Initial commit

.gitignore

@@ -0,0 +1,42 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# VS Code related
+.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.packages
+pubspec.lock
+.pub-cache/
+.pub/
+/build/
+
+# Web related
+lib/generated_plugin_registrant.dart
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Exceptions to above rules.
+!/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages

.metadata

@@ -0,0 +1,10 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: f7a6a7906be96d2288f5d63a5a54c515a6e987fe
+  channel: stable
+
+project_type: app

COPYING

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
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+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

README.md

@@ -0,0 +1,23 @@
+# Memor
+
+A simple reminder app.
+
+## Hacking
+
+Memor is developed in [Dart](https://dart.dev) using the
+[Flutter toolkit](https://flutter.dev). Please feel free to ask questions,
+request new features and contribute your ideas.
+
+## License
+
+Memor is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program.  If not, see <https://www.gnu.org/licenses/>.

android/.gitignore

@@ -0,0 +1,7 @@
+gradle-wrapper.jar
+/.gradle
+/captures/
+/gradlew
+/gradlew.bat
+/local.properties
+GeneratedPluginRegistrant.java

android/app/build.gradle

@@ -0,0 +1,62 @@
+def localProperties = new Properties()
+def localPropertiesFile = rootProject.file('local.properties')
+if (localPropertiesFile.exists()) {
+    localPropertiesFile.withReader('UTF-8') { reader ->
+        localProperties.load(reader)
+    }
+}
+
+def flutterRoot = localProperties.getProperty('flutter.sdk')
+if (flutterRoot == null) {
+    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
+}
+
+def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
+if (flutterVersionCode == null) {
+    flutterVersionCode = '1'
+}
+
+def flutterVersionName = localProperties.getProperty('flutter.versionName')
+if (flutterVersionName == null) {
+    flutterVersionName = '1.0'
+}
+
+apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+
+android {
+    compileSdkVersion 28
+
+    sourceSets {
+        main.java.srcDirs += 'src/main/kotlin'
+    }
+
+    lintOptions {
+        disable 'InvalidPackage'
+    }
+
+    defaultConfig {
+        applicationId "de.johrpan.memor"
+        minSdkVersion 16
+        targetSdkVersion 28
+        versionCode flutterVersionCode.toInteger()
+        versionName flutterVersionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig signingConfigs.debug
+        }
+    }
+}
+
+flutter {
+    source '../..'
+}
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+}

android/app/src/debug/AndroidManifest.xml

@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="de.johrpan.memor">
+    <!-- Flutter needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

android/app/src/main/AndroidManifest.xml

@@ -0,0 +1,44 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="de.johrpan.memor">
+    
+    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
+
+    <application
+        android:name="io.flutter.app.FlutterApplication"
+        android:label="Memor"
+        android:icon="@mipmap/ic_launcher"
+        android:roundIcon="@mipmap/ic_launcher_round">
+        <activity
+            android:name=".MainActivity"
+            android:launchMode="singleTop"
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme" />
+            <meta-data
+              android:name="io.flutter.embedding.android.SplashScreenDrawable"
+              android:resource="@drawable/launch_background" />
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+        
+        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
+            <intent-filter>
+                <action android:name="android.intent.action.BOOT_COMPLETED"></action>
+            </intent-filter>
+        </receiver>
+
+        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationReceiver" />
+    </application>
+</manifest>

android/app/src/main/kotlin/de/johrpan/memor/MainActivity.kt

@@ -0,0 +1,6 @@
+package de.johrpan.memor
+
+import io.flutter.embedding.android.FlutterActivity
+
+class MainActivity: FlutterActivity() {
+}

