Customize/remove Django select box blank option

Haven't tested this, but based on reading Django's code here and here I believe it should work:

class ThingForm(models.ModelForm):  class Meta:    model = Thing  def __init__(self, *args, **kwargs):    super(ThingForm, self).__init__(*args, **kwargs)    self.fields['verb'].empty_label = None

EDIT: This is documented, though you wouldn't necessarily know to look for ModelChoiceField if you're working with an auto-generated ModelForm.

EDIT: As jlpp notes in his answer, this isn't complete - you have to re-assign the choices to the widgets after changing the empty_label attribute. Since that's a bit hacky, the other option that might be easier to understand is just overriding the entire ModelChoiceField:

class ThingForm(models.ModelForm):  verb = ModelChoiceField(Verb.objects.all(), empty_label=None)  class Meta:    model = Thing

from the docs

The blank choice will not be included if the model field has blank=False and an explicit default value (the default value will be initially selected instead).

so set the default and you're ok

With Carl's answer as a guide and after rooting around the Django source for a couple hours I think this is the complete solution:

1. To remove the empty option (extending Carl's example):

   class ThingForm(models.ModelForm):  class Meta:    model = Thing  def __init__(self, *args, **kwargs):    super(ThingForm, self).__init__(*args, **kwargs)    self.fields['verb'].empty_label = None    # following line needed to refresh widget copy of choice list    self.fields['verb'].widget.choices =      self.fields['verb'].choices

2. To customize the empty option label is essentially the same:

   class ThingForm(models.ModelForm):  class Meta:    model = Thing  def __init__(self, *args, **kwargs):    super(ThingForm, self).__init__(*args, **kwargs)    self.fields['verb'].empty_label = "Select a Verb"    # following line needed to refresh widget copy of choice list    self.fields['verb'].widget.choices =      self.fields['verb'].choices

I think this approach applies to all scenarios where ModelChoiceFields are rendered as HTML but I'm not positive. I found that when these fields are initialized, their choices are passed to the Select widget (see django.forms.fields.ChoiceField._set_choices). Setting the empty_label after initialization does not refresh the Select widget's list of choices. I'm not familiar enough with Django to know if this should be considered a bug.