DateTime.now() doesn't update correctly-CodePudding

I created a small app where you can add comments to posts, and this is the code to add the comment to firestore

final DateTime timestamp = DateTime.now();

addComment() async{
   commentsRef.doc(postId).collection('comments').add({
     'username': current.uniqueName,
     'comment': commentController.text,
     'timestamp': timestamp,
     'avatarUrl': current.profilePictureURL,
     'userId': current.userID
});}

But, if I post a comment and after a couple of seconds I post another one, both the posts have the same timestamp. What can it be related to? How can I solve this problem?

CodePudding user response：

The correct usage is:

addComment() async{
   commentsRef.doc(postId).collection('comments').add({
     'username': current.uniqueName,
     'comment': commentController.text,
     'timestamp': DateTime.now(),
     'avatarUrl': current.profilePictureURL,
     'userId': current.userID
});}

You store the timestamp in the final variable, and never update it. That's why you get the same value in the database.