refactor(lint): add new lint rules

analysis_options.yaml

@@ -1 +1,187 @@
 include: package:flutter_lints/flutter.yaml
+
+analyzer:
+  errors:
+    annotate_overrides: error
+    avoid_shadowing_type_parameters: warning
+    exhaustive_cases: warning
+    literal_only_boolean_expressions: warning
+    missing_required_param: warning
+    missing_return: warning
+    no_duplicate_case_values: error
+    only_throw_errors: error
+    override_on_non_overriding_member: error
+    unnecessary_overrides: error
+
+linter:
+  rules:
+    - always_declare_return_types
+    - annotate_overrides
+    - avoid_bool_literals_in_conditional_expressions
+    - avoid_catching_errors
+    - avoid_dynamic_calls
+    - avoid_empty_else
+    - avoid_escaping_inner_quotes
+    - avoid_field_initializers_in_const_classes
+    - avoid_final_parameters
+    - avoid_function_literals_in_foreach_calls
+    - avoid_implementing_value_types
+    - avoid_init_to_null
+    - avoid_js_rounded_ints
+    - avoid_null_checks_in_equality_operators
+    - avoid_print
+    - avoid_private_typedef_functions
+    - avoid_redundant_argument_values
+    - avoid_relative_lib_imports
+    - avoid_renaming_method_parameters
+    - avoid_return_types_on_setters
+    - avoid_returning_null_for_void
+    - avoid_returning_this
+    - avoid_setters_without_getters
+    - avoid_shadowing_type_parameters
+    - avoid_single_cascade_in_expression_statements
+    - avoid_slow_async_io
+    - avoid_type_to_string
+    - avoid_types_as_parameter_names
+    - avoid_unnecessary_containers
+    - avoid_unused_constructor_parameters
+    - avoid_void_async
+    - avoid_web_libraries_in_flutter
+    - await_only_futures
+    - camel_case_extensions
+    - camel_case_types
+    - cancel_subscriptions
+    - cascade_invocations
+    - cast_nullable_to_non_nullable
+    - close_sinks
+    - collection_methods_unrelated_type
+    - comment_references
+    - conditional_uri_does_not_exist
+    - constant_identifier_names
+    - control_flow_in_finally
+    - curly_braces_in_flow_control_structures
+    - depend_on_referenced_packages
+    - deprecated_consistency
+    - directives_ordering
+    - discarded_futures
+    - empty_catches
+    - empty_constructor_bodies
+    - empty_statements
+    - enable_null_safety
+    - eol_at_end_of_file
+    - exhaustive_cases
+    - file_names
+    - hash_and_equals
+    - implementation_imports
+    - iterable_contains_unrelated_type
+    - join_return_with_assignment
+    - leading_newlines_in_multiline_strings
+    - library_names
+    - library_prefixes
+    - library_private_types_in_public_api
+    - list_remove_unrelated_type
+    - literal_only_boolean_expressions
+    - missing_whitespace_between_adjacent_strings
+    - no_adjacent_strings_in_list
+    - no_duplicate_case_values
+    - no_leading_underscores_for_library_prefixes
+    - no_leading_underscores_for_local_identifiers
+    - no_logic_in_create_state
+    - no_runtimeType_toString
+    - non_constant_identifier_names
+    - noop_primitive_operations
+    - null_check_on_nullable_type_parameter
+    - null_closures
+    - omit_local_variable_types
+    - only_throw_errors
+    - overridden_fields
+    - package_api_docs
+    - package_names
+    - package_prefixed_library_names
+    - parameter_assignments
+    - prefer_adjacent_string_concatenation
+    - prefer_asserts_in_initializer_lists
+    - prefer_asserts_with_message
+    - prefer_collection_literals
+    - prefer_conditional_assignment
+    - prefer_const_constructors
+    - prefer_const_constructors_in_immutables
+    - prefer_const_declarations
+    - prefer_const_literals_to_create_immutables
+    - prefer_constructors_over_static_methods
+    - prefer_contains
+    - prefer_final_fields
+    - prefer_final_in_for_each
+    - prefer_final_locals
+    - prefer_for_elements_to_map_fromIterable
+    - prefer_function_declarations_over_variables
+    - prefer_generic_function_type_aliases
+    - prefer_if_elements_to_conditional_expressions
+    - prefer_if_null_operators
+    - prefer_initializing_formals
+    - prefer_inlined_adds
+    - prefer_interpolation_to_compose_strings
+    - prefer_is_empty
+    - prefer_is_not_empty
+    - prefer_is_not_operator
+    - prefer_iterable_whereType
+    - prefer_null_aware_method_calls
+    - prefer_null_aware_operators
+    - prefer_single_quotes
+    - prefer_spread_collections
+    - prefer_typing_uninitialized_variables
+    - prefer_void_to_null
+    - provide_deprecation_message
+    - recursive_getters
+    - require_trailing_commas
+    - sized_box_for_whitespace
+    - sized_box_shrink_expand
+    - slash_for_doc_comments
+    - sort_child_properties_last
+    - sort_unnamed_constructors_first
+    - test_types_in_equals
+    - throw_in_finally
+    - tighten_type_of_initializing_formals
+    - type_annotate_public_apis
+    - type_init_formals
+    - unawaited_futures
+    - unnecessary_await_in_return
+    - unnecessary_brace_in_string_interps
+    - unnecessary_const
+    - unnecessary_constructor_name
+    - unnecessary_getters_setters
+    - unnecessary_lambdas
+    - unnecessary_late
+    - unnecessary_new
+    - unnecessary_null_aware_assignments
+    - unnecessary_null_checks
+    - unnecessary_null_in_if_null_operators
+    - unnecessary_nullable_for_final_variable_declarations
+    - unnecessary_overrides
+    - unnecessary_parenthesis
+    - unnecessary_raw_strings
+    - unnecessary_statements
+    - unnecessary_string_escapes
+    - unnecessary_string_interpolations
+    - unnecessary_this
+    - unnecessary_to_list_in_spreads
+    - unrelated_type_equality_checks
+    - unsafe_html
+    - use_build_context_synchronously
+    - use_colored_box
+    - use_decorated_box
+    - use_enums
+    - use_full_hex_values_for_flutter_colors
+    - use_function_type_syntax_for_parameters
+    - use_is_even_rather_than_modulo
+    - use_key_in_widget_constructors
+    - use_late_for_private_fields_and_variables
+    - use_named_constants
+    - use_raw_strings
+    - use_rethrow_when_possible
+    - use_setters_to_change_properties
+    - use_string_buffers
+    - use_super_parameters
+    - use_to_and_as_if_applicable
+    - valid_regexps
+    - void_checks

