A delegate that supplies children for slivers.
Many slivers lazily construct their box children to avoid creating more children than are visible through the Viewport. Rather than receiving their children as an explicit List, they receive their children using a SliverChildDelegate.
It's uncommon to subclass SliverChildDelegate. Instead, consider using one of the existing subclasses that provide adaptors to builder callbacks or explicit child lists.
Abstract const constructor. This constructor enables subclasses to provide
const constructors so that they can be used in const expressions.
BuildContext context, int index) → Widget
- Returns the child with the given index. [...]
List< String>description) → void
Add additional information to the given description for use by toString.
int firstIndex, int lastIndex) → void
- Called at the end of layout to indicate that layout is now complete. [...]
int firstIndex, int lastIndex, double leadingScrollOffset, double trailingScrollOffset) → double
- Returns an estimate of the max scroll extent for all the children. [...]
SliverChildDelegate oldDelegate) → bool
- Called whenever a new instance of the child delegate class is provided to the sliver. [...]
) → String
- Returns a string representation of this object.
Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]