首页列表显示全部问答，完成问答详情页布局。

1. 首页列表显示全部问答：
   1. 将数据库查询结果传递到前端页面 Question.query.all()
   2. 前端页面循环显示整个列表。
   3. 问答排序
2. 完成问答详情页布局：
   1. 包含问答的全部信息
   2. 评论区
   3. 以往评论列表显示区。
3. 在首页点击问答标题，链接到相应详情页。

from flask import Flask,render_template,request,redirect,url_for,session
from flask_sqlalchemy import SQLAlchemy
import config
from functools import wraps
from datetime import datetime
app = Flask(__name__)
app.config.from_object(config)
db=SQLAlchemy(app)

class User(db.Model):
    __table__name = 'user'
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    username = db.Column(db.String(20),nullable=False)
    password = db.Column(db.String(20),nullable=False)
    nickname = db.Column(db.String(50))

class Question(db.Model):
    __tablename__ = 'question'
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    title=db.Column(db.String(100),nullable=False)
    detail=db.Column(db.Text,nullable=False)
    creat_time = db.Column(db.DateTime,default=datetime.now)
    author_id=db.Column(db.Integer,db.ForeignKey('user.id'))
    author=db.relationship('User',backref=db.backref('question'))
db.create_all()


@app.route('/')
def index():
    context = {
        'question': Question.query.all()
    }
    # question : Question.query.all()
    return render_template('index.html', **context)

@app.route('/regist/',methods=['GET','POST'])
def regist():
    if request.method=='GET':
        return render_template('regist.html')
    else:
        username=request.form.get('username')
        password=request.form.get('password')
        nickname=request.form.get('nickname')
        user=User.query.filter(User.username==username).first()
        if user:
            return u'username existed'
        else:
            user=User (username=username,password=password,nickname=nickname)
            db.session.add(user)
            db.session.commit()
            return redirect(url_for('login'))


@app.route('/login/',methods=['GET','POST'])
def login():
    if request.method=='GET':
        return render_template('login.html')
    else:
        username=request.form.get('username')
        password=request.form.get('password')
        user = User.query.filter(User.username == username).first()
        if user:
            if user.password==password:
                session['user']=username
                return redirect(url_for('index'))
            else:
                return u'password error'
        else:
            return u'username is not existed'



@app.context_processor
def mycontext():
    usern=session.get('user')
    if usern:
        return{'username':usern}
    else:
        return{}

@app.route('/logout/')
def logout():
    session.clear()
    return redirect(url_for('index'))


def loginFirst(func):
    @wraps(func)
    def wrapper(*args,**kwargs):
        if session.get('user'):
            return func(*args,**kwargs)
        else:
            return redirect(url_for('login'))
    return  wrapper


@app.route('/lable/',methods=['GET','POST'])
@loginFirst
def lable():
    if request.method == 'GET':
        return render_template('lable.html')
    else:
        title = request.form.get('title')
        detail = request.form.get('detail')
        author_id = User.query.filter(User.username == session.get('user')).first().id
        question = Question(title=title, detail=detail, author_id=author_id)
        db.session.add(question)
        db.session.commit()
    return redirect(url_for('index'))

@app.route('/detail/')
def detail():
    return render_template('detail.html')

if __name__ == '__main__':
    app.run(debug=True)

detail.html

{% extends 'base.html' %}

{% block title %}Detail{% endblock %}

{% block head %}
{#    <link href="{{ url_for('static',filename='.../static/css/detail.css') }}" rel="stylesheet" type="text/css">#}
{% endblock %}

{% block main %}
<div class="detail">
    <h2>title</h2>
    <a href="#">username</a>
    <span>creat_time</span>
    <div class="p">
        <p>detail</p>
    </div>
    <textarea rows="5"></textarea><br>
    <button >发送</button>
    <br>
    <ul>
        <p>Comment</p>
        <li>
            <a href="#">username</a>
            <span>creat_time</span><br>
            <p>comment</p>
        </li>
        <li>
            <a href="#">username</a>
            <span>creat_time</span><br>
            <p>comment</p>
        </li>
    </ul>
</div>
{% endblock %}

index.html

{% extends 'base.html' %}

{% block title %}首页{% endblock %}

{% block head %}
    <link href="{{ url_for('static',filename='css/index.css') }}" rel="stylesheet" type="text/css">
    <script src="{{ url_for('static',filename='js/index.js') }}"></script>
{% endblock %}

{% block main %}
    <ul class="list-group">
    <li class="list-group-item">
        <span class="glyphicon glyphicon-leaf" aria-hidden="true"></span>
        <a href="#">username</a>
        <br>
        <a href="#"title></a>
        <span class="badge">create_time</span>
       <p>{{ question }}</p>
        {% for b in question %}
                <li class="list-group-item" >
                    <a href="#">{{ b.author.username }}</a> <span class="badge">{{ b.creat_time }}</span>
                    <p class="abstract">{{ b.detail }}</p>
                </li>
        {% endfor %}
</ul>
<div>
    <div class="img">
        <a href="http://www.baidu.cn/">
         <img src="http://p3.so.qhimgs1.com/bdr/_240_/t015a62ea10ce841183.jpg"></a>
        <div align="center"><a href="http://www.baidu.cn/" >阿斯顿马丁</a></div>
    </div>
      <div class="img">
        <a href="http://www.baidu.cn/">
         <img src="http://p2.so.qhimgs1.com/bdr/_240_/t014017698c50318c42.jpg"></a>
        <div align="center"><a href="http://www.baidu.cn/">雪佛兰</a></div>
    </div>
       <div class="img">
        <a href="http://www.baidu.cn/">
         <img src="http://p5.so.qhimgs1.com/bdr/_240_/t01d01aca9f5db2159b.jpg"></a>
        <div align="center"><a href="http://www.baidu.cn/">兰博基尼</a></div>
    </div>
        <div class="img">
        <a href="http://www.baidu.cn/">
         <img src="http://p5.so.qhimgs1.com/bdr/_240_/t01fb87f1928a69d5eb.jpg"></a>
        <div align="center"><a href="http://www.baidu.cn/">奔驰</a></div>
    </div>
</div>

{% endblock %}