forme 2.5.0-alpha3+1

a powerful flutter form widget , for me,for you , renamed from form_builder

Screenshot

migrate from 2.1.x to 2.5.0

Forme 2.5.0 has lots of changes

1. support asyncValidator on ValueField
2. validate from FormeValueFieldController will return Future<String?>? instead of String?
3. validate from FormeController will return Future<Map<FormeValueFieldController>,String> instead of Map<FormeValueFieldController,String>
4. ValueField is not a subclass of FormField any more
5. you can easily detect whether a ValueField's value is nullable from ValueField's generic type, eg ValueField<String>'s value is a nonnull String , ValueField<String?>'s value is a nullable String
6. remove fieldValueListenable from FormeFieldController
7. remove lazyFieldValueListenable from FormeKey

Simple Usage

add dependency

flutter pub add forme

create forme

FormeKey key = FormeKey();// formekey is a global key , also  used to control form
Widget child = formContent;
Widget forme = Forme(
	key:key,
	child:child,
)

Forme Attributes

Attribute	Required	Type	Description
key	false	FormeKey	a global key, also used to control form
child	true	Widget	form content widget
readOnly	false	bool	whether form should be readOnly,default is false
onValueChanged	false	FormeValueChanged	listen form field's value change
initialValue	false	Map<String,dynamic>	initialValue , will override FormField's initialValue
onErrorChanged	false	FormeErrorChanged	listen form field's errorText change
onWillPop	false	WillPopCallback	Signature for a callback that verifies that it's OK to call Navigator.pop
quietlyValidate	false	bool	if this attribute is true , will not display default error text
onFocusChanged	false	FormeFocusChanged	listen form field's focus change

Differences Between Form and Forme

Forme is a form widget, but forme is not wrapped in a Form , because I don't want to refresh whole form after field's value changed or a validate performed , so it is a bit more complexable than Form.

Difference	Form	Forme
AutovalidateMode	support both Form and field	only support field
onChanged	won't fired if value changed via state.didChange or state.setValue	fired whenever field's value changed
rebuild strategy	when field value changed or perform a validation on field , all form fields will be rebuilded	only rebuild field that value changed or validated

Forme Fields

field type

-StatefulField
	- ValueField
	- CommonField

attributes supported by all stateful fields

Attribute	Required	Type	Description
name	true	String	field's id,should be unique in form
builder	true	FieldContentBuilder	build field content
readOnly	false	bool	whether field should be readOnly,default is false
model	true	FormeModel	FormeModel used to provider widget render data
listener	false	FormeFieldListener	user to listen onInitialed,onFocusChanged

attributes supported by all value fields

Attribute	Required	Type	Description
decoratorBuilder	false	FormeDecoratorBuilder	used to decorate a field
listener	false	FormeValueFieldListenable	user to listen onValueChanged,onErrorChanged,onValidate,onAsyncValidate,'onSaved'

currently supported fields

Name	Return Value	Nullable
FormeTextField	string	false
FormeDateTimeField	DateTime	true
FormeNumberField	num	true
FormeTimeField	TimeOfDay	true
FormeDateRangeField	DateTimeRange	true
FormeSlider	double	false
FormeRangeSlider	RangeValues	false
FormeFilterChip	List< T>	false
FormeChoiceChip	T	true
FormeSingleCheckbox	bool	false
FormeSingleSwitch	bool	false
FormeDropdownButton	T	true
FormeListTile	List< T>	false
FormeRadioGroup	T	true
FormeAsnycAutocompleteChip	List<T>	false
FormeAsnycAutocompleteText	T	true
FormeAutocompleteText	T	true

fields from other package

1. forme_cupertino_fields cupertino style fields

Forme Model

you can update a widget easily with FormeModel

eg: if you want to update labelText of a FormeTextField, you can do this :