android/app/src/main/res/drawable-anydpi-v24/ic_memor.xml

@@ -0,0 +1,13 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="23.913044"
+    android:viewportHeight="23.913044"
+    android:tint="#FFFFFF">
+  <group android:translateX="0.95289856"
+      android:translateY="-0.04347826">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="m16.7712,1.8652c-0.6192,-0.0255 -1.2205,0.3151 -1.502,0.9121l-0.3066,0.6504C11.9058,2.7828 8.7097,4.2849 7.3239,7.2246L4.8434,12.4883 2.0212,13.502 1.57,14.4609l16.2813,7.6758 0.4512,-0.959 -1.0137,-2.8223 2.4824,-5.2637c1.3858,-2.9398 0.5112,-6.3591 -1.9316,-8.3066l0.3066,-0.6523C18.5214,3.3368 18.1824,2.3928 17.3864,2.0176 17.1874,1.9238 16.9776,1.8737 16.7712,1.8652ZM11.8044,6.1309 L12.2009,6.3184c-0.0939,2.6839 -0.1314,5.0824 -0.1133,7.1953l0.0977,0.0527 5.7012,-4.5684 0.2988,0.1406C17.2298,11.9735 16.3521,14.8015 15.5544,17.625c-0.1097,-0.0803 -0.3251,-0.1952 -0.6484,-0.3477 -0.2727,-0.1285 -0.4756,-0.2106 -0.6074,-0.2441 0.5635,-1.5388 1.2386,-3.539 2.0234,-6.002l-0.0449,-0.0273c-1.7579,1.3758 -3.5322,2.8448 -5.3223,4.4102l-0.2266,-0.1074c0.1229,-2.5131 0.1795,-4.8062 0.1719,-6.8809l-0.0527,-0.0254C9.4478,10.4402 8.2534,12.2124 7.2634,13.7168 7.1848,13.6512 7.0715,13.5835 6.9235,13.5137 6.7482,13.431 6.6101,13.3802 6.5095,13.3613 8.6233,10.5536 10.3888,8.1441 11.8044,6.1309ZM7.4802,18.3633c-0.469,0.995 -0.0438,2.1794 0.9512,2.6484 0.995,0.469 2.1794,0.0438 2.6484,-0.9512z"/>
+  </group>
+</vector>

android/app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -0,0 +1,12 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="39.34426"
+    android:viewportHeight="39.34426">
+  <group android:translateX="7.672131"
+      android:translateY="7.672131">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="m16.7712,1.8652c-0.6192,-0.0255 -1.2205,0.3151 -1.502,0.9121l-0.3066,0.6504C11.9058,2.7828 8.7097,4.2849 7.3239,7.2246L4.8434,12.4883 2.0212,13.502 1.57,14.4609l16.2813,7.6758 0.4512,-0.959 -1.0137,-2.8223 2.4824,-5.2637c1.3858,-2.9398 0.5112,-6.3591 -1.9316,-8.3066l0.3066,-0.6523C18.5214,3.3368 18.1824,2.3928 17.3864,2.0176 17.1874,1.9238 16.9776,1.8737 16.7712,1.8652ZM11.8044,6.1309 L12.2009,6.3184c-0.0939,2.6839 -0.1314,5.0824 -0.1133,7.1953l0.0977,0.0527 5.7012,-4.5684 0.2988,0.1406C17.2298,11.9735 16.3521,14.8015 15.5544,17.625c-0.1097,-0.0803 -0.3251,-0.1952 -0.6484,-0.3477 -0.2727,-0.1285 -0.4756,-0.2106 -0.6074,-0.2441 0.5635,-1.5388 1.2386,-3.539 2.0234,-6.002l-0.0449,-0.0273c-1.7579,1.3758 -3.5322,2.8448 -5.3223,4.4102l-0.2266,-0.1074c0.1229,-2.5131 0.1795,-4.8062 0.1719,-6.8809l-0.0527,-0.0254C9.4478,10.4402 8.2534,12.2124 7.2634,13.7168 7.1848,13.6512 7.0715,13.5835 6.9235,13.5137 6.7482,13.431 6.6101,13.3802 6.5095,13.3613 8.6233,10.5536 10.3888,8.1441 11.8044,6.1309ZM7.4802,18.3633c-0.469,0.995 -0.0438,2.1794 0.9512,2.6484 0.995,0.469 2.1794,0.0438 2.6484,-0.9512z"/>
+  </group>
+</vector>

android/app/src/main/res/drawable/launch_background.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="@android:color/white" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>

android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>

android/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>

android/app/src/main/res/values/ic_launcher_background.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="ic_launcher_background">#FFC107</color>
+</resources>

android/app/src/main/res/values/styles.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             Flutter draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">@android:color/white</item>
+    </style>
+</resources>