example/lib/example_candidate_model.dart

@@ -14,29 +14,29 @@ class ExampleCandidateModel {
   });
 }
 
-List<ExampleCandidateModel> candidates = [
+final List<ExampleCandidateModel> candidates = [
   ExampleCandidateModel(
     name: 'One, 1',
     job: 'Developer',
     city: 'Areado',
-    color: [Color(0xFFFF3868), Color(0xFFFFB49A)],
+    color: const [Color(0xFFFF3868), Color(0xFFFFB49A)],
   ),
   ExampleCandidateModel(
     name: 'Two, 2',
     job: 'Manager',
     city: 'New York',
-    color: [Color(0xFF736EFE), Color(0xFF62E4EC)],
+    color: const [Color(0xFF736EFE), Color(0xFF62E4EC)],
   ),
   ExampleCandidateModel(
     name: 'Three, 3',
     job: 'Engineer',
     city: 'London',
-    color: [Color(0xFF2F80ED), Color(0xFF56CCF2)],
+    color: const [Color(0xFF2F80ED), Color(0xFF56CCF2)],
   ),
   ExampleCandidateModel(
     name: 'Four, 4',
     job: 'Designer',
     city: 'Tokyo',
-    color: [Color(0xFF0BA4E0), Color(0xFFA9E4BD)],
+    color: const [Color(0xFF0BA4E0), Color(0xFFA9E4BD)],
   ),
 ];

