animatable.kt

val animatable = remember { Animatable(0f) }
...
//Modifier.tapOrPress
    onCompleted = {
      scope.launch {
      selectedPosition = it
      animatable.snapTo(1f)
      }
    }
...
// @Composable Canvas
    drawRoundRect(
      brush = brush,
      topLeft = Offset(
        x = horizontalPadding + distance.times(selectedBar!!.index) - selectionWidth.div(2),
        y = chartAreaHeight - chartAreaHeight.times(animatable.value)), // use of animatable value
        size = Size(selectionWidth, chartAreaHeight),
        cornerRadius = CornerRadius(cornerRadius)
    )