A virtual viewport onto a list of equally sized children.
ListViewport differs from LazyListViewport in that ListViewport uses an Iterable list of children. That makes ListViewport suitable for a large (but not extremely large or infinite) list of children.
ListViewport differs from LazyBlockViewport in that ListViewport requires each of its children to be the same size. That makes ListViewport more efficient but less flexible than LazyBlockViewport.
Prefer Viewport when there is only one child.
Used by ScrollableList.
See also:
- Mixes-in
- VirtualViewportFromIterable
Constructors
-
ListViewport({ExtentsChangedCallback onExtentsChanged, double scrollOffset: 0.0, Axis mainAxis: Axis.vertical, ViewportAnchor anchor: ViewportAnchor.start, @required double itemExtent, bool itemsWrap: false, EdgeInsets padding, Iterable<Widget> children: const
[] }) -
Creates a virtual viewport onto a list of equally sized children.
Properties
- children → Iterable<Widget>
-
read-only
- anchor → ViewportAnchor
-
Whether to place first child at the start of the container or the last child at the end of the container, when the viewport has not been offset.
read-only, inherited - hashCode → int
-
Get a hash code for this object.
read-only, inherited - itemExtent → double
-
The height of each item if
scrollDirectionis Axis.vertical, otherwise the width of each item.read-only, inherited - itemsWrap → bool
-
Whether the first item should be revealed after scrolling past the last item.
read-only, inherited - key → Key
-
Controls how one widget replaces another widget in the tree.
read-only, inherited - mainAxis → Axis
-
The direction in which the children are permitted to be larger than the viewport.
read-only, inherited - onExtentsChanged → ExtentsChangedCallback
-
Called when the interior or exterior dimensions of the viewport change.
read-only, inherited - padding → EdgeInsets
-
The amount of space by which to inset the children inside the viewport.
read-only, inherited - runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited - scrollOffset → double
-
The
startOffsetwithout taking thepaddinginto account.read-only, inherited - startOffset → double
-
read-only, inherited
Operators
-
operator ==(
other) → bool -
The equality operator.
inherited
Methods
-
createElement(
) → _VirtualListViewportElement -
RenderObjectWidgets always inflate to a
RenderObjectElementsubclass.inherited -
createRenderObject(
BuildContext context) → RenderList -
Creates an instance of the
RenderObjectclass that thisRenderObjectWidgetrepresents, using the configuration described by thisRenderObjectWidget.inherited -
debugFillDescription(
List<String> description) → void -
Add additional information to the given description for use by toString.
inherited -
didUnmountRenderObject(
RenderObject renderObject) → void -
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
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 -
updateRenderObject(
BuildContext context, RenderObject renderObject) → void -
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
inherited