你可以用很多方法去做。
您可以使用带有verticalArrangement = Arrangement.SpaceBetween的列，将weight(1f,false)分配给最后一行：

Column(
     Modifier.fillMaxHeight(),
     verticalArrangement = Arrangement.SpaceBetween) {
     
     //All elements 
     Column {

        // RED BOX
        
        //...
        Spacer(
            modifier = Modifier
                .fillMaxWidth()
                .background(Green)
                .height(15.dp)
        )

       //... Green box
    }

    //LAST ROW
    Row(
        modifier = Modifier
            .weight(1f, false)
    ) {
        //...
    }
 }

您可以在GreenBox和Blue Box之间使用Spacer(modifier.weight(1f))来创建它们之间的空间，或者您可以使用Layout函数创建自定义列，并将最后一个Placeable的y位置设置为Composable的高度-最后一个Composble的高度

Column(modifier = Modifier
        .fillMaxHeight()
        .background(Color.LightGray)) {
        Text(
            "First Text",
            modifier = Modifier
                .background(Color(0xffF44336)),
            color = Color.White
        )
        Text(
            "Second Text",
            modifier = Modifier
                .background(Color(0xff9C27B0)),
            color = Color.White
        )
        Spacer(modifier = Modifier.weight(1f))
        Text(
            "Third Text",
            modifier = Modifier
                .background(Color(0xff2196F3)),
            color = Color.White
        )
    }

结果：

自定义布局

@Composable
private fun CustomColumn(
    modifier: Modifier,
    content: @Composable () -> Unit
) {
    Layout(
        modifier = modifier,
        content = content
    ) { measurables, constraints ->

        val looseConstraints = constraints.copy(
            minWidth = 0,
            maxWidth = constraints.maxWidth,
            minHeight = 0,
            maxHeight = constraints.maxHeight
        )

        // Don't constrain child views further, measure them with given constraints
        // List of measured children
        val placeables = measurables.map { measurable ->
            // Measure each child
            measurable.measure(looseConstraints)
        }

        // Track the y co-ord we have placed children up to
        var yPosition = 0

        // Set the size of the layout as big as it can
        layout(constraints.maxWidth, constraints.maxHeight) {
            // Place children in the parent layout
            placeables.forEachIndexed { index, placeable ->

                println("Placeable width: ${placeable.width}, measuredWidth: ${placeable.measuredWidth}")
                // Position item on the screen
                if (index == placeables.size - 1) {
                    placeable.placeRelative(x = 0, y = constraints.maxHeight - placeable.height)
                } else {
                    placeable.placeRelative(x = 0, y = yPosition)
                }

                // Record the y co-ord placed up to
                yPosition += placeable.height
            }
        }
    }
}

用途

CustomColumn(
        modifier = Modifier
            .fillMaxHeight()
            .background(Color.LightGray)
    ) {
        Text(
            "First Text",
            modifier = Modifier
                .background(Color(0xffF44336)),
            color = Color.White
        )
        Text(
            "Second Text",
            modifier = Modifier
                .background(Color(0xff9C27B0)),
            color = Color.White
        )
        Spacer(modifier = Modifier.weight(1f))
        Text(
            "Third Text",
            modifier = Modifier
                .background(Color(0xff2196F3)),
            color = Color.White
        )
    }

结果：

在这个布局示例中，您应该考虑如何使用约束测量可测量项以及总宽度和总高度。这需要一点实践，但您可以获得更多独特的设计，而且工作量更少（更优化）的可组合比现成的。这里我设置为最大宽度布局，所以无论你分配的宽度是整个宽度。它's为了演示，您可以根据需要在layout中设置最大宽度或高度。