dart - Flutter: Firebase basic Query or Basic Search code

Question

The main concept is showing document sor fields which contains the searched alphabet.

The search bar gets the given input, it send to the _firebasesearch(), but in return nothing comes out,and the above image is my database structure, trying to figure out more than a week.

CODE

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter_search_bar/flutter_search_bar.dart';

SearchBar searchBar;
GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();

class DisplayCourse extends StatefulWidget {
  @override
  _DisplayCourseState createState() => new _DisplayCourseState();
}

AppBar _buildAppBar(BuildContext context) {
  return new AppBar(
    title: new Text("FIREBASE QUERY"),
    centerTitle: true,
    actions: <Widget>[
      searchBar.getSearchAction(context),
    ],
  );
}

class _DisplayCourseState extends State<DisplayCourse> {
  String _queryText;

  _DisplayCourseState() {
    searchBar = new SearchBar(
      onSubmitted: onSubmitted,
      inBar: true,
      buildDefaultAppBar: _buildAppBar,
      setState: setState,
    );
  }

  void onSubmitted(String value) {
    setState(() {
      _queryText = value;
      _scaffoldKey.currentState.showSnackBar(new SnackBar(
        content: new Text('You have Searched something!'),
        backgroundColor: Colors.yellow,
      ));
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      key: _scaffoldKey,
      appBar: searchBar.build(context),
      backgroundColor: Colors.red,
      body: _fireSearch(_queryText),
    );
  }
}

Widget _fireSearch(String queryText) {
  return new StreamBuilder(
    stream: Firestore.instance
    .collection('courses')
    .where('title', isEqualTo: queryText)
    .snapshots(),
    builder: (context, snapshot) {
      if (!snapshot.hasData) return new Text('Loading...');
      return new ListView.builder(
        itemCount: snapshot.data.documents.length,
        itemBuilder: (context, index) =>
            _buildListItem(snapshot.data.documents[index]),
      );
    },
  );
}

Widget _buildListItem(DocumentSnapshot document) {
  return new ListTile(
    title: document['title'],
    subtitle: document['subtitle'],
  );
}

the main concept is showing document sor fields which contains the searched alphabet

the search bar gets the given input,it send to the _firebasesearch(),but in retrun nothing comes out,and the above image is my databse structure,trying to figureout more than a week,

Answer 1

Waitting for answers