day 82 Django Admin组件.

一、先建表环境

modules文件

from django.db import models

# Create your models here.
from django.contrib.auth.models import AbstractUser

class UserInfo(AbstractUser):
    '''
    用户表
    '''
    nid  =models.AutoField(primary_key=True)
    phone  =models.CharField(max_length=11,null=True,unique=True)
    avatar = models.FileField(upload_to='avatars/',default='avatars/default.png',verbose_name='头像')
    create_time =models.DateTimeField(auto_now_add=True)
    blog =models.OneToOneField(to='Blog',to_field='nid',null=True)
    def __str__(self):
        return self.username

class Blog(models.Model):
    '''
    博客信息
    '''
    nid =models.AutoField(primary_key=True)
    title =models.CharField(max_length=64)
    site =models.CharField(max_length=32,unique=True)
    theme =models.CharField(max_length=32)

    def __str__(self):
        return self.title
#

class  Category(models.Model):
    '''
    个人博客文章分类
    '''
    nid =models.AutoField(primary_key=True)
    title =models.CharField(max_length=32)#分类标题
    blog = models.ForeignKey(to ='Blog',to_field='nid')#外键关联博客，一个博客站点可以有多个分类

    def __str__(self):
        return self.title

class Tag(models.Model):
    ''''
    标签
    '''
    nid =models.AutoField(primary_key=True)
    title =models.CharField(max_length=32)
    blog =models.ForeignKey(to='Blog',to_field='nid') #所属博客

    def __str__(self):
        return self.title

class Article(models.Model):
    '''
    文章
    '''
    nid =models.AutoField(primary_key=True)
    title = models.CharField(max_length=50) #文章标题描述
    desc =models.CharField(max_length=255) #文章描述
    create_time =models.DateTimeField()#创建时间

    category = models.ForeignKey(to ='Category',to_field='nid',null=True)
    user = models.ForeignKey(to='UserInfo',to_field='nid')
    tags =models.ManyToManyField( # 中介模型
        to ='Tag',
        through='Article2Tag',
        through_fields=('article','tag')#注意顺序

    )

    def __str__(self):
        return self.title

class ArticleDetail(models.Model):
    '''
    文章详情
    '''
    nid =models.AutoField(primary_key=True)
    content = models.TextField()
    article =models.OneToOneField(to ='Article',to_field='nid')

class Article2Tag(models.Model):
    '''
    文章和标签的多对多关系表
    '''
    nid =models.AutoField(primary_key=True)
    article =models.ForeignKey(to='Article',to_field='nid')
    tag =models.ForeignKey(to ='Tag',to_field='nid')

    class Meta:
        unique_together = (('article','tag'),)

class ArticleUpDown(models.Model):
    '''
    点赞
    '''
    nid= models.AutoField(primary_key=True)
    user =models.ForeignKey(to ='UserInfo',null=True)
    article = models.BooleanField(default=True)

    class  Meta:
        unique_together = (('article','user'),)

class Comment(models.Model):
    '''
    评论表
    '''
    nid = models.AutoField(primary_key=True)
    article =models.ForeignKey(to ='Article',to_field='nid')
    user =models.ForeignKey(to ='UserInfo',to_field='nid')
    content =models.CharField(max_length=255)#评论内容
    create_time =models.DateTimeField(auto_now_add=True)
    parent_comment =models.ForeignKey('self',null=True)

    def __str__(self):
        return self.content

　

# 告诉Django项目用哪张表做认证

AUTH_USER_MODEL ='app01.UserInfo'

新建一个管理员账号 

admin / dadmin01 

 通过web去登录 

修改显示的内容

 

展示的内容

设置某个字段为连接字段

 增加方法字段：

 

批量初始化 

重写页面

 

 

 

Admin的实现流程

1. 启动

　　 import admin 

　　def autodiscover():

　　　　autodiscover_modules('admin', register_to=site)

　　执行每个app下的admin.py文件

　　

 

2. 注册 （单例模式 singlelton pattern）

3. 

 

 

单例模式 

 

# class Person(object):
#
#     def __init__(self,name,age):
#         self.name=name
#         self.age=age
#
#
# alex=Person("alex",33)
# egon=Person("egon",32)

　　

# 单例模式方式1 ：__new__

# class Singleton(object):
#
#     _instance = None
#     def __new__(cls, *args, **kw):
#         if not cls._instance:
#             cls._instance = super(Singleton, cls).__new__(cls, *args, **kw)
#         return cls._instance
#
# class MyClass(Singleton):
#     a = 1
#
#
#
# mc1=MyClass()
#
# mc2=MyClass()
#
# mc3=MyClass()


# print(id(mc1))
# print(id(mc2))
# print(id(mc3))

　　

# 单例模式方式2 ：模块方式

 

# 思考1
# from mysingleton import my_singleton as my_singleton_new
#
# print(id(my_singleton_new)) 
# print(id(my_singleton))

# 思考2
# import func
#
# func.bar()

# 思考3

from mysingleton import my_singleton,My_Singleton

ms1=My_Singleton()

from mysingleton import my_singleton,My_Singleton

ms2=My_Singleton()

print(id(ms1))
print(id(ms2))