Flutter how to update Listview.builder if the data is changes

Question

I'm working with a ListView.builder in Flutter. For now all was working fine, I have the follwing lines of code in the callback methods:

@override
void initState(){
  items = new List();
  for(int index = 0; index < dataList.length; index++){
    items.add(...creating widget ..);
  }
}

 @override
  Widget build(BuildContext context) {
    return Container(
    child: ListView.builder(
        scrollDirection: Axis.vertical,
       shrinkWrap: true,
       itemCount: dataList.length,
       itemBuilder: (BuildContext context, int index) {
          return Container(
            width: width,
            height: 160 ,
            key: UniqueKey(),
            padding: EdgeInsets.all(10),
            child: items[index],
          );
        },
      ),
    );
  }

The problem is when the data of the dataList is updated, how should I implement this list to make the list update the UI if the data values are updated, removed or place changed. Is StreamBuilder the solution?

in your case it is dataList right? – Jitesh Mohite Sep 15 '20 at 15:51 — Jitesh Mohite, Sep 15 '20 at 15:51

Jitesh Mohite · Accepted Answer · 2020-09-15T16:16:27.817

5

If it's continuously changing then use StreamBuilder

Eg: https://bendyworks.com/blog/a-month-of-flutter-rendering-a-list-view-with-stream-builder

If not then you can use FutureBuilder

Eg: https://medium.com/nonstopio/flutter-future-builder-with-list-view-builder-d7212314e8c9

OR,

If dataList gets change inside application(remove/update), then call setState() which will update ListView

edited Sep 15 '20 at 16:16

answered Sep 15 '20 at 15:53

Jitesh Mohite

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Is continously changing but I solved this problem with a ChangeNotifier in the class definition of dataList items. The problem is when this items are removed or index changed. Which option I should use? – notarealgreal Sep 15 '20 at 15:57
how they are removing or modifying? its done inside app or on server? – Jitesh Mohite Sep 15 '20 at 15:58
Inside app, depending on user interaction. – notarealgreal Sep 15 '20 at 16:04
so whenever dataList gets modified you just have to call setState(), it will update the listview – Jitesh Mohite Sep 15 '20 at 16:06
@JiteshMohite Can u help me to solve this problem https://stackoverflow.com/questions/76331842/flutter-streambuilder-doesnt-automatically-update-listview-when-new-data-come – KJEjava48 May 25 '23 at 12:15

Flutter how to update Listview.builder if the data is changes

1 Answers1