Django表单提交预览按钮不起作用

Question

当我编辑配置文件并保存时，提交按钮不起作用，并且表单也没有保存。 我的views.py

class EditProfile(LoginRequiredMixin, UserPassesTestMixin, SuccessMessageMixin, PreviewMixin, generic.UpdateView):
    model = models.ParentProfile
    form_class = forms.ParentProfileForm
    template_name = "profiles/edit_profile.html"
    preview_template_name = "profiles/edit_profile_preview.html"
    success_url = reverse_lazy('profiles:show_self')

    def form_valid(self, form):
        reactivation_required = False
        for field in type(self.object).reactivation_required_fields():
            if self.object.has_changed(field):
                reactivation_required = True
                break
        if not reactivation_required or self.security_hash(form) == self.request.POST.get('hash', '0'):
            return self.done(form)
        self.process_preview(form)
        self.stage = 2
        # self.request.POST['hash'] = self.security_hash(form)
        print(self.request.POST['hash'], 'agus', self.security_hash(form))
        form = self.get_form(self.get_form_class())
        return self.render_to_response(self.get_context_data(form=form))

    def test_func(self, user):
        return user.is_parent()

    def get_object(self, queryset=None):
        return self.request.user.get_profile()

并在我的edit_profile_preview.html

中

<form action="" method="post">{% csrf_token %}
          {% for field in form %}{{ field.as_hidden }}
          {% endfor %}
          <input type="submit" class="btn btn--default" value="{% trans "Yes, I understand" %}" />
          <a class="btn btn--secondary" href="{% url 'profiles:show_self' %}">{% trans 'Cancel' %}</a>
        </form>
        {% block form_message %}
        {% endblock %}

并且此模板中的“提交”按钮不起作用。