android/app/src/profile/AndroidManifest.xml

@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="de.johrpan.memor">
+    <!-- Flutter needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

android/build.gradle

@@ -0,0 +1,31 @@
+buildscript {
+    ext.kotlin_version = '1.3.50'
+    repositories {
+        google()
+        jcenter()
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:3.5.0'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+    }
+}
+
+allprojects {
+    repositories {
+        google()
+        jcenter()
+    }
+}
+
+rootProject.buildDir = '../build'
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+}
+subprojects {
+    project.evaluationDependsOn(':app')
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}

android/gradle.properties

@@ -0,0 +1,4 @@
+org.gradle.jvmargs=-Xmx1536M
+android.enableR8=true
+android.useAndroidX=true
+android.enableJetifier=true

android/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Fri Jun 23 08:50:38 CEST 2017
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.2-all.zip

android/settings.gradle

@@ -0,0 +1,15 @@
+include ':app'
+
+def flutterProjectRoot = rootProject.projectDir.parentFile.toPath()
+
+def plugins = new Properties()
+def pluginsFile = new File(flutterProjectRoot.toFile(), '.flutter-plugins')
+if (pluginsFile.exists()) {
+    pluginsFile.withReader('UTF-8') { reader -> plugins.load(reader) }
+}
+
+plugins.each { name, path ->
+    def pluginDirectory = flutterProjectRoot.resolve(path).resolve('android').toFile()
+    include ":$name"
+    project(":$name").projectDir = pluginDirectory
+}

lib/app.dart

@@ -0,0 +1,27 @@
+import 'package:flutter/material.dart';
+
+import 'home_screen.dart';
+
+/// A simple reminder app.
+///
+/// This has to be wrapped by a MemorBackend widget.
+class MemorApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      theme: ThemeData(
+        primaryColor: Colors.black,
+        accentColor: Colors.amber,
+        textSelectionColor: Colors.amber,
+        cursorColor: Colors.amber,
+        textSelectionHandleColor: Colors.amber,
+        colorScheme: ColorScheme.light(
+          primary: Colors.black,
+          secondary: Colors.amber,
+        ),
+        fontFamily: 'Libertinus Sans',
+      ),
+      home: HomeScreen(),
+    );
+  }
+}

