django中的表單佔位符顯示不正確

Question

就像標題中所述，表單窗口小部件中的佔位符屬性無法正確顯示。它是隨機的，有時它可以正常工作，有時我需要刷新瀏覽器才能顯示。 我需要它們，因爲我沒有在模板中顯示字段標籤。 反正這裏是代碼：

#FORMS.PY 
class RegistrationForm(UserCreationForm): 
    first_name = forms.CharField(label=_('First name'), max_length=30) 
    last_name = forms.CharField(label=_('Last name'), max_length=30) 
    email = forms.EmailField(label=_("Email"), required=True) 

    class Meta: 
     model = User 
     fields = ('username', 'first_name', 'last_name', 'email', 'password1', 'password2') 

    def __init__(self, *args, **kwargs): 
     super(RegistrationForm, self).__init__(*args, **kwargs) 
     # Set field Label as Placeholder for every field 
     for field in self.base_fields.values(): 
      field.widget.attrs["placeholder"] = field.label 
     # Set HTML and CSS attributes to the fields 
     self.fields['username'].widget.attrs.update({'class':TEXTINPUT_CSS}) 
     self.fields['email'].widget.attrs.update({'class':EMAILINPUT_CSS}) 
     self.fields['password1'].widget.attrs.update({'class':PASSWORDINPUT_CSS}) 
     ... 

通過我使用Django開發服務器的方式，可能來自一個事實，即服務器速度慢的問題。 任何幫助，將不勝感激

編輯：Views.py和模板的要求

#views.py 
def register(request): 
    if request.method == 'POST': 
     form = RegistrationForm(request.POST) 
     if form.is_valid(): 
      form.save() 
      if REGISTER_EMAIL_CONFIRMATION == True: 
       # Add email confirmation 
       username = form.cleaned_data['username'] 
       email = form.cleaned_data['email'] 
       salt = hashlib.sha1(str(random.random()).encode('utf-8')).hexdigest()[:5]    
       activation_key = hashlib.sha1((salt+email).encode('utf-8')).hexdigest()    
       key_expires = datetime.datetime.today() + datetime.timedelta(CONFIRMATION_KEY_EXPIRE_DAYS) 
       # Create and save User Profile 
       user=User.objects.get(username=username)    
       new_profile = UserProfile(user=user, activation_key=activation_key, key_expires=key_expires) 
      new_profile.save() 
       # Send email with activation key 
       subject_file = 'app_authentication/email_signup_confirm_subject.txt' 
       body_file = 'app_authentication/email_signup_confirm_body.html' 
       context = {'username':username, 'activation_key':activation_key} 
       send_email_from_files([email], subject_file, body_file, context) 
       return redirect('confirm_email_sent') 
      else: 
       return redirect('register_success') 
    else: 
     form = RegistrationForm() 
    return render(request, 'registration/register.html', {'form': form, 'title': _('Register')}) 


#register.html 
{% block content2 %} 
<form id="register_form" autocomplete="off" method="post" action="{% url 'register' %}"> 
{% csrf_token %} 
    <div class="clearfix"> 
    {% for field in form %} 
     <div class="form-group"> 
      {{ field }} 
      {% if form.errors %} 
      {% for error in field.errors %} 
       <div class="alert alert-error"> 
        <strong>{{ error|escape }}</strong> 
       </div> 
      {% endfor %} 
      {% endif %} 
     </div> 
    {% endfor %} 
     {% if form.errors %} 
     {% for error in form.non_field_errors %} 
      <div class="alert alert-error"> 
       <strong>{{ error|escape }}</strong> 
      </div> 
     {% endfor %} 
     {% endif %} 
    </div> 
    <!-- Send Button --> 
    <div class="pt-10"> 
     <button class="submit_btn btn btn-mod btn-medium btn-round btn-full" id="reg-btn" name="submit">{{ title }}</button> 
    </div> 
</form> 
{% endblock content2 %} 

截圖：

當我啓動開發服務器，並嘗試登錄：

我刷新瀏覽器後的相同登錄頁面：

@akarilimano：

class LoginForm(AuthenticationForm): 
    # username doesn't have label in AuthenticationForm 
    username = forms.CharField(label=_("Username"), max_length=254) 

    def __init__(self, *args, **kwargs): 
     super(LoginForm, self).__init__(*args, **kwargs) 
     # Set field Label as Placeholder for every field 
     for field in self.base_fields.values(): 
      print(field.label) 
      field.widget.attrs['placeholder'] = field.label 

Answer 1

嘗試改變這裏base_fields：

for field in self.base_fields.values(): 

到fields：

for field in self.fields.values(): 

---

base_fields字典是一組基本的類定義的字段。你可以改變它，但不建議，在你的情況下不需要。

我想如果你改變base_fields後打電話super您的版本將工作：

def __init__(self, *args, **kwargs): 
    for field in self.base_fields.values(): 
     field.widget.attrs["placeholder"] = field.label 
    super(RegistrationForm, self).__init__(*args, **kwargs) 

Answer 2

爲什麼你需要這個代碼，如果你已經在Meta定義model = User？

first_name = forms.CharField(label=_('First name'), max_length=30) 
last_name = forms.CharField(label=_('Last name'), max_length=30) 
email = forms.EmailField(label=_("Email"), required=True) 

也許他們與模型字段發生衝突？你可以嘗試刪除非模型表單域？

Answer 3

嘗試定義你的佔位符直接作爲控件屬性，如：

class RegistrationForm(UserCreationForm): 
     first_name = forms.CharField(label=_('First name'), max_length=30, widget=forms.TextInput(attrs={"placeholder": "First name"})) 
     last_name = forms.CharField(label=_('Last name'),max_length=30, widget=forms.TextInput(attrs={"placeholder": "Last Name"})) 
     email = forms.EmailField(label=_("Email"), required=True, widget=forms.TextInput(attrs={"placeholder": "Email"}))