In case when you need to initialize form with already predefined details of the form instance, for example form that add comment to a post - you can predefine post_id in the form instance instead applying it in the save() method.
Easy way to redirect user on previous (original) page after form processing it is use HTTP_REFERER header, here an example how it’s may be implemented in the get_success_url() of the Django’s class based view.
In case if you need to make some validation steps directly in the view’s def form_valid() method and raise an ValidationError here an example
Working with complex views that process multiple forms you can stuck on situation when some of forms didn’t valitated but you have not see a reason for this, to debug this you can print forms errors from the view POST method.
Sometimes you need to represent boolean field of the Django model as dropdown list choices, like “Yes/No” instead default boolean field form widget - CheckboxInput. You can implement it like this.
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