PreferredSize class
A widget with a preferred size.
This widget does not impose any constraints on its child, and it doesn't affect the child's layout in any way. It just advertises a preferred size which can be used by the parent.
See also:
- AppBar.bottom and Scaffold.appBar, which require preferred size widgets.
- PreferredSizeWidget, the interface which this widget implements to expose its preferred size.
- AppBar and TabBar, which implement PreferredSizeWidget.
- Inheritance
- Object
- Diagnosticable
- DiagnosticableTree
- Widget
- StatelessWidget
- PreferredSize
- Implemented types
Constructors
- PreferredSize({Key key, @required Widget child, @required Size preferredSize })
-
Creates a widget that has a preferred size.
const
Properties
- child → Widget
-
The widget below this widget in the tree. [...]
final
- preferredSize → Size
-
The size this widget would prefer if it were otherwise unconstrained. [...]
final
- hashCode → int
-
The hash code for this object. [...]
read-only, inherited
- key → Key
-
Controls how one widget replaces another widget in the tree. [...]
final, inherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
Methods
-
build(
BuildContext context) → Widget -
Describes the part of the user interface represented by this widget. [...]
override
-
createElement(
) → StatelessElement -
Creates a StatelessElement to manage this widget's location in the tree. [...]
inherited
-
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 toStringDeep. [...]
inherited
-
toString(
{DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String -
Returns 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 ==(
dynamic other) → bool -
The equality operator. [...]
inherited