Fleshes out settings screen with groups, items, and navigation (#43)

veggieseasons/lib/data/local_veggie_provider.dart

@@ -228,7 +228,7 @@ class LocalVeggieProvider {
       name: 'Squash',
       imageAssetPath: 'assets/images/squash.jpg',
       category: VeggieCategory.gourd,
-      shortDescription: 'Bigger and heartier than summer squashes.',
+      shortDescription: 'Just slather them in butter and pop \'em in the oven.',
       accentColor: Color(0x40dbb721),
       seasons: [Season.winter, Season.autumn],
     ),

veggieseasons/lib/data/preferences.dart

@@ -68,12 +68,14 @@ class Preferences extends Model {
     final prefs = await SharedPreferences.getInstance();
     _desiredCalories = prefs.getInt(_caloriesKey) ?? 2000;
     _preferredCategories.clear();
-    final names = prefs.getString(_preferredCategoriesKey) ?? '';
+    final names = prefs.getString(_preferredCategoriesKey);
 
-    for (final name in names.split(',')) {
+    if (names != null) {
-      final index = int.parse(name) ?? 0;
+      for (final name in names.split(',')) {
-      if (VeggieCategory.values[index] != null) {
+        final index = int.tryParse(name) ?? -1;
-        _preferredCategories.add(VeggieCategory.values[index]);
+        if (VeggieCategory.values[index] != null) {
+          _preferredCategories.add(VeggieCategory.values[index]);
+        }
       }
     }
 

veggieseasons/lib/screens/settings.dart

@@ -3,19 +3,208 @@
 // found in the LICENSE file.
 
 import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
+import 'package:scoped_model/scoped_model.dart';
+import 'package:veggieseasons/data/preferences.dart';
+import 'package:veggieseasons/data/veggie.dart';
 import 'package:veggieseasons/styles.dart';
+import 'package:veggieseasons/widgets/settings_group.dart';
+import 'package:veggieseasons/widgets/settings_item.dart';
 
-class SettingsScreen extends StatelessWidget {
+class VeggieCategorySettingsScreen extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
+    final model = ScopedModel.of<Preferences>(context, rebuildOnChange: true);
+    final currentPrefs = model.preferredCategories;
+
     return CupertinoPageScaffold(
       navigationBar: CupertinoNavigationBar(
-        middle: Text('Settings'),
+        middle: Text('Preferred Categories'),
+        previousPageTitle: 'Settings',
       ),
       backgroundColor: Styles.scaffoldBackground,
-      child: Center(
+      child: FutureBuilder<Set<VeggieCategory>>(
-        child: Text('Not yet implemented.'),
+        future: currentPrefs,
+        builder: (context, snapshot) {
+          final items = <SettingsItem>[];
+
+          for (final category in VeggieCategory.values) {
+            CupertinoSwitch toggle;
+
+            // It's possible that category data hasn't loaded from shared prefs
+            // yet, so display it if possible and fall back to disabled switches
+            // otherwise.
+            if (snapshot.hasData) {
+              toggle = CupertinoSwitch(
+                value: snapshot.data.contains(category),
+                onChanged: (value) {
+                  if (value) {
+                    model.addPreferredCategory(category);
+                  } else {
+                    model.removePreferredCategory(category);
+                  }
+                },
+              );
+            } else {
+              toggle = CupertinoSwitch(
+                value: false,
+                onChanged: null,
+              );
+            }
+
+            items.add(SettingsItem(
+              label: veggieCategoryNames[category],
+              content: toggle,
+            ));
+          }
+
+          return ListView(
+            children: [
+              SettingsGroup(
+                items: items,
+              ),
+            ],
+          );
+        },
+      ),
+    );
+  }
+}
+
+class CalorieSettingsScreen extends StatelessWidget {
+  static const max = 1000;
+  static const min = 2600;
+  static const step = 200;
+
+  @override
+  Widget build(BuildContext context) {
+    final model = ScopedModel.of<Preferences>(context, rebuildOnChange: true);
+
+    return CupertinoPageScaffold(
+      navigationBar: CupertinoNavigationBar(
+        previousPageTitle: 'Settings',
+      ),
+      backgroundColor: Styles.scaffoldBackground,
+      child: ListView(
+        children: [
+          FutureBuilder<int>(
+            future: model.desiredCalories,
+            builder: (context, snapshot) {
+              final steps = <SettingsItem>[];
+
+              for (int cals = max; cals < min; cals += step) {
+                steps.add(
+                  SettingsItem(
+                    label: cals.toString(),
+                    icon: SettingsIcon(
+                      icon: Styles.checkIcon,
+                      foregroundColor: snapshot.hasData && snapshot.data == cals
+                          ? CupertinoColors.activeBlue
+                          : Styles.transparentColor,
+                      backgroundColor: Styles.transparentColor,
+                    ),
+                    onPress: snapshot.hasData
+                        ? () => model.setDesiredCalories(cals)
+                        : null,
+                  ),
+                );
+              }
+
+              return SettingsGroup(
+                items: steps,
+                header: SettingsGroupHeader('Available calorie levels'),
+                footer: SettingsGroupFooter('These are used for serving '
+                    'calculations'),
+              );
+            },
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class SettingsScreen extends StatelessWidget {
+  Widget _buildCaloriesItem(BuildContext context, Preferences prefs) {
+    return SettingsItem(
+      label: 'Calorie Target',
+      icon: SettingsIcon(
+        backgroundColor: Styles.iconBlue,
+        icon: Styles.calorieIcon,
+      ),
+      content: FutureBuilder<int>(
+        future: prefs.desiredCalories,
+        builder: (context, snapshot) {
+          return Row(
+            children: <Widget>[
+              Text(snapshot.data?.toString() ?? ''),
+              SizedBox(width: 8.0),
+              SettingsNavigationIndicator(),
+            ],
+          );
+        },
+      ),
+      onPress: () {
+        Navigator.of(context).push(
+          CupertinoPageRoute(
+            builder: (context) => CalorieSettingsScreen(),
+            title: 'Calorie Target',
+          ),
+        );
+      },
+    );
+  }
+
+  Widget _buildCategoriesItem(BuildContext context, Preferences prefs) {
+    return SettingsItem(
+      label: 'Preferred Categories',
+      subtitle: 'What types of veggies you prefer!',
+      icon: SettingsIcon(
+        backgroundColor: Styles.iconGold,
+        icon: Styles.preferenceIcon,
+      ),
+      content: SettingsNavigationIndicator(),
+      onPress: () {
+        Navigator.of(context).push(
+          CupertinoPageRoute(
+            builder: (context) => VeggieCategorySettingsScreen(),
+            title: 'Preferred Categories',
+          ),
+        );
+      },
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final prefs = ScopedModel.of<Preferences>(context, rebuildOnChange: true);
+
+    return CupertinoPageScaffold(
+      child: Container(
+        color: Styles.scaffoldBackground,
+        child: CustomScrollView(
+          slivers: <Widget>[
+            CupertinoSliverNavigationBar(
+              largeTitle: Text('Settings'),
+            ),
+            SliverSafeArea(
+              top: false,
+              sliver: SliverList(
+                delegate: SliverChildListDelegate(
+                  <Widget>[
+                    SettingsGroup(
+                      items: [
+                        _buildCaloriesItem(context, prefs),
+                        _buildCategoriesItem(context, prefs),
+                      ],
+                    ),
+                  ],
+                ),
+              ),
+            ),
+          ],
+        ),
       ),
     );
   }

