代指模型类的类名  model._meta.model_name   #得到字符串格式的类名（全小写的）    model._meta.app_label   #可以得到当前类所在APP的字符串的名字

# 补充
model._meta.get_field("字符串格式的字段属性")   # 得到一个字段属性的对象field_obj，这样我们就可以利用这个字段对象取得属性
　　　　　　　　　　　　　　　　　　　　　　　　　　　　#  比如：  field_obj.verbose_name     

from django.conf.urls import url    from django.contrib import admin    def get_urls_operate():      emp = []      emp.append(url(r'^$',查询页面的视图函数))      emp.append(url(r'^add/$',添加页面的视图函数))      emp.append(url(r'^(d+)/change/$',编辑页面的视图函数))      emp.append(url(r'^(d+)/delete/$',删除页面的视图函数))      return emp      def get_urls():      temp = []      for model,main_class_obj in admin.site._registry.items():          app_name = model._meta.app_label          model_name = model._meta.model_name          temp.append(url(r'^{}/{}/'.format(app_name,model_name),(get_urls_operate(),None,None)))   #实现第二层路由的分发      return temp    urlpatterns = [       url(r'^Xadmin/',(get_urls(),None,None))     #自定义一个前缀  实现第一层路由的分发  ]

from django.apps import AppConfig      class BlogsConfig(AppConfig):      name = 'blogs'

MODELS_MODULE_NAME = 'models'      class AppConfig(object):      """      Class representing a Django application and its configuration.      """        def __init__(self, app_name, app_module):          # Full Python path to the application eg. 'django.contrib.admin'.          self.name = app_name        def ready(self):          """          Override this method in subclasses to run code when Django starts.
　　　　#这句话的语义为：在子类中重写此方法，以便在Django启动时运行代码          """

from django.apps import AppConfig  from django.utils.module_loading import autodiscover_modules      class XadminConfig(AppConfig):      name = 'Xadmin'      def ready(self):          autodiscover_modules('Xadmin')   #Django启动时会自动扫描每个app下的Xadmin.py文件

from blogs import models  from Xadmin.service.Xadmin import site    site.register(models.UserInfo)  site.register(models.Book)

from django.conf.urls import url  from django.shortcuts import HttpResponse,render    class ModelXadmin(object):      def __init__(self,model,site):          self.model = model          self.site = site        def show(self,request):          data_list = self.model.objects.all()          return render(request,'show.html',locals())  #locals()  请函数内部所有的键值对存储 == {"data_list":data_list}        def add(self,request):          return HttpResponse('添加页面')        def edit(self,request, pk):          return HttpResponse('编辑页面')        def delete(self,request, pk):          return HttpResponse('删除页面')        @property      def get_urls_operate(self):          emp = []          emp.append(url(r'^$', self.show))          emp.append(url(r'^add/$', self.add))          emp.append(url(r'^(d+)/change/$', self.edit))          emp.append(url(r'^(d+)/delete/$', self.delete))          return emp        @property      def urls(self):          return self.get_urls_operate,None,None      class XadminSite(object):      def __init__(self,name='xadmin'):          self._registry = {}        def register(self,model,class_main=None,**option):          if not class_main:              class_main = ModelXadmin          self._registry[model] = class_main(model,self)        @property      def get_urls(self):          # print(admin.site._registry)          temp = []          for model, model_admin_object in self._registry.items():              model_name = model._meta.model_name              model_app = model._meta.app_label              temp.append(url(r'^{}/{}/'.format(model_app, model_name), model_admin_object.urls))          return temp        @property      def urls(self):          return self.get_urls,None,None      site = XadminSite()