lib/backend.dart

@@ -0,0 +1,176 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
+import 'package:path/path.dart' as p;
+import 'package:path_provider/path_provider.dart' as pp;
+import 'package:rxdart/rxdart.dart';
+
+import 'memo.dart';
+
+/// Widget for managing resources and state for Memor.
+///
+/// This should be near the top of the widget tree and provide other widgets
+/// with the globally shared resources and state.
+class MemorBackend extends StatefulWidget {
+  /// Retrieve the current backend state.
+  static MemorBackendState of(BuildContext context) => context
+      .dependOnInheritedWidgetOfExactType<_InheritedMemorBackend>()
+      .state;
+
+  /// The next widget down the tree.
+  ///
+  /// Descendants can get the current state by calling [of].
+  final Widget child;
+
+  MemorBackend({
+    @required this.child,
+  });
+
+  @override
+  MemorBackendState createState() => MemorBackendState();
+}
+
+class MemorBackendState extends State<MemorBackend> {
+  /// This will always contain the current list of memos.
+  ///
+  /// The memos will be ordered by their scheduled time.
+  final memos = BehaviorSubject.seeded(<Memo>[]);
+
+  /// Whether the backend is currently loading.
+  /// 
+  /// If this is true, the UI should not call backend methods.
+  bool loading = true;
+
+  static const _fileName = 'memos.json';
+
+  static const _notificationDetails = NotificationDetails(
+      AndroidNotificationDetails('memor', 'Memor', 'Memor reminders'),
+      IOSNotificationDetails());
+
+  final _notifications = FlutterLocalNotificationsPlugin();
+  File _file;
+
+  @override
+  void initState() {
+    super.initState();
+    _load();
+  }
+
+  /// Initialize resources and load memos from disk.
+  Future<void> _load() async {
+    await _notifications.initialize(InitializationSettings(
+        AndroidInitializationSettings('ic_memor'),
+        IOSInitializationSettings()));
+
+    final _baseDirectory = await pp.getApplicationDocumentsDirectory();
+    _file = File(p.join(_baseDirectory.path, _fileName));
+
+    if (await _file.exists()) {
+      final contents = await _file.readAsString();
+      final List<Map<String, dynamic>> json = List.from(jsonDecode(contents));
+
+      List<Memo> newMemos = [];
+      for (final memoJson in json) {
+        newMemos.add(Memo.fromJson(memoJson));
+      }
+
+      memos.add(newMemos);
+    }
+
+    setState(() {
+      loading = false;
+    });
+  }
+
+  /// Save memos to disk.
+  Future<void> _save() async {
+    final json = memos.value.map((m) => m.toJson()).toList();
+    await _file.writeAsString(jsonEncode(json));
+  }
+
+  /// Add a memo to the list.
+  ///
+  /// This will sort the list and update the stream afterwards. A notification
+  /// will be scheduled for the new memo.
+  Future<void> addMemo(Memo memo) async {
+    final List<Memo> newMemos = List.from(memos.value);
+    newMemos.add(memo);
+    newMemos.sort((m1, m2) => m1.scheduled.compareTo(m2.scheduled));
+    memos.add(newMemos);
+    await _schedule(memo);
+    await _save();
+  }
+
+  /// Delete a memo by its index.
+  ///
+  /// This will update the stream afterwards. The scheduled notification will
+  /// be canceled.
+  Future<void> deleteMemo(int index) async {
+    final List<Memo> newMemos = List.from(memos.value);
+    final memo = newMemos.removeAt(index);
+    memos.add(newMemos);
+    await _notifications.cancel(memo.id);
+    await _save();
+  }
+
+  /// Replace a memo by its index.
+  ///
+  /// This will sort the list and update the stream afterwards. The scheduled
+  /// notification for the old memo will be canceled and rescheduled.
+  Future<void> updateMemo(int index, Memo memo) async {
+    final List<Memo> newMemos = List.from(memos.value);
+    final oldMemo = newMemos[index];
+    await _notifications.cancel(oldMemo.id);
+    newMemos[index] = memo;
+    newMemos.sort((m1, m2) => m1.scheduled.compareTo(m2.scheduled));
+    memos.add(newMemos);
+    await _schedule(memo);
+    await _save();
+  }
+
+  /// Schedule a notification for a memo.
+  Future<void> _schedule(Memo memo) async {
+    _notifications.schedule(
+      memo.id,
+      'Reminder',
+      memo.text,
+      memo.scheduled,
+      _notificationDetails,
+      androidAllowWhileIdle: true,
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return _InheritedMemorBackend(
+      state: this,
+      child: widget.child,
+    );
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    memos.close();
+  }
+}
+
+/// Helper widget to pass the current backend state down the widget tree.
+class _InheritedMemorBackend extends InheritedWidget {
+  /// The current backend state.
+  final MemorBackendState state;
+
+  /// The next widget down the tree.
+  final Widget child;
+
+  _InheritedMemorBackend({
+    @required this.state,
+    @required this.child,
+  });
+
+  @override
+  bool updateShouldNotify(InheritedWidget oldWidget) => true;
+}

lib/date_utils.dart

@@ -0,0 +1,41 @@
+import 'package:flutter/material.dart';
+import 'package:intl/intl.dart';
+
+/// Utilities for handling DateTime objects.
+extension DateUtils on DateTime {
+  /// Create a new instance with identical values.
+  DateTime copy() => DateTime(
+        this.year,
+        this.month,
+        this.day,
+        this.hour,
+        this.minute,
+      );
+
+  /// Create a new instance with the same date but a different time.
+  DateTime copyWithTime(TimeOfDay time) => DateTime(
+        this.year,
+        this.month,
+        this.day,
+        time.hour,
+        time.minute,
+      );
+
+  /// Get a string representation of the represented day suitable for display.
+  String get dateString {
+    final now = DateTime.now();
+    if (this.year == now.year && this.month == now.month) {
+      if (this.day == now.day) {
+        return 'Today';
+      } else if (this.day == now.day + 1) {
+        return 'Tomorrow';
+      }
+    }
+
+    final format = DateFormat.yMd();
+    return format.format(this);
+  }
+
+  /// Get the time of day represented by this object.
+  TimeOfDay get timeOfDay => TimeOfDay.fromDateTime(this);
+}

