Feature leading checkbox radio (#57)

* implement option for a leading checkbox

* implement option for a leading radio button

Author: SvenSchoene

lib/src/fields/form_builder_checkbox.dart

@@ -10,6 +10,7 @@ class FormBuilderCheckbox extends StatefulWidget {
   final InputDecoration decoration;
   final ValueChanged onChanged;
   final ValueTransformer valueTransformer;
+  final bool leadingInput;
 
   final Widget label;
 
@@ -22,6 +23,7 @@ class FormBuilderCheckbox extends StatefulWidget {
     this.decoration = const InputDecoration(),
     this.onChanged,
     this.valueTransformer,
+    this.leadingInput = false,
   });
 
   @override
@@ -47,6 +49,28 @@ class _FormBuilderCheckboxState extends State<FormBuilderCheckbox> {
     super.dispose();
   }
 
+  Widget _checkbox(FormFieldState<dynamic> field) {
+    return Checkbox(
+      value: field.value ?? false,
+      onChanged: _readonly
+          ? null
+          : (bool value) {
+              field.didChange(value);
+              if (widget.onChanged != null) widget.onChanged(value);
+            },
+    );
+  }
+
+  Widget _leading(FormFieldState<dynamic> field) {
+    if (widget.leadingInput) return _checkbox(field);
+    return null;
+  }
+
+  Widget _trailing(FormFieldState<dynamic> field) {
+    if (!widget.leadingInput) return _checkbox(field);
+    return null;
+  }
+
   @override
   Widget build(BuildContext context) {
     return FormField(
@@ -78,15 +102,8 @@ class _FormBuilderCheckboxState extends State<FormBuilderCheckbox> {
             isThreeLine: false,
             contentPadding: EdgeInsets.all(0.0),
             title: widget.label,
-            trailing: Checkbox(
-              value: field.value ?? false,
-              onChanged: _readonly
-                  ? null
-                  : (bool value) {
-                      field.didChange(value);
-                      if (widget.onChanged != null) widget.onChanged(value);
-                    },
-            ),
+            leading: _leading(field),
+            trailing: _trailing(field),
             onTap: _readonly
                 ? null
                 : () {

lib/src/fields/form_builder_radio.dart

@@ -10,6 +10,7 @@ class FormBuilderRadio extends StatefulWidget {
   final InputDecoration decoration;
   final ValueChanged onChanged;
   final ValueTransformer valueTransformer;
+  final bool leadingInput;
 
   final List<FormBuilderFieldOption> options;
 
@@ -22,6 +23,7 @@ class FormBuilderRadio extends StatefulWidget {
     this.decoration = const InputDecoration(),
     this.onChanged,
     this.valueTransformer,
+    this.leadingInput = false,
   });
 
   @override
@@ -47,6 +49,29 @@ class _FormBuilderRadioState extends State<FormBuilderRadio> {
     super.dispose();
   }
 
+  Widget _radio(FormFieldState<dynamic> field, int i) {
+    return Radio<dynamic>(
+      value: widget.options[i].value,
+      groupValue: field.value,
+      onChanged: _readonly
+          ? null
+          : (dynamic value) {
+              field.didChange(value);
+              if (widget.onChanged != null) widget.onChanged(value);
+            },
+    );
+  }
+
+  Widget _leading(FormFieldState<dynamic> field, int i) {
+    if (widget.leadingInput) return _radio(field, i);
+    return null;
+  }
+
+  Widget _trailing(FormFieldState<dynamic> field, int i) {
+    if (!widget.leadingInput) return _radio(field, i);
+    return null;
+  }
+
   @override
   Widget build(BuildContext context) {
     return FormField(
@@ -75,19 +100,10 @@ class _FormBuilderRadioState extends State<FormBuilderRadio> {
               dense: true,
               isThreeLine: false,
               contentPadding: EdgeInsets.all(0.0),
-              leading: null,
+              leading: _leading(field, i),
               title:
                   Text("${widget.options[i].label ?? widget.options[i].value}"),
-              trailing: Radio<dynamic>(
-                value: widget.options[i].value,
-                groupValue: field.value,
-                onChanged: _readonly
-                    ? null
-                    : (dynamic value) {
-                        field.didChange(value);
-                        if (widget.onChanged != null) widget.onChanged(value);
-                      },
-              ),
+              trailing: _trailing(field, i),
               onTap: _readonly
                   ? null
                   : () {

pubspec.lock

@@ -21,7 +21,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.8"
+    version: "2.2.0"
   boolean_selector:
     dependency: transitive
     description:
@@ -171,7 +171,7 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.3+1"
+    version: "0.12.5"
   meta:
     dependency: transitive
     description:
@@ -227,7 +227,7 @@ packages:
       name: pedantic
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.4.0"
+    version: "1.5.0"
   pool:
     dependency: transitive
     description:
@@ -248,7 +248,7 @@ packages:
       name: quiver
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.1"
+    version: "2.0.3"
   shelf:
     dependency: transitive
     description:
@@ -302,7 +302,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.4"
+    version: "1.5.5"
   stack_trace:
     dependency: transitive
     description:
@@ -316,7 +316,7 @@ packages:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.6.8"
+    version: "2.0.0"
   string_scanner:
     dependency: transitive
     description:
@@ -344,21 +344,21 @@ packages:
       name: test
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.3"
+    version: "1.6.3"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.2"
+    version: "0.2.5"
   test_core:
     dependency: transitive
     description:
       name: test_core
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.1+1"
+    version: "0.2.5"
   typed_data:
     dependency: transitive
     description:
@@ -409,5 +409,5 @@ packages:
     source: hosted
     version: "2.1.15"
 sdks:
-  dart: ">=2.1.0 <3.0.0"
+  dart: ">=2.2.0 <3.0.0"
   flutter: ">=0.1.4 <2.0.0"

pubspec.yaml

@@ -22,6 +22,6 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  test: 1.5.3
+  test: 1.6.3
 
 flutter: