Ndtyjky

I followed the startup name generator tutorial in the flutter website and there was no problem.
But then I wanted to add the ability to remove wordpairs from the saved list. That worked too but when a word was removed from the list, the listview wouldn't update and I had to go back to the main page and open the list again to see the effect. I searched for a way to update the listview at the setState function that I delete the wordpair in, but I could't find anything. So after removing the wordpair in the setstate, I just popped the route and pushed it again.
Can anyone suggest a better way?
Thanks

You might be able to do that using a StreamBuilder. Using that, your argument should like the following:

stream: FirebaseDatabase.instance.reference().child(

      "profiles").onValue

As you can see, the onValue will automatically update your screen whenever you delete a value.

Assuming you've just used the main.dart from the startup name generator tutorial, then you can just modify your _buildRow function to add a delete button which will then call setState and modify the _suggestions list like this:

Widget _buildRow(WordPair pair) {

    return ListTile(

        title: Text(

          pair.asPascalCase,

          style: _biggerFont,

        ),

        subtitle: RaisedButton(

            child: Text('delete'),

            onPressed: () {

              setState(() {

                _suggestions.remove(pair);

              });

            }));

  }

And here's the full main.dart:

import 'package:flutter/material.dart';

import 'package:english_words/english_words.dart';



void main() => runApp(MyApp());



class MyApp extends StatelessWidget {

  @override

  Widget build(BuildContext context) {

    return MaterialApp(

      title: 'Startup Name Generator',

      home: RandomWords(),

    );

  }

}



class RandomWordsState extends State<RandomWords> {

  final _suggestions = <WordPair>;



  final _biggerFont = const TextStyle(fontSize: 18.0);



  Widget _buildSuggestions() {

    return ListView.builder(

        padding: const EdgeInsets.all(16.0),

        itemBuilder: (context, i) {

          // Add a one-pixel-high divider widget before each row in theListView.

          if (i.isOdd) return Divider();



          final index = i ~/ 2;

          if (index >= _suggestions.length) {

            _suggestions.addAll(generateWordPairs().take(10));

          }

          return _buildRow(_suggestions[index]);

        });

  }



  Widget _buildRow(WordPair pair) {

    return ListTile(

        title: Text(

          pair.asPascalCase,

          style: _biggerFont,

        ),

        subtitle: RaisedButton(

            child: Text('delete'),

            onPressed: () {

              setState(() {

                _suggestions.remove(pair);

              });

            }));

  }



  @override

  Widget build(BuildContext context) {

    return Scaffold(

      appBar: AppBar(

        title: Text('Startup Name Generator'),

      ),

      body: _buildSuggestions(),

    );

  }

}



class RandomWords extends StatefulWidget {

  @override

  RandomWordsState createState() => new RandomWordsState();

}

I fixed it by making the list of saved pairs a separate stateful widget. I knew this would make the list refresh each time I deleted a pair but I thought the link between the states of the two stateful widgets would be lost and any time I deleted a pair from the list of saved pairs, the favorite icon in the other stateful widget would not update. But amazingly I was wrong. The states are somehow connected. I assume its because they're two stateful widgets on the same stack. I'm beginning to really like flutter.