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androidx.compose.ui.input.pointer.util

Classes

VelocityTracker

Computes a pointer's velocity.

Cmn
VelocityTracker1D

A velocity tracker calculating velocity in 1 dimension.

Cmn

Extension functions summary

Unit

Track the positions and timestamps inside this event change.

Cmn

Extension functions

addPointerInputChange

fun VelocityTracker.addPointerInputChange(event: PointerInputChange): Unit

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
event: PointerInputChange

Pointer change to track.