FlowDelegate class abstract
A delegate that controls the appearance of a flow layout.
Flow layouts are optimized for moving children around the screen using transformation matrices. For optimal performance, construct the FlowDelegate with an Animation that ticks whenever the delegate wishes to change the transformation matrices for the children and avoid rebuilding the Flow widget itself every animation frame.
See also:
Constructors
- FlowDelegate({Listenable? repaint})
-
The flow will repaint whenever
repaintnotifies its listeners.const
Properties
- hashCode → int
-
The hash code for this object.
no setterinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
getConstraintsForChild(
int i, BoxConstraints constraints) → BoxConstraints - Override to control the layout constraints given to each child.
-
getSize(
BoxConstraints constraints) → Size - Override to control the size of the container for the children.
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
paintChildren(
FlowPaintingContext context) → void - Override to paint the children of the flow.
-
shouldRelayout(
covariant FlowDelegate oldDelegate) → bool - Override this method to return true when the children need to be laid out. This should compare the fields of the current delegate and the given oldDelegate and return true if the fields are such that the layout would be different.
-
shouldRepaint(
covariant FlowDelegate oldDelegate) → bool - Override this method to return true when the children need to be repainted. This should compare the fields of the current delegate and the given oldDelegate and return true if the fields are such that paintChildren would act differently.
-
toString(
) → String -
Override this method to include additional information in the
debugging data printed by debugDumpRenderTree and friends.
override
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited