feat: add multiple choice form field

CHANGELOG.md

@@ -142,3 +142,6 @@
 ## 6.4.0 - June 28th 2024
 - Added `FlutterFormInputDropdown` for dropdown selection
 - Added style property to `FlutterFormInputEmail`
+
+## 6.5.0 - July 1st 2024
+- Added `FlutterFormMultipleChoice` for multiple choice selection

lib/src/widgets/input/input_types/input_types.dart

@@ -15,3 +15,4 @@ export 'input_phone.dart';
 export 'input_plain_text.dart';
 export 'input_slider/input_slider.dart';
 export 'input_switch/input_switch.dart';
+export 'multiple_choice.dart';

lib/src/widgets/input/input_types/multiple_choice.dart

@@ -0,0 +1,159 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_form_wizard/flutter_form.dart';
+
+class FlutterFormInputMultipleChoice extends FlutterFormInputWidget<String> {
+  /// Creates a [FlutterFormInputMultipleChoice].
+  ///
+  /// The [controller], [options], [builder], [validationMessage] parameters
+  /// are required.
+  /// The [key], [focusNode], [label] are optional.
+  const FlutterFormInputMultipleChoice({
+    required super.controller,
+    required this.options,
+    required this.builder,
+    required this.validationMessage,
+    super.focusNode,
+    super.label,
+    super.key,
+    this.mainAxisExtent,
+    this.childAspectRatio = 1,
+    this.mainAxisSpacing = 0,
+    this.crossAxisSpacing = 0,
+    this.crossAxisCount = 3,
+    this.height,
+    this.shrinkwrap = true,
+    this.validator,
+  });
+
+  final List<String> options;
+  final double? mainAxisExtent;
+  final double childAspectRatio;
+  final double mainAxisSpacing;
+  final double crossAxisSpacing;
+  final int crossAxisCount;
+  final double? height;
+  final bool shrinkwrap;
+  final Widget Function(
+    BuildContext context,
+    int index,
+    ValueNotifier<int?> selectedIndex,
+    FlutterFormInputController controller,
+    List<String> options,
+    FormFieldState<String> state,
+  ) builder;
+  final String? Function(String? value, String validationMessage)? validator;
+  final String validationMessage;
+
+  @override
+  Widget build(BuildContext context) {
+    super.registerController(context);
+    var selectedIndex = ValueNotifier<int?>(null);
+
+    return FormField<String>(
+      onSaved: controller.onSaved,
+      validator: (value) =>
+          validator?.call(value, validationMessage) ??
+          controller.onValidate(value, validationMessage),
+      builder: (state) => SizedBox(
+        height: height,
+        child: Column(
+          children: [
+            GridView.builder(
+              physics: const NeverScrollableScrollPhysics(),
+              itemCount: options.length,
+              shrinkWrap: shrinkwrap,
+              gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
+                mainAxisExtent: mainAxisExtent,
+                childAspectRatio: childAspectRatio,
+                mainAxisSpacing: mainAxisSpacing,
+                crossAxisSpacing: crossAxisSpacing,
+                crossAxisCount: crossAxisCount,
+              ),
+              itemBuilder: (context, index) => ListenableBuilder(
+                listenable: selectedIndex,
+                builder: (context, widget) => builder.call(
+                  context,
+                  index,
+                  selectedIndex,
+                  controller,
+                  options,
+                  state,
+                ),
+              ),
+            ),
+            if (state.hasError)
+              Text(
+                state.errorText!,
+                style: const TextStyle(
+                  color: Color(0xFFAD3645),
+                  fontSize: 14.0,
+                  fontWeight: FontWeight.bold,
+                ),
+              )
+            else
+              const SizedBox.shrink(),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class FlutterFormInputMultipleChoiceController
+    implements FlutterFormInputController<String> {
+  /// Creates a [FlutterFormInputMultipleChoiceController].
+  ///
+  /// The [id] parameter specifies the unique identifier for the controller.
+  /// The [mandatory] parameter specifies whether the input is mandatory.
+  /// The [value], [checkPageTitle], [checkPageDescription], [onChanged],
+  /// and [onSubmit] parameters are optional.
+  FlutterFormInputMultipleChoiceController({
+    required this.id,
+    this.mandatory = false,
+    this.value,
+    this.checkPageTitle,
+    this.checkPageDescription,
+    this.onChanged,
+    this.onSubmit,
+  });
+
+  @override
+  String? id;
+
+  @override
+  String? value;
+
+  @override
+  bool mandatory;
+
+  @override
+  String Function(String? value)? checkPageTitle;
+
+  @override
+  String Function(String? value)? checkPageDescription;
+
+  @override
+  void Function(String? value)? onChanged;
+
+  @override
+  void Function(String? value)? onSubmit;
+
+  @override
+  void onSaved(String? value) {
+    this.value = value;
+  }
+
+  @override
+  String? onValidate(
+    String? value,
+    String validationMessage,
+  ) {
+    if (mandatory) {
+      if (value == null || value.isEmpty) {
+        return validationMessage;
+      }
+    }
+
+    return null;
+  }
+}

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_form_wizard
 description: A new Flutter package project.
-version: 6.4.0
+version: 6.5.0
 homepage: https://github.com/Iconica-Development/flutter_form_wizard
 
 publish_to: none