如何从不同的 dart 文件访问变量？

Question

I have stored my document ID inside a string doc_id . I want to use this doc_id to access the subcollection from another file. This is how I stored the doc_id:

 onPressed: () async {
                   await FirebaseFirestore.instance
                            .collection('blogs')
                            .add({
                          'postbody': postController.text,
                       
                          
                        }).then((value) {
                          doc_id = value.id;
                          
                        }).catchError((error) => errorAlert(context));
           }

I have tried another way, like storing this doc_id as a field value inside the collection 'blog',

 await FirebaseFirestore.instance
                           .collection('blogs')
                          .doc(docid)
                          .update({'postid': docid});

But then while fetching the data using get() it needed the documentid for fetching. Is there any way that I can read values without documentid. Or how can I access this doc_id from another dart file?

Answer 1

You can read on collection to get all blog, Or run query with it to prevent read too much document one time that can increased costs, like FirebaseFirestore.instance.collection('blogs').limit(10).snapshots()