SliverVisibility class

Whether to show or hide a sliver child.

By default, the visible property controls whether the sliver is included in the subtree or not; when it is not visible, the replacementSliver is included instead.

A variety of flags can be used to tweak exactly how the sliver is hidden. (Changing the flags dynamically is discouraged, as it can cause the sliver subtree to be rebuilt, with any state in the subtree being discarded. Typically, only the visible flag is changed dynamically.)

These widgets provide some of the facets of this one:

Using this widget is not necessary to hide children. The simplest way to hide a child is just to not include it. If a child must be given (e.g. because the parent is a StatelessWidget), then including a childless SliverToBoxAdapter instead of the child that would otherwise be included is typically more efficient than using SliverVisibility.

See also:

Inheritance

Constructors

SliverVisibility({Key? key, required Widget sliver, Widget replacementSliver = const SliverToBoxAdapter(), bool visible = true, bool maintainState = false, bool maintainAnimation = false, bool maintainSize = false, bool maintainSemantics = false, bool maintainInteractivity = false})
Control whether the given sliver is visible.
const
SliverVisibility.maintain({Key? key, required Widget sliver, Widget replacementSliver = const SliverToBoxAdapter(), bool visible = true})
Control whether the given sliver is visible.
const

Properties

hashCode int
The hash code for this object.
no setterinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
maintainAnimation bool
Whether to maintain animations within the sliver subtree when it is not visible.
final
maintainInteractivity bool
Whether to allow the sliver to be interactive when hidden.
final
maintainSemantics bool
Whether to maintain the semantics for the sliver when it is hidden (e.g. for accessibility).
final
maintainSize bool
Whether to maintain space for where the sliver would have been.
final
maintainState bool
Whether to maintain the State objects of the sliver subtree when it is not visible.
final
replacementSliver Widget
The widget to use when the sliver child is not visible, assuming that none of the maintain flags (in particular, maintainState) are set.
final
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
sliver Widget
The sliver to show or hide, as controlled by visible.
final
visible bool
Switches between showing the sliver or hiding it.
final

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.
override
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