lib/home_screen.dart

@@ -0,0 +1,121 @@
+import 'package:flutter/material.dart';
+
+import 'backend.dart';
+import 'date_utils.dart';
+import 'memo.dart';
+import 'memo_editor.dart';
+
+/// The Memor home screen.
+///
+/// The screen shows nothing more than a list of scheduled memos. They can be
+/// dismissed by swiping and edited by tapping.
+class HomeScreen extends StatelessWidget {
+  Future<Memo> _showMemoEditor(BuildContext context, [Memo memo]) async {
+    return await Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (context) => MemoEditor(
+          memo: memo,
+        ),
+        fullscreenDialog: true,
+      ),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final backend = MemorBackend.of(context);
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Memor'),
+      ),
+      body: backend.loading
+          ? Center(
+              child: CircularProgressIndicator(),
+            )
+          : StreamBuilder<List<Memo>>(
+              stream: backend.memos,
+              builder: (context, snapshot) {
+                if (snapshot.hasData) {
+                  final memos = snapshot.data;
+
+                  if (memos.isNotEmpty) {
+                    return ListView.builder(
+                      itemCount: memos.length,
+                      itemBuilder: (context, index) {
+                        final memo = memos[index];
+                        final scheduled = memo.scheduled;
+                        final dateString = scheduled.dateString;
+                        final timeOfDayString =
+                            scheduled.timeOfDay.format(context);
+
+                        return Dismissible(
+                          key: ValueKey(memo.id),
+                          secondaryBackground: Container(
+                            padding: const EdgeInsets.all(8.0),
+                            alignment: Alignment.centerRight,
+                            color: Colors.amber,
+                            child: const Icon(Icons.done),
+                          ),
+                          background: Container(
+                            padding: const EdgeInsets.all(8.0),
+                            alignment: Alignment.centerLeft,
+                            color: Colors.amber,
+                            child: const Icon(Icons.done),
+                          ),
+                          child: ListTile(
+                            title: Text(memo.text),
+                            subtitle: Text('$dateString at $timeOfDayString'),
+                            onTap: () async {
+                              final result =
+                                  await _showMemoEditor(context, memo);
+                              if (result != null) {
+                                await backend.updateMemo(index, result);
+                              }
+                            },
+                          ),
+                          onDismissed: (_) async {
+                            await backend.deleteMemo(index);
+                            Scaffold.of(context).showSnackBar(
+                              SnackBar(
+                                content: Text('Deleted "${memo.text}"'),
+                                action: SnackBarAction(
+                                  label: 'UNDO',
+                                  onPressed: () async {
+                                    await backend.addMemo(memo);
+                                  },
+                                ),
+                              ),
+                            );
+                          },
+                        );
+                      },
+                    );
+                  } else {
+                    return Center(
+                      child: Text(
+                        'No reminders scheduled',
+                        style: Theme.of(context).textTheme.headline6.copyWith(
+                              color: Colors.grey,
+                            ),
+                      ),
+                    );
+                  }
+                } else {
+                  return Container();
+                }
+              },
+            ),
+      floatingActionButton: FloatingActionButton(
+        child: const Icon(Icons.add),
+        onPressed: () async {
+          final result = await _showMemoEditor(context);
+          if (result != null) {
+            await backend.addMemo(result);
+          }
+        },
+      ),
+    );
+  }
+}

lib/main.dart

@@ -0,0 +1,12 @@
+import 'package:flutter/widgets.dart';
+
+import 'backend.dart';
+import 'app.dart';
+
+void main() {
+  runApp(
+    MemorBackend(
+      child: MemorApp(),
+    ),
+  );
+}