FormeFieldController controller = formKey.field(fieldName);
controller.update(FormeTextFieldModel(decoration:InputDecoration(labelText:'New Label')));

if you want to update items of FormeDropdownButton:

controller.updateModel(FormeDropdownButtonModel<String>(
	icon: SizedBox(
	width: 14,
	height: 14,
	child: CircularProgressIndicator(),
)));
Future<List<DropdownMenuItem<String>>> future =
	Future.delayed(Duration(seconds: 2), () {
	return FormeUtils.toDropdownMenuItems(
		['java', 'dart', 'c#', 'python', 'flutter']);
	});
future.then((value) {
controller.updateModel(FormeDropdownButtonModel<String>(
	icon: Icon(Icons.arrow_drop_down), items: value));
});

update model will auto copywith old model's attribute

Custom way display error text

if default error text display can not fit your needs , you can implementing a custom error display via ValueField's onErrorChanged or FormeValueFieldController's errorTextListenable

don't forget to set Forme's quieltyValidate attribute to true

via onErrorChanged

onErrorChanged will triggered whenever errorText of field changes , it is suitable when you want to update a stateful field according to error state of field

eg: change border color when error state changes

FormeTextField(
	validator: validator,
	onErrorChanged: (m, a) {
		InputBorder border = OutlineInputBorder(
				borderRadius: BorderRadius.circular(30.0),
				borderSide: BorderSide(color: a == null ? Colors.green : Colors.red, width: 1));
		m.updateModel(FormeTextFieldModel(
			decoration: InputDecoration(
				focusedBorder: border, enabledBorder: border)));
	},
),

via errorTextListenable

errorTextListenable is more convenient than onErrorChanged sometimes.

eg: when your want to display an valid or invalid suffix icon according to error state of field, in onErrorChanged , update model will rebuild whole field, but with errorTextListenable, you can only rebuild the suffix icon, below is an example to do this:

suffixicon: Builder(
	builder: (context) {
		FormeValueFieldController<String, FormeModel>
			controller = FormeFieldController.of(context);
		return ValueListenableBuilder<FormeValidateError?>(
			valueListenable: controller.errorTextListenable,
			child: const IconButton(
				onPressed: null,
				icon: const Icon(
				Icons.check,
				color: Colors.green,
				)),
			builder: (context, errorText, child) {
			if (errorText == null)
				return SizedBox();
			else
				return errorText.isPresent
					? const IconButton(
						onPressed: null,
						icon: const Icon(
						Icons.error,
						color: Colors.red,
						))
					: child!;
			});
	},
),

listenable

there are five listenables in field

1. focusListenable
2. readOnlyListenable
3. errorTextListenable
4. valueListenable
5. modelListenable

get listenable

you can get focusListenable and readOnlyListenable from FormeFieldController, get valueListenable and errorTextListenable from FormeValueFieldController

FormeTextField(
	decoratorBuilder:FormeDecoratorBuilder(),//decorator is a part of field 
	mode:FormeTextFieldModel(
		decoration:InputDecoration(
			suffixIcon: Builder(builder: (context) {
				FormeFieldController controller = FormeFieldController.of(context);
				return ValueListenable<bool>(valueListenable:controller.		valueListenable,builder:(context,focus,child){
					if(focus) return Icon(Icons.clear);
					return SizedBox();
				})
			}),
		),
	),
)

validate

sync validate

sync validate is supported by FormeValidates

Validator Name	Support Type	When Valid	When Invalid
notNull	dynamic	value is not null	value is null
size	Iterable Map String	1. value is null 2. max & min is null 3. String's length or Collection's size is in [min,max]	String's length or Collection's size is not in [min,max]
min	num	1. value is null 2. value is bigger than min	value is smaller than min
max	num	1. value is null 2. value is smaller than max	value is bigger than max
notEmpty	Iterable Map String	1. value is not null 2. String's length or Collection's size is bigger than zero	1. value is null 2. String's length or Collection's size is zero
notBlank	String	1. value is null 2. value.trim()'s length is not null	value'length is zero after trimed
positive	num	1. value is null 2. value is bigger than zero	value is smaller than or equals zero
positiveOrZero	num	1. value is null 2. value is bigger than or equals zero	value is smaller than zero
negative	num	1. value null 2. value is smaller than zero	value is bigger than or equals zero
negativeOrZero	num	1. value null 2. value is smaller than or equals zero	value is bigger than zero
pattern	String	1. value null 2. value matches pattern	value does not matches pattern
email	String	1. value null 2. value is a valid email	value is not a valid email
url	String	1. value is null 2. value is empty or value is a valid url	value is not a valid url
range	num	1. value null 2. value is in range	value is out of range
equals	dynamic	1. value null 2. value is equals target value	value is not equals target value
any	T	any validators is valid	every validators is invalid
all	T	all validators is valid	any validators is invalid

when you use validators from FormeValidates , you must specific at least one errorText , otherwise errorText is an empty string

async validated

async validator is supported after Forme 2.2.0 , you can specific an asyncValidator on ValueField , the unique difference between validator and asyncValidator is asyncValidator return a Future and validator return a String

when perform a asyncValidator

if FormField.autovalidateMode is AutovalidateMode.disabled , asyncValidator will never be performed unless you call validate from FormeValueFieldController manually.