example/lib/example_card.dart

@@ -15,7 +15,7 @@ class ExampleCard extends StatelessWidget {
     return Container(
       clipBehavior: Clip.hardEdge,
       decoration: BoxDecoration(
-        borderRadius: BorderRadius.circular(10),
+        borderRadius: const BorderRadius.all(Radius.circular(10)),
         color: Colors.white,
         boxShadow: [
           BoxShadow(

example/lib/main.dart

@@ -4,10 +4,12 @@ import 'package:flutter/material.dart';
 import 'package:flutter_card_swiper/flutter_card_swiper.dart';
 
 void main() {
-  runApp(const MaterialApp(
+  runApp(
+    const MaterialApp(
       debugShowCheckedModeBanner: false,
       home: Example(),
-  ));
+    ),
+  );
 }
 
 class Example extends StatefulWidget {
@@ -39,29 +41,29 @@ class _ExamplePageState extends State<Example> {
               ),
             ),
             Padding(
-              padding: EdgeInsets.symmetric(vertical: 16.0),
+              padding: const EdgeInsets.symmetric(vertical: 16.0),
               child: Row(
                 mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                 children: [
                   FloatingActionButton(
                     onPressed: controller.swipe,
-                    child: Icon(Icons.rotate_right),
+                    child: const Icon(Icons.rotate_right),
                   ),
                   FloatingActionButton(
                     onPressed: controller.swipeLeft,
-                    child: Icon(Icons.keyboard_arrow_left),
+                    child: const Icon(Icons.keyboard_arrow_left),
                   ),
                   FloatingActionButton(
                     onPressed: controller.swipeRight,
-                    child: Icon(Icons.keyboard_arrow_right),
+                    child: const Icon(Icons.keyboard_arrow_right),
                   ),
                   FloatingActionButton(
                     onPressed: controller.swipeTop,
-                    child: Icon(Icons.keyboard_arrow_up),
+                    child: const Icon(Icons.keyboard_arrow_up),
                   ),
                   FloatingActionButton(
                     onPressed: controller.swipeBottom,
-                    child: Icon(Icons.keyboard_arrow_down),
+                    child: const Icon(Icons.keyboard_arrow_down),
                   ),
                 ],
               ),
@@ -73,6 +75,6 @@ class _ExamplePageState extends State<Example> {
   }
 
   void _swipe(int index, CardSwiperDirection direction) {
-    debugPrint("the card was swiped to the: " + direction.name);
+    debugPrint('the card $index was swiped to the: ${direction.name}');
   }
 }

lib/src/card_swiper.dart

@@ -52,9 +52,18 @@ class CardSwiper extends StatefulWidget {
     this.onSwipe,
     this.onEnd,
     this.direction = CardSwiperDirection.right,
-  })  : assert(maxAngle >= 0 && maxAngle <= 360),
+  })  : assert(
-        assert(threshold >= 1 && threshold <= 100),
+          maxAngle >= 0 && maxAngle <= 360,
-        assert(direction != CardSwiperDirection.none),
+          'maxAngle must be between 0 and 360',
+        ),
+        assert(
+          threshold >= 1 && threshold <= 100,
+          'threshold must be between 1 and 100',
+        ),
+        assert(
+          direction != CardSwiperDirection.none,
+          'direction must not be none',
+        ),
         super(key: key);
 
   @override
@@ -67,13 +76,12 @@ class _CardSwiperState extends State<CardSwiper>
   double _top = 0;
   double _total = 0;
   double _angle = 0;
-  double _maxAngle = 0;
   double _scale = 0.9;
   double _difference = 40;
 
   int _currentIndex = 0;
 
-  SwipeType _swipeTyp = SwipeType.none;
+  SwipeType _swipeType = SwipeType.none;
   bool _tapOnTop = false; //position of starting drag point on card
 
   late AnimationController _animationController;
@@ -84,6 +92,8 @@ class _CardSwiperState extends State<CardSwiper>
 
   CardSwiperDirection detectedDirection = CardSwiperDirection.none;
 
+  double get _maxAngle => widget.maxAngle * (pi / 180);
+
   bool get _isLastCard => _currentIndex == widget.cards.length - 1;
   int get _nextCardIndex => _isLastCard ? 0 : _currentIndex + 1;
 