veggieseasons/lib/widgets/settings_group.dart

@@ -0,0 +1,132 @@
+// Copyright 2018 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/cupertino.dart';
+import 'package:veggieseasons/styles.dart';
+
+import 'settings_item.dart';
+
+// The widgets in this file present a group of Cupertino-style settings items to
+// the user. In the future, the Cupertino package in the Flutter SDK will
+// include dedicated widgets for this purpose, but for now they're done here.
+//
+// See https://github.com/flutter/flutter/projects/29 for more info.
+
+class SettingsGroupHeader extends StatelessWidget {
+  const SettingsGroupHeader(this.title);
+
+  final String title;
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: EdgeInsets.only(
+        left: 15.0,
+        right: 15.0,
+        bottom: 6.0,
+      ),
+      child: Text(
+        title.toUpperCase(),
+        style: TextStyle(
+          color: CupertinoColors.inactiveGray,
+          fontSize: 13.5,
+          letterSpacing: -0.5,
+        ),
+      ),
+    );
+  }
+}
+
+class SettingsGroupFooter extends StatelessWidget {
+  const SettingsGroupFooter(this.title);
+
+  final String title;
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: EdgeInsets.only(
+        left: 15.0,
+        right: 15.0,
+        top: 7.5,
+      ),
+      child: Text(
+        title,
+        style: TextStyle(
+          color: Styles.settingsGroupSubtitle,
+          fontSize: 13.0,
+          letterSpacing: -0.08,
+        ),
+      ),
+    );
+  }
+}
+
+class SettingsGroup extends StatelessWidget {
+  SettingsGroup({
+    @required this.items,
+    this.header,
+    this.footer,
+  })  : assert(items != null),
+        assert(items.length > 0);
+
+  final List<SettingsItem> items;
+  final Widget header;
+  final Widget footer;
+
+  @override
+  Widget build(BuildContext context) {
+    final dividedItems = <Widget>[items[0]];
+
+    for (int i = 1; i < items.length; i++) {
+      dividedItems.add(Container(
+        color: Styles.settingsLineation,
+        height: 0.3,
+      ));
+      dividedItems.add(items[i]);
+    }
+
+    final List<Widget> columnChildren = [];
+
+    if (header != null) {
+      columnChildren.add(header);
+    }
+
+    columnChildren.add(
+      Container(
+        decoration: BoxDecoration(
+          color: CupertinoColors.white,
+          border: Border(
+            top: const BorderSide(
+              color: Styles.settingsLineation,
+              width: 0.0,
+            ),
+            bottom: const BorderSide(
+              color: Styles.settingsLineation,
+              width: 0.0,
+            ),
+          ),
+        ),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.stretch,
+          children: dividedItems,
+        ),
+      ),
+    );
+
+    if (footer != null) {
+      columnChildren.add(footer);
+    }
+
+    return Padding(
+      padding: EdgeInsets.only(
+        top: header == null ? 35.0 : 22.0,
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: columnChildren,
+      ),
+    );
+  }
+}

