LTextFormField class

A FormField that contains a TextField.

This is a convenience widget that wraps a TextField widget in a FormField.

A Form ancestor is not required. The Form simply makes it easier to save, reset, or validate multiple fields at once. To use without a Form, pass a GlobalKey to the constructor and use GlobalKey.currentState to save or reset the form field.

When a controller is specified, its TextEditingController.text defines the initialValue. If this FormField is part of a scrolling container that lazily constructs its children, like a ListView or a CustomScrollView, then a controller should be specified. The controller's lifetime should be managed by a stateful widget ancestor of the scrolling container.

If a controller is not specified, initialValue can be used to give the automatically generated controller an initial value.

Remember to dispose of the TextEditingController when it is no longer needed. This will ensure we discard any resources used by the object.

For a documentation about the various parameters, see TextField.

{@tool snippet}

Creates a LTextFormField with an InputDecoration and validator function.

If the user enters valid text, the TextField appears normally without any warnings to the user

If the user enters invalid text, the error message returned from the validator function is displayed in dark red underneath the input

  decoration: const InputDecoration(
    icon: Icon(Icons.person),
    hintText: 'What do people call you?',
    labelText: 'Name *',
  onSaved: (String value) {
    // This optional block of code can be used to run
    // code when the user saves the form.
  validator: (String value) {
    return value.contains('@') ? 'Do not use the @ char.' : null;


{@tool dartpad --template=stateful_widget_material} This example shows how to move the focus to the next field when the user presses the ENTER key.

import 'package:flutter/services.dart';
Widget build(BuildContext context) {
  return Material(
    child: Center(
      child: Shortcuts(
        shortcuts: <LogicalKeySet, Intent>{
          // Pressing enter on the field will now move to the next field.
        child: FocusTraversalGroup(
          child: Form(
            autovalidate: true,
            onChanged: () {
            child: Wrap(
              children: List<Widget>.generate(5, (int index) {
                return Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: ConstrainedBox(
                    constraints: BoxConstraints.tight(Size(200, 50)),
                    child: TextFormField(
                      onSaved: (String value) {
                        print('Value for field $index saved as "$value"');


See also:



LTextFormField({Key key, TextEditingController controller, String name, String initialValue, FocusNode focusNode, InputDecoration decoration = const InputDecoration(), TextInputType keyboardType, TextCapitalization textCapitalization = TextCapitalization.none, TextInputAction textInputAction, TextStyle style, TextStyle disabledStyle, StrutStyle strutStyle, TextDirection textDirection, TextAlign textAlign = TextAlign.start, TextAlignVertical textAlignVertical, bool autofocus = false, bool readOnly = false, ToolbarOptions toolbarOptions, bool showCursor, bool obscureText = false, bool autocorrect = true, SmartDashesType smartDashesType, SmartQuotesType smartQuotesType, bool enableSuggestions = true, bool autovalidate = false, bool maxLengthEnforced = true, int maxLines = 1, int minLines, bool expands = false, int maxLength, ValueChanged<String> onChanged, GestureTapCallback onTap, VoidCallback onEditingComplete, ValueChanged<String> onFieldSubmitted, FormFieldSetter<String> onSaved, List<LValidator<String>> validators, List<TextInputFormatter> inputFormatters, bool enabled = true, double cursorWidth = 2.0, Radius cursorRadius, Color cursorColor, Brightness keyboardAppearance, EdgeInsets scrollPadding = const EdgeInsets.all(20.0), bool enableInteractiveSelection = true, InputCounterWidgetBuilder buildCounter, ScrollPhysics scrollPhysics})
Creates a LFormField that contains a TextField.


autovalidate bool
If true, this form field will validate and update its error text immediately after every change. Otherwise, you must call LFormFieldState.validate to validate. If part of a LForm that auto-validates, this value will be ignored.
builder LFormFieldBuilder<String>
Function that returns the widget representing this form field. It is passed the form field state as input, containing the current value and validation state of this field.
controller TextEditingController
Controls the text being edited.
enabled bool
Whether the form is able to receive user input.
hashCode int
The hash code for this object.
initialValue String
An optional value to initialize the form field to, or null otherwise.
key Key
Controls how one widget replaces another widget in the tree.
name String
An optional field for serialization of the this field LFormState.serialize
onSaved LFormFieldSetter<String>
An optional method to call with the final value when the form is saved via
runtimeType Type
A representation of the runtime type of the object.
validators List<LValidator<String>>
An optional list of LValidator validators to validates an input. display error message if the input is invalid, or null otherwise.


createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
createState() → _LTextFormFieldState
Creates the mutable state for this widget at a given location in the tree.
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
toDiagnosticsNode({String name, DiagnosticsTreeStyle style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
toString({DiagnosticLevel minLevel =}) String
A string representation of this object.
toStringDeep({String prefixLineOne = '', String prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants.
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object.
toStringShort() String
A short, textual description of this widget.


operator ==(Object other) bool
The equality operator.