Django在ModelForm中添加ManyToManyField

Question

Sorry that this is like the thousandth question for this issue but I still can't see a light at the end of the tunnel.

Lets say I have two models:

class Video(models.Model):
title = models.CharField(u"Titel",max_length=200)
slug = AutoSlugField(populate_from='title',unique=True)
date = models.DateField("Datum")
description = models.TextField(u"Beschreibung")
user = models.OneToOneField(User, blank=True, null=True)

class Channel(models.Model):
name = models.CharField(u"Name",max_length=30)
slug = AutoSlugField(populate_from='name',unique=True)
videos = models.ManyToManyField('videoportal.Video',related_name="contained_videos",blank=True,null=True)
created = models.DateTimeField(auto_now_add=True)
modified = models.DateTimeField(auto_now=True)

As you see I want to have a channel with video(s) in it. So if I ad a video using a ModelForm like this

class VideoForm(ModelForm):
    class Meta:
        model = Video

the form I get will not contain a input field to select a channel (of course not). So how can I do this? How can I have a input field in my form to select one channel with a drop down?

Thanks, Philip

Answer 1

If a video only belongs in one channel just give your Video model a ForeignKey to your Channel model. If it should belong to more than one channel I'd use a ManyToManyField in the Video model, as already suggested.

I think this would fit the idea of uploading videos and adding it to a channel far better than doing it the other way around.

Answer 2

Use a custom form instead of Django ModelForm.

probably something like this,

class VideoForm(forms.Form):
    title = forms.CharField()
    description = forms.TextField()
    channel = forms.ModelChoiceField(queryset= Channel.objects.all(), empty_label=None)

do your validation in a view. Use Model save() method to save information contained in your POSTed form.

Answer 3

Try putting the ManyToMany field in the Video model and omit it from the Channel model:

class Video(model.Model):
    ...
    channels = model.ManyToManyField('videoportal.Channel', related_name='videos')
    ...

If you want a simple dropdown to select a single channel, why is it a many-to-many realationship between videos and channels?