Padding class

A widget that insets its child by the given padding.

When passing layout constraints to its child, padding shrinks the constraints by the given padding, causing the child to layout at a smaller size. Padding then sizes itself to its child's size, inflated by the padding, effectively creating empty space around the child.

{@tool snippet}

This snippet creates "Hello World!" Text inside a Card that is indented by sixteen pixels in each direction.

const Card(
  child: Padding(
    padding: EdgeInsets.all(16.0),
    child: Text('Hello World!'),
  ),
)

{@end-tool}

Design discussion

Why use a Padding widget rather than a Container with a Container.padding property?

There isn't really any difference between the two. If you supply a Container.padding argument, Container builds a Padding widget for you.

Container doesn't implement its properties directly. Instead, Container combines a number of simpler widgets together into a convenient package. For example, the Container.padding property causes the container to build a Padding widget and the Container.decoration property causes the container to build a DecoratedBox widget. If you find Container convenient, feel free to use it. If not, feel free to build these simpler widgets in whatever combination meets your needs.

In fact, the majority of widgets in Flutter are combinations of other simpler widgets. Composition, rather than inheritance, is the primary mechanism for building up widgets.

See also:

• EdgeInsets, the class that is used to describe the padding dimensions.
• AnimatedPadding, which animates changes in padding over a given duration.
• SliverPadding, the sliver equivalent of this widget.
• The catalog of layout widgets.

Inheritance

• Object
• DiagnosticableTree
• Widget
• StatelessWidget
• Padding

Constructors

Padding({Key? key, required EdgeInsetsGeometry padding, Widget? child})

Creates a widget that insets its child.

const

Properties

child → Widget?

The widget below this widget in the tree.

final

hashCode → int

The hash code for this object.

no setter, inherited

key → Key?

Controls how one widget replaces another widget in the tree.

final, inherited

padding → EdgeInsetsGeometry

The amount of space by which to inset the child.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, 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.

inherited

debugFillProperties(DiagnosticPropertiesBuilder properties) → void

Add additional properties associated with the node.

inherited

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent 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, int wrapWidth = 65}) → 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.

inherited