if you specific both validator and asyncValidator , asyncValidator will only be performed after validator passed.

after successful performed an async validator , async validator will not performed any more until field's value changed

debounce

you can specific a debounce on FormeValueFieldListener , debounce will not worked when you manually call validate on FormeValueFieldController

FormeKey Methods

whether form has a name field

bool hasField = formeKey.hasField(String name);

whether current form is readOnly

bool readOnly = formeKey.readOnly;

set readOnly

formeKey.readOnly = bool readOnly;

get field's controller

T controller = formeKey.field<T extends FormeFieldController>(String name);

get value field's controller

T controller = formeKey.valueField<T extends FormeValueFieldController>(String name);

get form data

Map<String, dynamic> data = formeKey.data;

validate

since 2.2.0 , this method will return a Future ranther than a Map

Future<Map<FormeValueFieldController,String>> errorsFuture = formKey.validate({bool quietly = false});

set form data

formeKey.data = Map<String,dynamic> data;

reset form

formeKey.reset();

save form

formeKey.save();

whether validate is quietly

bool quietlyValidate = formKey.quietlyValidate;

set quietlyValidate

formeKey.quieltyValidate = bool quietlyValidate;

Forme Field Methods

get forme controller

FormeController formeController = field.formeController;

get field's name

String name = field.name

whether current field is readOnly

bool readOnly = field.readOnly;

set readOnly on field

field.readOnly = bool readOnly;

whether current field is focused

bool hasFocus = field.hasFocus;

focus|unfocus current Field

field.requestFocus();
field.unfocus();

focus next

field.nextFocus();

set field model

field.model = FormeModel model;

update field model

field.updateModel(FormeModel model);

get field model

FormeModel model = field.model;

ensure field is visible in viewport

Future<void> result = field.ensureVisibe({Duration? duration,
      Curve? curve,
      ScrollPositionAlignmentPolicy? alignmentPolicy,
      double? alignment});

get focusListenable

ValueListenable<bool> focusListenable = field.focusListenable;

get readOnlyListenable

ValueListenable<bool> readOnlyListenable = field.readOnlyListenable;

get modelListenable

ValueListenable<FormeModel> modelListenable = field.modelListenable;

Forme Value Field Methods

FormeValueFieldController is extended FormeFieldController

get field value

dynamic value = valueField.value;

set field value

valueField.value = dynamic data;

reset field

valueField.reset();

validate field

since 2.2.0 , this method will return a Future ranther than a String

Future<String?>? errorFuture = valueField.validate({bool quietly = false});

get error

FormeValidateError? error = valueField.error;

get decorator controller

FormeDecoratorController decoratorController = valueField.decoratorController;

get errorTextListenable

ValueListenable<FormeValidateError?>  errorTextListenable = valueField.errorTextListenable;

get valueListenable

ValueListenable<dynamic> valueListenable = valueField.valueListenable;

get oldValue

dynamic value = valueField.oldValue;

build your field

1. create your FormeModel , if you don't need it , use FormeEmptyModel instead
2. create your ValueField<T,E> , T is your field return value's type, E is your FormeModel's type
3. if you want to create your custom State,extends ValueFieldState<T,E>

links below is some examples to help you to build your field

common field

1. https://github.com/wwwqyhme/forme/blob/main/lib/src/field/forme_visible.dart
2. https://github.com/wwwqyhme/forme/blob/main/lib/src/field/forme_flex.dart

value field

1. https://github.com/wwwqyhme/forme/blob/main/lib/src/field/forme_filter_chip.dart
2. https://github.com/wwwqyhme/forme/blob/main/lib/src/field/forme_radio_group.dart