lib/memo.dart

@@ -0,0 +1,41 @@
+import 'dart:math';
+
+import 'package:meta/meta.dart';
+
+/// A simple memo.
+/// 
+/// This is the model to represent Memor's reminders.
+class Memo {
+  /// An unique ID for the memo.
+  /// 
+  /// This will be used for scheduling the notification. It will be generated,
+  /// if set to null.
+  final int id;
+
+  /// The actual memo set by the user.
+  final String text;
+
+  /// The date and time for the scheduled notification.
+  final DateTime scheduled;
+
+  static final _random = Random();
+  static int _generateId() => _random.nextInt(0xFFFFFFF);
+
+  Memo({
+    int id,
+    @required this.text,
+    @required this.scheduled,
+  }) : id = id ?? _generateId();
+
+  factory Memo.fromJson(Map<String, dynamic> json) => Memo(
+        id: json['id'],
+        text: json['text'],
+        scheduled: DateTime.parse(json['scheduled']),
+      );
+
+  Map<String, dynamic> toJson() => {
+        'id': id,
+        'text': text,
+        'scheduled': scheduled.toIso8601String(),
+      };
+}

lib/memo_editor.dart

@@ -0,0 +1,125 @@
+import 'package:flutter/material.dart';
+
+import 'memo.dart';
+import 'date_utils.dart';
+
+/// A screen for editing or creating a memo.
+/// 
+/// The new memo will be returned when popping the navigator. A return value of
+/// null indicates that the user has canceled the editor.
+class MemoEditor extends StatefulWidget {
+  /// The memo to edit.
+  /// 
+  /// A value of null indicates that the user will be creating a new memo.
+  final Memo memo;
+
+  MemoEditor({
+    this.memo,
+  });
+
+  @override
+  _MemoEditorState createState() => _MemoEditorState();
+}
+
+class _MemoEditorState extends State<MemoEditor> {
+  final _textController = TextEditingController();
+
+  DateTime _date;
+  TimeOfDay _time;
+
+  @override
+  void initState() {
+    super.initState();
+
+    if (widget.memo != null) {
+      _textController.text = widget.memo.text;
+      _date = widget.memo.scheduled.copy();
+      _time = TimeOfDay.fromDateTime(_date);
+    } else {
+      _date = DateTime.now().add(Duration(days: 1));
+      _time = TimeOfDay(
+        hour: 8,
+        minute: 0,
+      );
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(widget.memo != null ? 'Edit memo' : 'Add memo'),
+        actions: <Widget>[
+          FlatButton(
+            child: Text(
+              widget.memo != null ? 'SAVE' : 'CREATE',
+              style: theme.textTheme.button.copyWith(
+                color: theme.colorScheme.onPrimary,
+              ),
+            ),
+            onPressed: () {
+              Navigator.pop(
+                context,
+                Memo(
+                  text: _textController.text,
+                  scheduled: _date.copyWithTime(_time),
+                ),
+              );
+            },
+          ),
+        ],
+      ),
+      body: ListView(
+        children: <Widget>[
+          Padding(
+            padding: const EdgeInsets.all(16.0),
+            child: TextField(
+              controller: _textController,
+              maxLines: null,
+              decoration: InputDecoration(
+                border: OutlineInputBorder(),
+                labelText: 'Memo',
+              ),
+            ),
+          ),
+          ListTile(
+            title: Text('Date'),
+            subtitle: Text(_date.dateString),
+            onTap: () async {
+              final result = await showDatePicker(
+                context: context,
+                initialDate: _date,
+                firstDate: DateTime.now(),
+                lastDate: DateTime.now().add(Duration(days: 3560)),
+              );
+
+              if (result != null) {
+                setState(() {
+                  _date = result;
+                });
+              }
+            },
+          ),
+          ListTile(
+            title: Text('Time'),
+            subtitle: Text(_time.format(context)),
+            onTap: () async {
+              final result = await showTimePicker(
+                context: context,
+                initialTime: _time,
+              );
+
+              if (result != null) {
+                setState(() {
+                  _time = result;
+                });
+              }
+            },
+          ),
+        ],
+      ),
+    );
+  }
+}

pubspec.yaml

@@ -0,0 +1,27 @@
+name: memor
+description: A simple reminder app.
+version: 0.0.1
+
+environment:
+  sdk: ">=2.7.0 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  flutter_local_notifications:
+  intl:
+  meta:
+  path:
+  path_provider:
+  rxdart:
+
+flutter:
+  uses-material-design: true
+  fonts:
+  - family: Libertinus Sans
+    fonts:
+    - asset: fonts/libertinussans_regular.otf
+    - asset: fonts/libertinussans_bold.otf
+      weight: 700
+    - asset: fonts/libertinussans_italic.otf
+      style: italic