WormHorizontalPagerIndicator.kt

@ExperimentalPagerApi
@Composable
fun WormHorizontalPagerIndicator(
    pagerState: PagerState,
    modifier: Modifier = Modifier,
    activeColor: Color = LocalContentColor.current.copy(alpha = LocalContentAlpha.current),
    inactiveColor: Color = activeColor.copy(ContentAlpha.disabled),
    indicatorWidth: Dp = 8.dp,
    activeIndicatorWidth: Dp = 25.dp,
    indicatorHeight: Dp = indicatorWidth,
    spacing: Dp = indicatorWidth,
    indicatorShape: Shape = CircleShape,
) {
    Box(
        modifier = modifier,
        contentAlignment = Alignment.CenterStart
    ) {
        Row(
            horizontalArrangement = Arrangement.spacedBy(spacing),
            verticalAlignment = Alignment.CenterVertically,
        ) {
            repeat(pagerState.pageCount) { index ->
                val currentPageOffset = pagerState.currentPageOffset
                val isCurrentPage = index == pagerState.currentPage
                val isNextPage = index == pagerState.targetPage

                val width: Dp = when {
                    isCurrentPage -> {
                        (activeIndicatorWidth * (1 - abs(currentPageOffset))).coerceIn(
                            indicatorWidth,
                            activeIndicatorWidth
                        )
                    }
                    isNextPage -> {
                        (activeIndicatorWidth * abs(currentPageOffset)).coerceIn(
                            indicatorWidth,
                            activeIndicatorWidth
                        )
                    }
                    else -> {
                        indicatorWidth
                    }
                }
                val color: Color = when {
                    isCurrentPage -> {
                        lerp(
                            activeColor,
                            inactiveColor,
                            abs(currentPageOffset).coerceIn(0f, 1f)
                        )
                    }
                    isNextPage -> {
                        lerp(
                            inactiveColor,
                            activeColor,
                            abs(currentPageOffset).coerceIn(0f, 1f)
                        )
                    }
                    else -> {
                        inactiveColor
                    }
                }

                Box(
                    Modifier
                        .size(
                            width = width,
                            height = indicatorHeight
                        )
                        .background(
                            color = color,
                            shape = indicatorShape
                        )
                )
            }
        }
    }
}