A virtual viewport that displays a single child at a time.
Useful for Pageable widgets.
One unit of start offset corresponds to one child widget, which means a start offset of 2.75 indicates that the viewport is three quarters of the way between the child with index 2 and the child with index 3.
LazyPageViewport differs from PageViewport in that LazyPageViewport uses an ItemListBuilder to lazily create children. That makes LazyPageViewport suitable for an extremely large or infinite list of children but also makes it more verbose than PageViewport.
- Mixes-in
- VirtualViewportFromBuilder
Constructors
- LazyPageViewport({double startOffset: 0.0, Axis mainAxis: Axis.vertical, ViewportAnchor anchor: ViewportAnchor.start, int itemCount, ItemListBuilder itemBuilder })
-
Creates a virtual viewport that displays a single child at a time.
Properties
- itemBuilder → ItemListBuilder
-
read-only
- itemCount → int
-
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 - 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 - runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited - startOffset → double
-
read-only, inherited
Operators
-
operator ==(
other) → bool -
The equality operator.
inherited
Methods
-
createElement(
) → _VirtualPageViewportElement -
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