Create the income and asset tables.

lib/db.dart

@@ -24,21 +24,45 @@ class DatabaseHelper {
     String path = join(documentsDirectory.path, "com_hyperling_expense.db");
     return await openDatabase(
       path,
-      version: 1,
+      version: 2,
       onCreate: _onCreate,
+      onUpgrade: _onUpgrade,
     );
   }
 
   Future _onCreate(Database db, int version) async {
     await db.execute("""
-        CREATE TABLE expense
+      CREATE TABLE expense
+        ( id INTEGER PRIMARY KEY
+        , name TEXT NOT NULL UNIQUE
+        , cost DOUBLE NOT NULL
+        , frequency TEXT NOT NULL
+        , description TEXT
+      )
+      """);
+  }
+
+  Future _onUpgrade(Database db, int previousVersion, int newVersion) async {
+    // Added in DB version 2.
+    if (previousVersion < 2 && newVersion >= 2) {
+      await db.execute("""
+        CREATE TABLE income
           ( id INTEGER PRIMARY KEY
           , name TEXT NOT NULL UNIQUE
-          , cost DOUBLE NOT NULL
+          , revenue DOUBLE NOT NULL
           , frequency TEXT NOT NULL
           , description TEXT
         )
         """);
+      await db.execute("""
+        CREATE TABLE asset
+          ( id INTEGER PRIMARY KEY
+          , name TEXT NOT NULL UNIQUE
+          , amount DOUBLE NOT NULL
+          , description TEXT
+        )
+        """);
+    }
   }
 
   /// Expense Section
@@ -81,8 +105,11 @@ class DatabaseHelper {
 
   Future<bool> checkExpenseNameExists(String name) async {
     Database db = await instance.db;
-    var expenses = await db.query("expense",
+    var expenses = await db.query(
-        where: "name = ?", whereArgs: [name],);
+      "expense",
+      where: "name = ?",
+      whereArgs: [name],
+    );
     return expenses.isNotEmpty;
   }
 

lib/models/asset.dart

@@ -0,0 +1,19 @@
+import '/models/tracked_type.dart';
+
+class Asset extends TrackedType {
+  static String amountText = "Amount";
+
+  Asset({
+    super.id,
+    required super.name,
+    required super.amount,
+    required super.description,
+  });
+
+  factory Asset.fromMap(Map<String, dynamic> json) => Asset(
+        id: json['id'],
+        name: json['name'],
+        amount: json['amount'],
+        description: json['description'],
+      );
+}

lib/models/expense.dart

@@ -21,4 +21,15 @@ class Expense extends RecurringTrackedType {
             .first,
         description: json['description'],
       );
+
+  @override
+  Map<String, dynamic> toMap() {
+    return {
+      'id': id,
+      'name': name,
+      'cost': amount,
+      'frequency': frequency.title,
+      'description': description,
+    };
+  }
 }

lib/models/income.dart

@@ -0,0 +1,35 @@
+import '/models/recurring_tracked_type.dart';
+import '/models/frequency.dart';
+
+class Income extends RecurringTrackedType {
+  static String amountText = "Revenue";
+
+  Income({
+    super.id,
+    required super.name,
+    required super.amount,
+    required super.frequency,
+    required super.description,
+  });
+
+  factory Income.fromMap(Map<String, dynamic> json) => Income(
+        id: json['id'],
+        name: json['name'],
+        amount: json['revenue'],
+        frequency: Frequency.values
+            .where((freq) => freq.title == json['frequency'])
+            .first,
+        description: json['description'],
+      );
+
+  @override
+  Map<String, dynamic> toMap() {
+    return {
+      'id': id,
+      'name': name,
+      'revenue': amount,
+      'frequency': frequency.title,
+      'description': description,
+    };
+  }
+}

lib/pages/expense.dart

@@ -289,15 +289,15 @@ class _ExpenseInputDialogState extends State<ExpenseInputDialog> {
                           if (value == null || value.isEmpty) {
                             return "${Expense.amountText} must be provided.";
                           }
+                          if (double.tryParse(value) == null) {
+                            return "${Expense.amountText} must be a valid number.";
+                          }
                           if (double.parse(value) < 0) {
                             return "Please use the Income page rather than having negative expenses.";
                           }
                           if (double.parse(value) < 0.01) {
                             return "${Expense.amountText} must be one hundreth (0.01) or higher.";
                           }
-                          if (double.tryParse(value) == null) {
-                            return "${Expense.amountText} must be a valid number.";
-                          }
                           return null;
                         },
                         onSaved: (value) {