@@ -91,80 +101,21 @@ class _CardSwiperState extends State<CardSwiper>
   void initState() {
     super.initState();
 
-    if (widget.controller != null) {
+    widget.controller?.addListener(_controllerListener);
-      //swipe widget from the outside
-      widget.controller!.addListener(() {
-        switch (widget.controller!.state) {
-          case CardSwiperState.swipe:
-            _swipe(context, widget.direction);
-            break;
-          case CardSwiperState.swipeLeft:
-            _swipe(context, CardSwiperDirection.left);
-            break;
-          case CardSwiperState.swipeRight:
-            _swipe(context, CardSwiperDirection.right);
-            break;
-          case CardSwiperState.swipeTop:
-            _swipe(context, CardSwiperDirection.top);
-            break;
-          case CardSwiperState.swipeBottom:
-            _swipe(context, CardSwiperDirection.bottom);
-            break;
-          default:
-            break;
-        }
-      });
-    }
 
-    if (widget.maxAngle > 0) {
+    _animationController = AnimationController(
-      _maxAngle = widget.maxAngle * (pi / 180);
+      duration: widget.duration,
-    }
+      vsync: this,
-
+    )
-    _animationController =
+      ..addListener(_animationListener)
-        AnimationController(duration: widget.duration, vsync: this);
+      ..addStatusListener(_animationStatusListener);
-    _animationController.addListener(() {
-      //when value of controller changes
-      if (_animationController.status == AnimationStatus.forward) {
-        setState(() {
-          _left = _leftAnimation.value;
-          _top = _topAnimation.value;
-          _scale = _scaleAnimation.value;
-          _difference = _differenceAnimation.value;
-        });
-      }
-    });
-
-    _animationController.addStatusListener((status) {
-      //when status of controller changes
-      if (status == AnimationStatus.completed) {
-        setState(() {
-          if (_swipeTyp == SwipeType.swipe) {
-            widget.onSwipe?.call(_currentIndex, detectedDirection);
-
-            if (_isLastCard) {
-              widget.onEnd?.call();
-              _currentIndex = 0;
-            } else {
-              _currentIndex++;
-            }
-          }
-          _animationController.reset();
-          _left = 0;
-          _top = 0;
-          _total = 0;
-          _angle = 0;
-          _scale = 0.9;
-          _difference = 40;
-          _swipeTyp = SwipeType.none;
-        });
-      }
-    });
   }
 
   @override
   void dispose() {
     super.dispose();
     _animationController.dispose();
+    widget.controller?.dispose();
   }
 
   @override
@@ -179,9 +130,10 @@ class _CardSwiperState extends State<CardSwiper>
                 clipBehavior: Clip.none,
                 fit: StackFit.expand,
                 children: [
-                    _backItem(constraints, _nextCardIndex),
+                  _backItem(constraints),
-                    _frontItem(constraints, _currentIndex)
+                  _frontItem(constraints),
-                  ]);
+                ],
+              );
             },
           ),
         );
@@ -189,7 +141,7 @@ class _CardSwiperState extends State<CardSwiper>
     );
   }
 
-  Widget _frontItem(BoxConstraints constraints, int index) {
+  Widget _frontItem(BoxConstraints constraints) {
     return Positioned(
       left: _left,
       top: _top,
@@ -198,7 +150,7 @@ class _CardSwiperState extends State<CardSwiper>
           angle: _angle,
           child: ConstrainedBox(
             constraints: constraints,
-            child: widget.cards[index],
+            child: widget.cards[_currentIndex],
           ),
         ),
         onTap: () {
@@ -208,8 +160,8 @@ class _CardSwiperState extends State<CardSwiper>
         },
         onPanStart: (tapInfo) {
           if (!widget.isDisabled) {
-            RenderBox renderBox = context.findRenderObject() as RenderBox;
+            final renderBox = context.findRenderObject()! as RenderBox;
-            Offset position = renderBox.globalToLocal(tapInfo.globalPosition);
+            final position = renderBox.globalToLocal(tapInfo.globalPosition);
 
             if (position.dy < renderBox.size.height / 2) _tapOnTop = true;
           }
@@ -237,7 +189,7 @@ class _CardSwiperState extends State<CardSwiper>
     );
   }
 
