Key class

A Key is an identifier for Widgets, Elements and SemanticsNodes.

A new widget will only be used to update an existing element if its key is the same as the key of the current widget associated with the element.

Keys must be unique amongst the Elements with the same parent.

Subclasses of Key should either subclass LocalKey or GlobalKey.

See also the discussion at Widget.key.

Implementers
Annotations
  • @immutable

Constructors

Key(String value)
Construct a ValueKey<String> with the given String. [...]
const
factory
Key.empty()
Default constructor, used by subclasses. [...]
const

Properties

hashCode int
The hash code for this object. [...]
read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
toString() String
Returns a string representation of this object.
inherited

Operators

operator ==(dynamic other) bool
The equality operator. [...]
inherited