Is FieldPath supported in Flutter?

问题:

I could not find FieldPath in the cloud_firestore Flutter plugin, however, I would assume that this is a very common tool that would be one of the first implementations for such a plugin.

FieldValue was recently added, but I could not find anything on FieldPath.
If I wanted to use the documentId in a query currently, would there be a way to achieve this?

回答1:

I actually forgot about this, but I added FieldPath.documentId as part of a pull request to cloud_firestore at some point.

This means that you can simply use it like this:

Firestore.instance.collection('movies').orderBy('rating').orderBy(FieldPath.documentId);

Obsolent

__name__ works if you want to target the document id.

You can use '__name__' as a String, which is equivalent to FieldPath.documentId().

String fieldPathDocumentId = '__name__';

Firestore.instance.collection('movies').orderBy('rating').orderBy(fieldPathDocumentId);