A scrolling list of variably-sized children.

Useful when you have a small, fixed number of children that you wish to arrange in a block layout and that might exceed the height of its container (and therefore need to scroll).

If you have a large number of children, or if you always expect this to need to scroll, consider using LazyBlock (if the children have variable height) or ScrollableList (if the children all have the same fixed height), as they avoid doing work for children that are not visible.

This widget is implemented using ScrollableViewport and BlockBody. If you have a single child, consider using ScrollableViewport directly.

See also:

Inheritance

Constructors

Block({Key key, List<Widget> children: const [], EdgeInsets padding, double initialScrollOffset, Axis scrollDirection: Axis.vertical, ViewportAnchor scrollAnchor: ViewportAnchor.start, ScrollListener onScrollStart, ScrollListener onScroll, ScrollListener onScrollEnd, Key scrollableKey })

Creates a scrollable array of children.

Properties

children List<Widget>

The children, all of which are materialized.

read-only
initialScrollOffset double

The scroll offset this widget should use when first created.

read-only
onScroll ScrollListener

Called whenever this widget's scroll offset changes.

read-only
onScrollEnd ScrollListener

Called whenever this widget stops scrolling.

read-only
onScrollStart ScrollListener

Called whenever this widget starts to scroll.

read-only
padding EdgeInsets

The amount of space by which to inset the children inside the viewport.

read-only
scrollableKey Key

The key to use for the underlying scrollable widget.

read-only
scrollAnchor ViewportAnchor

Whether to place first child at the start of the container or the last child at the end of the container, when the scrollable has not been scrolled and has no initial scroll offset.

read-only
scrollDirection Axis

The axis along which this widget should scroll.

read-only
hashCode int

Get a hash code for this object.

read-only, inherited
key Key

Controls how one widget replaces another widget in the tree.

read-only, inherited
runtimeType Type

A representation of the runtime type of the object.

read-only, inherited

Operators

operator ==(other) bool

The equality operator.

inherited

Methods

build(BuildContext context) Widget

Describes the part of the user interface represented by this widget.

createElement() StatelessElement

Creates a StatelessElement to manage this widget's location in the tree.

inherited
debugFillDescription(List<String> description) → void

Add additional information to the given description for use by toString.

inherited
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
toStringShort() String

A short, textual description of this widget.

inherited