Refactor ShoppingList and Store - create and update now use the same form

lib/components/item_list.dart

@@ -20,7 +20,7 @@ class ItemList extends StatelessWidget {
 
     int getCount(item) {
       if (listType == 'shopping list') {
-        return item.itemIDs.length;
+        return item.itemIDs?.length;
       } else {
         return list.length;
       }

lib/db/database_manager.dart

@@ -42,5 +42,4 @@ class DatabaseManager {
     });
     return docRef;
   }
-
 }

lib/forms/shopping_list_form.dart

@@ -0,0 +1,81 @@
+import 'package:flutter/material.dart';
+import 'package:grocery_go/db/database_manager.dart';
+import 'package:grocery_go/db/shopping_list_dto.dart';
+
+class ShoppingListForm extends StatefulWidget {
+  final args;
+
+  ShoppingListForm({this.args});
+
+  @override
+  _ShoppingListFormState createState() => _ShoppingListFormState(args);
+}
+
+class _ShoppingListFormState extends State<ShoppingListForm> {
+
+  final args;
+  _ShoppingListFormState(this.args);
+
+  final formKey = GlobalKey<FormState>();
+  final DatabaseManager db = DatabaseManager();
+
+  final shoppingListFields = ShoppingListDTO();
+
+  String validateStringInput(String value) {
+    if (value.isEmpty) {
+      return 'Please enter a name';
+    } else return null;
+  }
+
+  void updateShoppingList(BuildContext context) async {
+    final formState = formKey.currentState;
+
+    if (formState.validate()) {
+      formKey.currentState.save();
+      shoppingListFields.date = DateTime.now().toString();
+
+      if (args != null) {
+        // preserve existing data from args
+        shoppingListFields.itemIDs = args.list.itemIDs;
+        shoppingListFields.id = args.list.id;
+        await db.updateShoppingList(args.list.id, shoppingListFields);
+      } else {
+        shoppingListFields.itemIDs = new List<String>();
+        await db.addShoppingList(shoppingListFields);
+      }
+
+      Navigator.of(context).pop();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+
+    return Form(
+      key: formKey,
+      child: Column(
+        children: [
+          Padding(
+            padding: EdgeInsets.all(8.0),
+            child: TextFormField(
+                autofocus: true,
+                initialValue: (args?.list?.name),
+                decoration: InputDecoration(
+                    labelText: 'List name',
+                    border: OutlineInputBorder()
+                ),
+                validator: (value) => validateStringInput(value),
+                onSaved: (value) {
+                  shoppingListFields.name = value;
+                }
+            ),
+          ),
+          RaisedButton(
+            onPressed: () => updateShoppingList(context),
+            child: Text('Save shopping list'),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/forms/store_form.dart

@@ -0,0 +1,93 @@
+import 'package:flutter/material.dart';
+import 'package:grocery_go/db/database_manager.dart';
+import 'package:grocery_go/db/store_dto.dart';
+
+class StoreForm extends StatefulWidget {
+  final args;
+
+  StoreForm({this.args});
+
+  @override
+  _StoreFormState createState() => _StoreFormState(args);
+}
+
+class _StoreFormState extends State<StoreForm> {
+
+  final args;
+  _StoreFormState(this.args);
+
+  final formKey = GlobalKey<FormState>();
+  final DatabaseManager db = DatabaseManager();
+
+  final storeFields = StoreDTO();
+
+  String validateStringInput(String value) {
+    if (value.isEmpty) {
+      return 'Please enter a name';
+    } else return null;
+  }
+
+  void updateStore(BuildContext context) async {
+    final formState = formKey.currentState;
+
+    if (formState.validate()) {
+      formKey.currentState.save();
+      storeFields.date = DateTime.now().toString();
+
+      if (args != null) {
+        storeFields.id = args.store.id;
+        await db.updateStore(args.store.id, storeFields);
+      } else {
+        await db.addStore(storeFields);
+      }
+
+      Navigator.of(context).pop();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+
+    return Form(
+      key: formKey,
+      child: Column(
+        children: [
+          Padding(
+            padding: EdgeInsets.all(8.0),
+            child: TextFormField(
+                autofocus: true,
+                initialValue: (args?.store?.name),
+                decoration: InputDecoration(
+                    labelText: 'Store name',
+                    border: OutlineInputBorder()
+                ),
+                validator: (value) => validateStringInput(value),
+                onSaved: (value) {
+                  storeFields.name = value;
+                }
+            ),
+          ),
+          Padding(
+            padding: EdgeInsets.all(8.0),
+            child: TextFormField(
+                autofocus: false,
+                initialValue: (args?.store?.address),
+                decoration: InputDecoration(
+                    labelText: 'Location (optional)',
+                    border: OutlineInputBorder()
+                ),
+                validator: (value) => validateStringInput(value),
+                onSaved: (value) {
+                  storeFields.address = value;
+                }
+            ),
+          ),
+          RaisedButton(
+            onPressed: () => updateStore(context),
+            child: Text('Save store'),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/views/existing_list.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:grocery_go/db/database_manager.dart';
-import 'package:grocery_go/db/shopping_list_dto.dart';
+import 'package:grocery_go/forms/shopping_list_form.dart';
 import 'package:grocery_go/models/shopping_list.dart';
 
 class ExistingListArguments {
@@ -19,80 +18,19 @@ class ExistingList extends StatefulWidget {
 class _ExistingListState extends State<ExistingList> {
   @override
   Widget build(BuildContext context) {
+
+    final ExistingListArguments args = ModalRoute.of(context).settings.arguments;
+
     return Scaffold(
       appBar: AppBar(
         title: Text("Edit shopping list"),
       ),
       body: Center(
         child: Padding(
           padding: EdgeInsets.all(20),
-          child: UpdateShoppingListForm(),
+          child: ShoppingListForm(args: args),
         ),
       ),
     );
   }
-}
-
-class UpdateShoppingListForm extends StatefulWidget {
-  @override
-  _UpdateShoppingListFormState createState() => _UpdateShoppingListFormState();
-}
-
-class _UpdateShoppingListFormState extends State<UpdateShoppingListForm> {
-  final formKey = GlobalKey<FormState>();
-  final DatabaseManager db = DatabaseManager();
-
-  final updateShoppingListFields = ShoppingListDTO();
-
-  String validateStringInput(String value) {
-    if (value.isEmpty) {
-      return 'Please enter a name';
-    } else return null;
-  }
-
-  void updateList(BuildContext context, list) async {
-    final formState = formKey.currentState;
-
-    if (formState.validate()) {
-      formKey.currentState.save();
-
-      // take the existing data
-      updateShoppingListFields.id = list.id;
-      updateShoppingListFields.itemIDs = list.itemIDs;
-      // update the last edited date
-      updateShoppingListFields.date = DateTime.now().toString();
-      await db.updateShoppingList(list.id, updateShoppingListFields);
-      Navigator.of(context).pop();
-    }
-  }
-
-  @override
-  Widget build(BuildContext context) {
-
-    final ExistingListArguments args = ModalRoute.of(context).settings.arguments;
-
-    return Form(
-      key: formKey,
-      child: Column(
-        children: [
-          TextFormField(
-            autofocus: true,
-            initialValue: args.list.name,
-            decoration: InputDecoration(
-                labelText: 'List name',
-                border: OutlineInputBorder()
-            ),
-            validator: (value) => validateStringInput(value),
-            onSaved: (value) {
-              updateShoppingListFields.name = value;
-            }
-          ),
-          RaisedButton(
-            onPressed: () => updateList(context, args.list),
-            child: Text('Update list'),
-          ),
-        ],
-      ),
-    );
-  }
 }