Finish web prototype

moor/example_web/lib/database/database.dart

@@ -24,6 +24,22 @@ class Database extends _$Database {
   @override
   final int schemaVersion = 1;
 
+  @override
+  MigrationStrategy get migration {
+    return MigrationStrategy(
+      onCreate: (m) async => await m.createAllTables(),
+      beforeOpen: (engine, details) async {
+        if (details.wasCreated) {
+          // populate default data
+          await createTodoEntry('A simple todo list using moor web',
+              engine: engine);
+          await createTodoEntry('It even supports prepopulated data!',
+              engine: engine);
+        }
+      },
+    );
+  }
+
   Stream<List<Entry>> incompleteEntries() {
     return (select(todoEntries)..where((e) => not(e.done))).watch();
   }
@@ -37,11 +53,14 @@ class Database extends _$Database {
         .watch();
   }
 
-  Future createTodoEntry(String desc) {
-    return into(todoEntries).insert(TodoEntriesCompanion(content: Value(desc)));
+  Future createTodoEntry(String desc, {QueryEngine engine}) {
+    final resolved = engine ?? this;
+    return resolved
+        .into(todoEntries)
+        .insert(TodoEntriesCompanion(content: Value(desc)));
   }
 
   Future setCompleted(Entry entry, bool done) {
-    return update(todoEntries).write(entry.copyWith(done: done));
+    return update(todoEntries).replace(entry.copyWith(done: done));
   }
 }

moor/example_web/lib/database/database.g.dart

@@ -123,7 +123,7 @@ class $TodoEntriesTable extends TodoEntries
   GeneratedBoolColumn get done => _done ??= _constructDone();
   GeneratedBoolColumn _constructDone() {
     return GeneratedBoolColumn('done', $tableName, false,
-        defaultValue: const Constant(true));
+        defaultValue: const Constant(false));
   }
 
   @override

moor/example_web/lib/widgets/create_entry_bar.dart

@@ -23,6 +23,7 @@ class _CreateEntryBarState extends State<CreateEntryBar> {
         Expanded(
           child: TextField(
             controller: _controller,
+            onSubmitted: (_) => _submit(),
             decoration: InputDecoration(
               border: OutlineInputBorder(),
             ),
@@ -30,14 +31,18 @@ class _CreateEntryBarState extends State<CreateEntryBar> {
         ),
         IconButton(
           icon: Icon(Icons.add),
-          onPressed: () {
-            final text = _controller.text;
-            _controller.clear();
-
-            DatabaseProvider.provide(context).createTodoEntry(text);
-          },
+          onPressed: _submit,
         ),
       ],
     );
   }
+
+  void _submit() {
+    final text = _controller.text.trim();
+    _controller.clear();
+
+    if (text.isNotEmpty) {
+      DatabaseProvider.provide(context).createTodoEntry(text);
+    }
+  }
 }

moor/example_web/lib/widgets/home_screen.dart

@@ -1,3 +1,5 @@
+import 'dart:html';
+
 import 'package:example_web/main.dart';
 import 'package:example_web/widgets/entry_list.dart';
 import 'package:flutter_web/material.dart';
@@ -13,6 +15,40 @@ class HomeScreen extends StatelessWidget {
     return Scaffold(
       appBar: AppBar(
         title: const Text('Moor Web'),
+        actions: [
+          IconButton(
+            icon: Icon(Icons.info_outline),
+            onPressed: () {
+              showDialog(
+                context: context,
+                builder: (context) {
+                  return AlertDialog(
+                    title: const Text('Moor web'),
+                    content: const Text(
+                        'Simple demonstration of moor web: This whole page '
+                        'is a offline-capable Flutter app using sql.js to '
+                        'store data!'),
+                    actions: <Widget>[
+                      FlatButton(
+                        child: const Text('Moor'),
+                        onPressed: () {
+                          window.open('https://moor.simonbinder.eu/', 'Moor');
+                        },
+                      ),
+                      FlatButton(
+                        child: const Text('sql.js'),
+                        onPressed: () {
+                          window.open(
+                              'https://github.com/kripken/sql.js/', 'sql.js');
+                        },
+                      ),
+                    ],
+                  );
+                },
+              );
+            },
+          ),
+        ],
       ),
       body: Padding(
         padding: const EdgeInsets.symmetric(vertical: 16.0),

moor/lib/src/web/web_db.dart

@@ -204,12 +204,19 @@ class WebDatabase extends _DatabaseUser {
     );
     db.close();
 
+    if (version < 1) {
+      // assume version code 0 (default) to be null. Other parts of moor
+      // interpret a null version code as "the database was just created", so it
+      // fits.
+      version = null;
+    }
+
     final module = await initSqlJs();
     final restored = _restoreDb();
     _state.db = module.createDatabase(restored);
 
     if (upgradeNeeded) {
-      if (version == null || version < 1) {
+      if (version == null) {
         await databaseInfo.handleDatabaseCreation(executor: _runWithoutArgs);
       } else {
         await databaseInfo.handleDatabaseVersionChange(