Using the codelab for firebase and flutter, added connectivity to the firestore database

2019-02-08 23:41:49 -06:00
commit 9d1967a9f0
60 changed files with 1594 additions and 0 deletions
--- a/flutter_app/lib/main.dart
+++ b/flutter_app/lib/main.dart
@@ -0,0 +1,93 @@
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:flutter/material.dart';
+
+void main() => runApp(MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Names',
+      home: MyHomePage(),
+    );
+  }
+}
+
+class MyHomePage extends StatefulWidget {
+  @override
+  _MyHomePageState createState() {
+    return _MyHomePageState();
+  }
+}
+
+class _MyHomePageState extends State<MyHomePage> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: Text('Baby Name Votes')),
+      body: _buildBody(context),
+    );
+  }
+
+  Widget _buildBody(BuildContext context) {
+    return StreamBuilder<QuerySnapshot>(
+      stream: Firestore.instance.collection('Lot1').snapshots(),
+      builder: (context, snapshot) {
+        if (!snapshot.hasData) return LinearProgressIndicator();
+
+        return _buildList(context, snapshot.data.documents);
+      },
+    );
+  }
+
+  Widget _buildList(BuildContext context, List<DocumentSnapshot> snapshot) {
+    return ListView(
+      padding: const EdgeInsets.only(top: 20.0),
+      children: snapshot.map((data) => _buildListItem(context, data)).toList(),
+    );
+  }
+
+  Widget _buildListItem(BuildContext context, DocumentSnapshot data) {
+    final record = Record.fromSnapshot(data);
+
+    return Padding(
+      key: ValueKey(record.name),
+      padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
+      child: Container(
+        decoration: BoxDecoration(
+          border: Border.all(color: Colors.grey),
+          borderRadius: BorderRadius.circular(5.0),
+        ),
+        child: ListTile(
+          title: Text(record.name),
+          trailing: Text(record.votes.toString()),
+          onTap: () => Firestore.instance.runTransaction((transaction) async {
+            final freshSnapshot = await transaction.get(record.reference);
+            final fresh = Record.fromSnapshot(freshSnapshot);
+
+            await transaction
+                .update(record.reference, {'votes': fresh.votes + 1});
+          }),
+        ),
+      ),
+    );
+  }
+}
+
+class Record {
+  final String name;
+  final int votes;
+  final DocumentReference reference;
+
+  Record.fromMap(Map<String, dynamic> map, {this.reference})
+      : assert(map['name'] != null),
+        assert(map['votes'] != null),
+        name = map['name'],
+        votes = map['votes'];
+
+  Record.fromSnapshot(DocumentSnapshot snapshot)
+      : this.fromMap(snapshot.data, reference: snapshot.reference);
+
+  @override
+  String toString() => "Record<$name:$votes>";
+}