veggieseasons/lib/widgets/settings_item.dart

@@ -0,0 +1,179 @@
+// Copyright 2018 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter/cupertino.dart';
+import 'package:veggieseasons/styles.dart';
+
+// The widgets in this file present a Cupertino-style settings item to the user.
+// In the future, the Cupertino package in the Flutter SDK will include
+// dedicated widgets for this purpose, but for now they're done here.
+//
+// See https://github.com/flutter/flutter/projects/29 for more info.
+
+typedef FutureOr<void> SettingsItemCallback();
+
+class SettingsNavigationIndicator extends StatelessWidget {
+  const SettingsNavigationIndicator({Key key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Icon(
+      CupertinoIcons.forward,
+      color: Styles.settingsMediumGray,
+      size: 21.0,
+    );
+  }
+}
+
+class SettingsIcon extends StatelessWidget {
+  const SettingsIcon({
+    @required this.icon,
+    this.foregroundColor = CupertinoColors.white,
+    this.backgroundColor = CupertinoColors.black,
+    Key key,
+  })  : assert(icon != null),
+        super(key: key);
+
+  final Color backgroundColor;
+  final Color foregroundColor;
+  final IconData icon;
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      decoration: BoxDecoration(
+        borderRadius: BorderRadius.circular(5.0),
+        color: backgroundColor,
+      ),
+      child: Center(
+        child: Icon(
+          icon,
+          color: foregroundColor,
+          size: 20.0,
+        ),
+      ),
+    );
+  }
+}
+
+class SettingsItem extends StatefulWidget {
+  const SettingsItem({
+    @required this.label,
+    this.icon,
+    this.content,
+    this.subtitle,
+    this.onPress,
+    Key key,
+  })  : assert(label != null),
+        super(key: key);
+
+  final String label;
+  final Widget icon;
+  final Widget content;
+  final String subtitle;
+  final SettingsItemCallback onPress;
+
+  @override
+  State<StatefulWidget> createState() => new SettingsItemState();
+}
+
+class SettingsItemState extends State<SettingsItem> {
+  bool pressed = false;
+
+  @override
+  Widget build(BuildContext context) {
+    List<Widget> rowChildren = [];
+
+    if (widget.icon != null) {
+      rowChildren.add(
+        Padding(
+          padding: const EdgeInsets.only(
+            left: 15.0,
+            bottom: 2.0,
+          ),
+          child: SizedBox(
+            height: 29.0,
+            width: 29.0,
+            child: widget.icon,
+          ),
+        ),
+      );
+    }
+
+    Widget titleSection;
+
+    if (widget.subtitle == null) {
+      titleSection = Padding(
+        padding: EdgeInsets.only(top: 1.5),
+        child: Text(widget.label),
+      );
+    } else {
+      titleSection = Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: <Widget>[
+          SizedBox(height: 8.5),
+          Text(widget.label),
+          SizedBox(height: 4.0),
+          Text(
+            widget.subtitle,
+            style: TextStyle(
+              fontSize: 12.0,
+              letterSpacing: -0.2,
+            ),
+          )
+        ],
+      );
+    }
+
+    rowChildren.add(
+      Expanded(
+        child: Padding(
+          padding: const EdgeInsets.only(
+            left: 15.0,
+          ),
+          child: titleSection,
+        ),
+      ),
+    );
+
+    rowChildren.add(
+      Padding(
+        padding: const EdgeInsets.only(right: 11.0),
+        child: widget.content ?? Container(),
+      ),
+    );
+
+    return AnimatedContainer(
+      duration: const Duration(milliseconds: 200),
+      color: pressed ? Styles.settingsItemPressed : Styles.transparentColor,
+      child: GestureDetector(
+        behavior: HitTestBehavior.opaque,
+        onTap: () async {
+          if (widget.onPress != null) {
+            setState(() {
+              pressed = true;
+            });
+            await widget.onPress();
+            Future.delayed(
+              Duration(milliseconds: 150),
+              () {
+                setState(() {
+                  pressed = false;
+                });
+              },
+            );
+          }
+        },
+        child: SizedBox(
+          height: widget.subtitle == null ? 44.0 : 57.0,
+          child: Row(
+            children: rowChildren,
+          ),
+        ),
+      ),
+    );
+  }
+}