DropdownButtonFormField<T> class Null safety

A convenience widget that makes a DropdownButton into a FormField.

Inheritance

Constructors

Creates a DropdownButton widget that is a FormField, wrapped in an InputDecorator. [...]

Properties

autovalidate bool
Used to enable/disable auto validation and update their error text.
@Deprecated('Use autovalidateMode parameter which provides more specific ' 'behavior related to auto validation. ' 'This feature was deprecated after v1.19.0.'), final, inherited
autovalidateMode AutovalidateMode
Used to enable/disable this form field auto validation and update its error text. [...]
final, inherited
builder FormFieldBuilder<T>
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.
final, inherited
decoration InputDecoration
The decoration to show around the dropdown button form field. [...]
final
enabled bool
Whether the form is able to receive user input. [...]
final, inherited
hashCode int
The hash code for this object. [...]
@nonVirtual, read-only, inherited
initialValue → T?
An optional value to initialize the form field to, or null otherwise.
final, inherited
key Key?
Controls how one widget replaces another widget in the tree. [...]
final, inherited
onChanged ValueChanged<T?>?
Called when the user selects an item. [...]
final
onSaved FormFieldSetter<T>?
An optional method to call with the final value when the form is saved via FormState.save.
final, inherited
restorationId String?
Restoration ID to save and restore the state of the form field. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
validator FormFieldValidator<T>?
An optional method that validates an input. Returns an error string to display if the input is invalid, or null otherwise. [...]
final, inherited

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree. [...]
inherited
createState() FormFieldState<T>
Creates the mutable state for this widget at a given location in the tree. [...]
override
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep. [...]
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) String
A string representation of this object. [...]
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants. [...]
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object. [...]
inherited
toStringShort() String
A short, textual description of this widget.
inherited

Operators

operator ==(Object other) bool
The equality operator. [...]
@nonVirtual, inherited