basic file management for transactions

loc_chain_app/lib/pages/history.dart

@@ -0,0 +1,52 @@
+import 'package:flutter/material.dart';
+
+class HomePage extends StatefulWidget {
+  HomePage({Key? key, required this.title}) : super(key: key);
+  final String title;
+
+  @override
+  _HomePageState createState() => _HomePageState();
+}
+
+class _HomePageState extends State<HomePage> {
+  int _counter = 0;
+
+  void _incrementCounter() {
+    setState(() {
+      // This call to setState tells the Flutter framework that something has
+      // changed in this State, which causes it to rerun the build method below
+      // so that the display can reflect the updated values. If we changed
+      // _counter without calling setState(), then the build method would not be
+      // called again, and so nothing would appear to happen.
+      _counter++;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(widget.title),
+      ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            Text(
+              'You have pushed the button this many times:',
+            ),
+            Text(
+              '$_counter',
+              style: Theme.of(context).textTheme.headline4,
+            ),
+          ],
+        ),
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: _incrementCounter,
+        tooltip: 'Increment',
+        child: Icon(Icons.add),
+      ),
+    );
+  }
+}

loc_chain_app/lib/util/transaction.dart

@@ -1,5 +0,0 @@
-import 'package:flutter/services.dart';
-import 'package:fast_rsa/model/bridge.pb.dart';
-import 'package:fast_rsa/rsa.dart';
-
-class Transaction {}

loc_chain_app/lib/util/transaction_manager.dart

@@ -0,0 +1,25 @@
+import 'package:fast_rsa/model/bridge.pb.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:sqflite/sqflite.dart';
+import 'package:fast_rsa/rsa.dart';
+
+import 'dart:io';
+
+class Transaction {
+  Transaction({required this.otherUserID}) {
+    SharedPreferences.getInstance().then((s) => _id = s.getString('id') ?? '0');
+  }
+  late final String _id;
+  final String otherUserID;
+  static Hash? makeTransactionHash() {}
+}
+
+class TransactionsDBManager {
+  static Future<Database> get _localFile async {
+    return openDatabase('transactions.db');
+  }
+
+  static Future<List<Transaction>?> readTransactions() async {}
+
+  static Future<void> writeKeyPair(KeyPair pair) async {}
+}

loc_chain_app/pubspec.lock

@@ -191,6 +191,48 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.0"
+  shared_preferences:
+    dependency: "direct main"
+    description:
+      name: shared_preferences
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.5"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
+  shared_preferences_macos:
+    dependency: transitive
+    description:
+      name: shared_preferences_macos
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -203,6 +245,20 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.8.0"
+  sqflite:
+    dependency: "direct main"
+    description:
+      name: sqflite
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0+3"
+  sqflite_common:
+    dependency: transitive
+    description:
+      name: sqflite_common
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0+2"
   stack_trace:
     dependency: transitive
     description:
@@ -224,6 +280,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.0"
+  synchronized:
+    dependency: transitive
+    description:
+      name: synchronized
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "3.0.0"
   term_glyph:
     dependency: transitive
     description:
@@ -268,4 +331,4 @@ packages:
     version: "0.2.0"
 sdks:
   dart: ">=2.12.0 <3.0.0"
-  flutter: ">=1.20.0"
+  flutter: ">=1.24.0-10"

loc_chain_app/pubspec.yaml

@@ -24,12 +24,13 @@ dependencies:
   flutter:
     sdk: flutter
 
-
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
   cupertino_icons: ^1.0.2
   path_provider: ^2.0.1
   fast_rsa: ^1.4.0-nullsafety.4
+  shared_preferences: ^2.0.5
+  sqflite: ^2.0.0+3
 
 dev_dependencies:
   flutter_test: