Check if value is String, Iterable / Map then check length - required

Author: danvick

CHANGELOG.md

@@ -1,3 +1,6 @@
+## [3.0.0-beta.6] - 07-April-2019
+* Check if value candidate is of type String, Iterable or Map before checking length to determine empty in `FormValidators.required`
+
 ## [3.0.0-beta.6] - 09-April-2019
 * Properly hooked up SignaturePad to form, added onChanged to it
 * SignaturePad now returns `Uint8List` object from `png` image

lib/src/form_builder_validators.dart

@@ -6,8 +6,8 @@ class FormBuilderValidators {
   static FormFieldValidator required({
     String errorText = "This field cannot be empty.",
   }) {
-    return (val) {
-      if (val == null || val.isEmpty) {
+    return (val) { //FIXME: Change all val instances to valueCandidate
+      if (val == null || ((val is Iterable || val is String || val is Map) && val.length == 0)) {
         return errorText;
       }
     };

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_form_builder
 description: Package to build Material Form with components such as TextField (With number, url, email validation), DropDown, TypeAhead, Radios, Checkboxes
-version: 3.0.0-beta.6
+version: 3.0.0-beta.7
 author: Danvick Miller <[email protected]>
 homepage: https://github.com/danvick/flutter_form_builder
 

test/flutter_form_builder_test.dart

@@ -2,6 +2,14 @@ import 'package:test/test.dart';
 import 'package:flutter_form_builder/flutter_form_builder.dart';
 
 void main() {
+  test('FormBuilderValidators.required', () {
+    expect(FormBuilderValidators.required()("something long"), isNull);
+    expect(FormBuilderValidators.required()(DateTime.now()), isNull);
+    expect(FormBuilderValidators.required()(''), isNotNull);
+    expect(FormBuilderValidators.required()([]), isNotNull);
+    // expect(FormBuilderValidators.maxLength(5)(5), equals(null));
+  });
+
   test('FormBuilderValidators.maxLength', () {
     expect(FormBuilderValidators.maxLength(5)("something long"), equals("Value must have a length less than or equal to 5"));
     expect(FormBuilderValidators.maxLength(5)("two"), equals(null));