ShapeWorkflow
interface ShapeWorkflow<ShapeSpecT : Any, InProgressShapeT : InProgressShape<ShapeSpecT, CompletedShapeT>, CompletedShapeT : Any>
An interface that can be implemented to provide custom inking functionality which replaces or augments the standard Jetpack Ink behavior. Providing an implementation of this is an advanced feature that isn't recommended for most apps - most use cases should prefer to use androidx.ink.brush.StockBrushes, or perhaps create a custom brush with androidx.ink.storage.BrushFamilySerialization.decode. But if those don't satisfy the need for fully custom programmatic geometry of stroke-like objects based on pointer input data, this interface can be implemented to control that, but in a way that can still take advantage of Ink's low latency drawing capabilities without needing to implement that from scratch.
The primary purpose of this object is to manage the recycling lifecycle of InProgressShape instances. A new instance will only be requested via create when the internal recycling logic determines it's necessary, and most of the time it will reuse existing recycled instances via InProgressShape.start.
| Parameters | |
|---|---|
<ShapeSpecT : Any> |
A styling specification type, typically pure declarative data, that indicates how pointer inputs are turned into geometry and rendered pixels. A standard, pure Ink implementation would use |
<InProgressShapeT : InProgressShape<ShapeSpecT, CompletedShapeT>> |
A specific type of |
<CompletedShapeT : Any> |
A type that represents the end result of an |
Summary
Public functions |
|
|---|---|
InProgressShapeT |
@WorkerThreadCalled when a new |
Int |
@WorkerThreadReturn the shape type of an item being drawn with the given |
Public properties |
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|---|---|
CompletedShapeRenderer<CompletedShapeT> |
An object that is called to render a |
InProgressShapeRenderer<InProgressShapeT> |
An object that is called to render an |
Public functions
create
@WorkerThread
fun create(shapeType: Int): InProgressShapeT
Called when a new InProgressShape is needed for the given shapeType to represent a shape.
The new InProgressShape will be used to represent a particular in-progress drawn object using InProgressShape.start. Since this object will be reused more than once, it is a good idea to do more expensive initialization once in this function at creation time to avoid unnecessary work in InProgressShape.start and the functions that are called at a high frequency in InProgressShape like InProgressShape.enqueueInputs and InProgressShape.update.
getShapeType
@WorkerThread
fun getShapeType(shapeSpec: ShapeSpecT): Int
Return the shape type of an item being drawn with the given ShapeSpecT for the purposes of recycling the InProgressShapeT instances. The simplest implementation of this can use a single shape type, but multiple shape types are supported. The returned integer value serves as a unique identifier - there are no limits on its value, and the numeric value of one type compared to another is meaningless beyond the fact that they are distinct.
Public properties
completedShapeRenderer
val completedShapeRenderer: CompletedShapeRenderer<CompletedShapeT>
An object that is called to render a CompletedShapeT instance to an android.graphics.Canvas. A standard, pure Ink implementation would be based on androidx.ink.rendering.android.canvas.CanvasStrokeRenderer.
inProgressShapeRenderer
val inProgressShapeRenderer: InProgressShapeRenderer<InProgressShapeT>
An object that is called to render an InProgressShapeT instance to an android.graphics.Canvas. A standard, pure Ink implementation would be based on androidx.ink.rendering.android.canvas.CanvasStrokeRenderer.