忽略了django表单选择字段的初始值

Question

我有这样的形式:

class UserUsesSourceForm(forms.Form):
    # some fields here
    username = forms.CharField(label=("Username"), max_length=30, help_text = ("Required"))
    provider = forms.ChoiceField(widget=forms.Select(), choices=SOURCES_CHOICES, initial=SOURCES_CHOICES[1])

可用的选择是:

E = 'e'
A = 'a'
SOURCES_CHOICES = (
                  (A, 'A'),
                  (E, 'E'),
                  )

风景:

form = UserUsesSourceForm(initial={"username":request.user.username, 'provider':SOURCES_CHOICES[1]})return render_to_response('update_datasource.html', context_instance=RequestContext(request, params))

和模板:

<form action="" method="post">
    {% csrf_token %}
    {% if form.non_field_errors %}
    <p>
        {% for error in form.non_field_errors %}
            <div class="text-error">{{ error|escape }}</div>
        {% endfor %}
    </p>
    {% endif %}
    <div class="control-group">

        <label class="control-label" for="id_provider">Data source</label>
        <div class="controls">
            {{form.provider}}
        </div>
                </div>
</form>

问题是,即使初始值设置正确,我可以在调试中测试它(即表单"provider"字段初始值是我想要的元组),最终的html总是显示选择框中的第一个元素:

<select name="provider" id="id_provider">
<option value="A">A</option>
<option value="E">E</option>
</select>

..而我希望它有一个"默认"或"活动"选项.请注意,用户名字段已正确初始化.我如何进一步调查以找出问题所在？

Answer 1

您需要option在initial数据中传递值而不是元组:

form = UserUsesSourceForm(
    initial={'username':request.user.username,
             'provider':SOURCES_CHOICES[1][0]})