-  Widget _backItem(BoxConstraints constraints, int index) {
+  Widget _backItem(BoxConstraints constraints) {
     return Positioned(
       top: _difference,
       left: 0,
@@ -245,15 +197,76 @@ class _CardSwiperState extends State<CardSwiper>
         scale: _scale,
         child: ConstrainedBox(
           constraints: constraints,
-          child: widget.cards[index],
+          child: widget.cards[_nextCardIndex],
         ),
       ),
     );
   }
 
+  //swipe widget from the outside
+  void _controllerListener() {
+    switch (widget.controller!.state) {
+      case CardSwiperState.swipe:
+        _swipe(context, widget.direction);
+        break;
+      case CardSwiperState.swipeLeft:
+        _swipe(context, CardSwiperDirection.left);
+        break;
+      case CardSwiperState.swipeRight:
+        _swipe(context, CardSwiperDirection.right);
+        break;
+      case CardSwiperState.swipeTop:
+        _swipe(context, CardSwiperDirection.top);
+        break;
+      case CardSwiperState.swipeBottom:
+        _swipe(context, CardSwiperDirection.bottom);
+        break;
+      default:
+        break;
+    }
+  }
+
+  //when value of controller changes
+  void _animationListener() {
+    if (_animationController.status == AnimationStatus.forward) {
+      setState(() {
+        _left = _leftAnimation.value;
+        _top = _topAnimation.value;
+        _scale = _scaleAnimation.value;
+        _difference = _differenceAnimation.value;
+      });
+    }
+  }
+
+  //when the status of animation changes
+  void _animationStatusListener(AnimationStatus status) {
+    if (status == AnimationStatus.completed) {
+      setState(() {
+        if (_swipeType == SwipeType.swipe) {
+          widget.onSwipe?.call(_currentIndex, detectedDirection);
+
+          if (_isLastCard) {
+            widget.onEnd?.call();
+            _currentIndex = 0;
+          } else {
+            _currentIndex++;
+          }
+        }
+        _animationController.reset();
+        _left = 0;
+        _top = 0;
+        _total = 0;
+        _angle = 0;
+        _scale = 0.9;
+        _difference = 40;
+        _swipeType = SwipeType.none;
+      });
+    }
+  }
+
   void _calculateAngle() {
     if (_angle <= _maxAngle && _angle >= -_maxAngle) {
-      (_tapOnTop)
+      _tapOnTop
           ? _angle = (_maxAngle / 100) * (_left / 10)
           : _angle = (_maxAngle / 100) * (_left / 10) * -1;
     }
@@ -285,7 +298,7 @@ class _CardSwiperState extends State<CardSwiper>
   //moves the card away to the left or right
   void _swipeHorizontal(BuildContext context) {
     setState(() {
-      _swipeTyp = SwipeType.swipe;
+      _swipeType = SwipeType.swipe;
       _leftAnimation = Tween<double>(
         begin: _left,
         end: (_left == 0)
@@ -346,7 +359,7 @@ class _CardSwiperState extends State<CardSwiper>
   //moves the card away to the top or bottom
   void _swipeVertical(BuildContext context) {
     setState(() {
-      _swipeTyp = SwipeType.swipe;
+      _swipeType = SwipeType.swipe;
       _leftAnimation = Tween<double>(
         begin: _left,
         end: _left + _left,
@@ -381,7 +394,7 @@ class _CardSwiperState extends State<CardSwiper>
   //moves the card back to starting position
   void _goBack(BuildContext context) {
     setState(() {
-      _swipeTyp = SwipeType.back;
+      _swipeType = SwipeType.back;
       _leftAnimation = Tween<double>(
         begin: _left,
         end: 0,

lib/src/typedefs.dart

@@ -1,6 +1,10 @@
 import 'package:flutter_card_swiper/src/enums.dart';
 
 typedef CardSwiperOnSwipe = void Function(
-    int index, CardSwiperDirection direction);
+  int index,
+  CardSwiperDirection direction,
+);
+
 typedef CardSwiperOnEnd = void Function();
+
 typedef CardSwiperOnTapDisabled = void Function();