Question

我正在尝试使用两个下拉菜单创建一个网站：部门和课程编号。下拉菜单的数据来自＆＃34;课程＆＃34;我的SQL数据库的表。现在我的网站正确初始化，并在下拉菜单中显示正确的选项。但是，当用户在下拉菜单中选择一个选项并提交他们的选择时，网站将重新加载为空白平板，以便不保存或处理他们的选择。错误位于CourseForm表单中的某处，因为我有另一种形式（Working_Form），它以不同的方式创建但完美地运行。 CourseForm /其相关模型有什么问题？

models.py

from django.db import models

class Dept(models.Model):
    dept = models.CharField(max_length=255, db_column = 'dept')
    class Meta:
        managed = False
        db_table = 'courses'
    def __str__(self):
        return self.dept

class Course_num(models.Model):
    course_num = models.CharField(max_length=255, db_column = 'course_number')
    class Meta:
        managed = False
        db_table = 'courses'
    def __str__(self):
        return self.course_num

forms.py

from django import forms
from django_select2.forms import ModelSelect2Widget
from .models import Dept, Course_num

class CourseForm(forms.Form):
    dept = forms.ModelChoiceField(
        queryset=Dept.objects.distinct().\
            order_by('dept').exclude(dept__isnull=True),
        required=False,
        empty_label="No preference",
        label=u"Department")

    course_num = forms.ModelChoiceField(
        queryset=Course_num.objects.distinct().\
            order_by('course_num').exclude(course_num__isnull=True),
        required=False,
        empty_label="No preference",
        label=u"Course Number")

views.py

from django.shortcuts import render
from django import forms
from .models import Dept, Course_num
from .forms import CourseForm 
...
class Working_Form(forms.Form):
    working_info = forms.ChoiceField(choices=WORKING_DATA_LIST, required=False)
    show_args = forms.BooleanField(label='Show args_to_ui',
                               required=False)

def home(request):
    context = {}
    res = None
    if request.method == 'POST':
        form_CourseForm = CourseForm(request.POST)
        working_info = Working_Form(request.POST)
        args = {}
        if form_CourseForm.is_valid():
            data = form_CourseForm.cleaned_data
            if data['dept']:
                args['dept'] = data['dept']
            if data['course_num']:
                args['course_num'] = data['course_num']
        if working_info.is_valid():
            ...
            if working_info.is_valid.cleaned_data['show_args']:
                context['args'] = 'args_to_ui = ' + json.dumps(args, indent=2)

        if ('dept' in args) == ('course_num' in args): 
            try:
                results = process_inputs(args)
            except Exception as e:
                print('Exception caught')
        else:
            context['err'] = forms.ValidationError("Error")
            results = None

    else:
        form_CourseForm = CourseForm()
        working_info = Working_Form()
    # handle situation when results is None (i.e. no inputs have been entered)

    if results is None:
        context['result'] = None

    else: #process output info
        context['num_results'] = len(results)

    context['form_CourseForm'] = form_CourseForm
    context['working_info'] = working_info
    return render(request, 'index.html', context)

修改将方法从GET更改为POST后，我仍面临同样的问题。我使用views.py代码来手动设置args字典，发现无论form_CourseForm.is_valid（）的结果如何，即使我在两个下拉菜单中进行选择，也没有任何内容添加到args中。这对我来说没有意义，但似乎form_CourseForm根本不起作用？

def home(request):
    context = {}
    res = None
    if request.method == 'POST':
        form_CourseForm = CourseForm(request.POST)
        form_prof_fn = SearchForm_prof_fn(request.POST)
        form_prof_ln = SearchForm_prof_ln(request.POST)
        args = {}
        if form_CourseForm.is_valid():
            data = form_CourseForm.cleaned_data
            if data['dept']:
                args['dept'] = "Math" #doesn't work
            if data['course_num']:
                args['course_num'] = "100" #doesn't work
        else:
            args['dept'] = "History" #doesn't work
        args['rv'] = "123" #does work, so issue isn't with args itself

的index.html

<html>
    <head>
        <title>Website</title>
        <link rel="stylesheet" type="text/css" href="{% static "/main.css" %}" />
    </head>
    <body>
        <div id="header">
            <h1>Website</h1>
        </div>
        <div class="frame">
            <form method="post">
                {% csrf_token %}
                <table class="form_CourseForm">
                    {{ form_CourseForm }}
                </table>                                  
                <p>and/or</p>
                <table class="Working Form">
                    {{ working_form }}
                </table>
                <input type="submit" value="Submit" />
            </form>
        </div>

        {% if args %}
        <div class="args">
            <pre>{{ args }}</pre>
        </div>
        {% endif %}

...code to print output table...
    </body>
</html>

Answer 1

    package com.example.jdev.trytry;

import android.support.v7.widget.RecyclerView;
import android.view.ContextMenu;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.List;

/**
 * Created by jdev on 3/5/2018.
 */

public class userAdapter extends RecyclerView.Adapter<userAdapter.UserViewHolder>{

    private List<userModel> list;

    public userAdapter(List<userModel>list){
        this.list = list;
    }

    @Override
    public UserViewHolder onCreateViewHolder (ViewGroup parent, int viewType){
        return new UserViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.view_item, parent, false));
    }

    @Override
    public void onBindViewHolder (final UserViewHolder holder, int position){

        userModel user = list.get(position);
        holder.textName.setText(user.name);
        holder.textCompanyName.setText(user.companyName);
        holder.textAddress.setText(user.address);
        holder.textEmail.setText(user.email);
        holder.textNumber.setText(user.number);

        holder.itemView.setOnCreateContextMenuListener(new View.OnCreateContextMenuListener() {
            @Override
            public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {

                menu.add(holder.getAdapterPosition(), 0 , 0 , "sample1");
                menu.add(holder.getAdapterPosition(), 1, 0, "sample2");
            }
        });
    }

    @Override
    public int getItemCount(){
        return list.size();
    }


    class UserViewHolder extends RecyclerView.ViewHolder {

        TextView textName, textCompanyName, textAddress, textEmail, textNumber;

        public UserViewHolder (View itemView) {

            super(itemView);

            textName = itemView.findViewById(R.id.text_name);
            textCompanyName = itemView.findViewById(R.id.text_companyName);
            textAddress = itemView.findViewById(R.id.text_address);
            textEmail = itemView.findViewById(R.id.text_email);
            textNumber = itemView.findViewById(R.id.text_number);

        }
    }
}

以及html

def home(request):
    context = {}
    res = None
    if request.method == 'POST':
        form_CourseForm = CourseForm(request.POST)
        working_info = Working_Form(request.POST)
        args = {}
        if form_CourseForm.is_valid():
            if request.POST['dept']:
                args['dept'] = request.POST['dept']
            if request.POST['course_num']:
                args['course_num'] = request.POST['course_num']
        if working_info.is_valid():
            ...

        if ('dept' in args) == ('course_num' in args): 
            try:
                results = process_inputs(args)
            except Exception as e:
                print('Exception caught')
        else:
            context['err'] = forms.ValidationError("Error")
            results = None
        return render(request,'template.html',{'args':args})
    else:
        form_CourseForm = CourseForm()
        working_info = Working_Form()

Django表示不保存输入 - 提交后刷新

1 个答案: