Adds analysis options to Veggie Seasons (#98)

veggieseasons/lib/data/preferences.dart

@@ -32,19 +32,19 @@ class Preferences extends Model {
     return Set.from(_preferredCategories);
   }
 
-  void addPreferredCategory(VeggieCategory category) async {
+  Future<void> addPreferredCategory(VeggieCategory category) async {
     _preferredCategories.add(category);
     await _saveToSharedPrefs();
     notifyListeners();
   }
 
-  void removePreferredCategory(VeggieCategory category) async {
+  Future<void> removePreferredCategory(VeggieCategory category) async {
     _preferredCategories.remove(category);
     await _saveToSharedPrefs();
     notifyListeners();
   }
 
-  void setDesiredCalories(int calories) async {
+  Future<void> setDesiredCalories(int calories) async {
     _desiredCalories = calories;
     await _saveToSharedPrefs();
     notifyListeners();

veggieseasons/lib/screens/details.dart

@@ -23,7 +23,7 @@ class ServingInfoChart extends StatelessWidget {
   // value of this vitamin" data adjusted for the user's preferred calorie
   // target.
   Widget _buildVitaminText(int standardPercentage, Future<int> targetCalories) {
-    return FutureBuilder(
+    return FutureBuilder<int>(
       future: targetCalories,
       builder: (context, snapshot) {
         final target = snapshot?.data ?? 2000;
@@ -172,7 +172,7 @@ class InfoView extends StatelessWidget {
           Row(
             mainAxisSize: MainAxisSize.max,
             children: <Widget>[
-              FutureBuilder(
+              FutureBuilder<Set<VeggieCategory>>(
                 future: prefs.preferredCategories,
                 builder: (context, snapshot) {
                   return Text(
@@ -284,7 +284,7 @@ class _DetailsScreenState extends State<DetailsScreen> {
           Expanded(
             child: ListView(
               children: [
-                CupertinoSegmentedControl(
+                CupertinoSegmentedControl<int>(
                   children: {
                     0: Text('Facts & Info'),
                     1: Text('Trivia'),

veggieseasons/lib/screens/list.dart

@@ -13,7 +13,8 @@ import 'package:veggieseasons/styles.dart';
 import 'package:veggieseasons/widgets/veggie_card.dart';
 
 class ListScreen extends StatelessWidget {
-  Widget _generateVeggieRow(veggie, Preferences prefs, {bool inSeason = true}) {
+  Widget _generateVeggieRow(Veggie veggie, Preferences prefs,
+      {bool inSeason = true}) {
     return Padding(
       padding: EdgeInsets.only(left: 16, right: 16, bottom: 24),
       child: FutureBuilder<Set<VeggieCategory>>(

veggieseasons/lib/screens/settings.dart

@@ -126,7 +126,7 @@ class CalorieSettingsScreen extends StatelessWidget {
 }
 
 class SettingsScreen extends StatelessWidget {
-  Widget _buildCaloriesItem(BuildContext context, Preferences prefs) {
+  SettingsItem _buildCaloriesItem(BuildContext context, Preferences prefs) {
     return SettingsItem(
       label: 'Calorie Target',
       icon: SettingsIcon(
@@ -146,7 +146,7 @@ class SettingsScreen extends StatelessWidget {
         },
       ),
       onPress: () {
-        Navigator.of(context).push(
+        Navigator.of(context).push<void>(
           CupertinoPageRoute(
             builder: (context) => CalorieSettingsScreen(),
             title: 'Calorie Target',
@@ -156,7 +156,7 @@ class SettingsScreen extends StatelessWidget {
     );
   }
 
-  Widget _buildCategoriesItem(BuildContext context, Preferences prefs) {
+  SettingsItem _buildCategoriesItem(BuildContext context, Preferences prefs) {
     return SettingsItem(
       label: 'Preferred Categories',
       subtitle: 'What types of veggies you prefer!',
@@ -166,7 +166,7 @@ class SettingsScreen extends StatelessWidget {
       ),
       content: SettingsNavigationIndicator(),
       onPress: () {
-        Navigator.of(context).push(
+        Navigator.of(context).push<void>(
           CupertinoPageRoute(
             builder: (context) => VeggieCategorySettingsScreen(),
             title: 'Preferred Categories',

veggieseasons/lib/widgets/close_button.dart

@@ -69,12 +69,12 @@ class _ColorChangingIconState
   }
 
   @override
-  void forEachTween(visitor) {
+  void forEachTween(TweenVisitor<dynamic> visitor) {
     _colorTween = visitor(
       _colorTween,
       widget.color,
-      (dynamic value) => ColorTween(begin: value),
-    );
+      (dynamic value) => ColorTween(begin: value as Color),
+    ) as ColorTween;
   }
 }
 

veggieseasons/lib/widgets/settings_group.dart

@@ -69,7 +69,7 @@ class SettingsGroup extends StatelessWidget {
     this.header,
     this.footer,
   })  : assert(items != null),
-        assert(items.length > 0);
+        assert(items.isNotEmpty);
 
   final List<SettingsItem> items;
   final Widget header;

veggieseasons/lib/widgets/veggie_card.dart

@@ -143,7 +143,7 @@ class VeggieCard extends StatelessWidget {
   Widget build(BuildContext context) {
     return PressableCard(
       onPressed: () {
-        Navigator.of(context).push(CupertinoPageRoute(
+        Navigator.of(context).push<void>(CupertinoPageRoute(
           builder: (context) => DetailsScreen(veggie.id),
           fullscreenDialog: true,
         ));

veggieseasons/lib/widgets/veggie_headline.dart

@@ -68,7 +68,7 @@ class VeggieHeadline extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return GestureDetector(
-      onTap: () => Navigator.of(context).push(CupertinoPageRoute(
+      onTap: () => Navigator.of(context).push<void>(CupertinoPageRoute(
             builder: (context) => DetailsScreen(veggie.id),
             fullscreenDialog: true,
           )),