Flutter Streambuilder is duplicating items

Question

I have a StreamBuilder connected to a List and the List gets its data from Firebase, but every there is an Event in my Database the items in my Streambuilder get Duplicated.

Here is my StreamBuilder code:

StreamBuilder(
                  stream: masterListStart().asStream(),
                  builder: (context, snapshot) {
                    //return coursesList.length == 0
                    return finishedLoadingList
                        ? ListView.builder(
                            scrollDirection: Axis.horizontal,
                            shrinkWrap: true,
                            itemCount: storysList.length,
                            itemBuilder: (context, index) {
                              //
                              StoryItems data = storysList[index];
                              //
                              return StoryItems(
                                data: data,
                              );
                            },
                          )
                        : CircularProgressIndicator();
                  },
                ),

How I can prevent the StreamBuilder from doing this?

Answer 1

Instead of using finishedLoadingList, you can simply check your snapshot connectionState as following

StreamBuilder(
  stream: masterListStart().asStream(),
  builder: (context, snapshot) {
    //return coursesList.length == 0
    return (ConnectionState.done == snapshot.connectionState) ? ListView.builder(
      scrollDirection: Axis.horizontal,
      shrinkWrap: true,
      itemCount: storysList.length,
      itemBuilder: (context, index) {
        //
        StoryItems data = storysList[index];
        //
        return StoryItems(
          data: data,
        );
      },
    ) : CircularProgressIndicator();
  },
),