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VelocityTrackerKt

public final class VelocityTrackerKt


Summary

Public methods

static final void

Track the positions and timestamps inside this event change.

Public methods

addPointerInputChange

public static final void addPointerInputChange(
    @NonNull VelocityTracker receiver,
    @NonNull PointerInputChange event
)

Track the positions and timestamps inside this event change.

For optimal tracking, this should be called for the DOWN event and all MOVE events, including any touch-slop-captured MOVE event.

Since Compose uses relative positions inside PointerInputChange, this should be taken into consideration when using this method. Right now, we use the first down to initialize an accumulator and use subsequent deltas to simulate an actual movement from relative positions in PointerInputChange. This is required because VelocityTracker requires data that can be fit into a curve, which might not happen with relative positions inside a moving target for instance.

Parameters
@NonNull PointerInputChange event

Pointer change to track.