删除回收器视图中最后一行空列中的额外项目装饰

Question

我正在尝试删除空列项目装饰，如下图所示。我最初想在注释中使用下面的代码根据内容限制最后一行的跨距计数，但我没有成功。

以下是代码和图像的结果。

 val taskDatesView: RecyclerView = binding.taskDatesRecyclerView
    val manager = GridLayoutManager(context,10)
    taskDatesView.layoutManager = manager
    taskDatesView.adapter = taskDatesAdapter

    createTasksViewModel.taskDates.observe(viewLifecycleOwner) {
        it?.let(taskDatesAdapter::setTaskDates)
        val decoration = DividerItemDecoration(context, HORIZONTAL)
        taskDatesView.addItemDecoration(decoration)
        /*manager.spanSizeLookup = object :SpanSizeLookup(){
            override fun getSpanSize(position: Int): Int {
                val lastRowCount = (taskDatesAdapter.itemCount%10)
                if(position>taskDatesAdapter.itemCount -lastRowCount){
                    return lastRowCount
                }
                return 10
            }
        }*/
        

当我取消注释代码并运行应用程序时，结果如下：

任何代码参考或链接都会有所帮助。提前感谢。

Answer 1

在Custom Divider中，根据lastRowCount修改底部填充，它按预期工作。

下面是工作代码，结果还在代码中添加了注释，以便更好地理解

fun drawHorizontal(c: Canvas?, parent: RecyclerView) {
    val noOfColumns = 10
    val top = parent.paddingTop
    var bottom = parent.height - parent.paddingBottom
    val childCount = parent.childCount
    // values required not to draw the bottom for last empty columns
    val lastRowCount = childCount % noOfColumns
    val numOfRows = childCount / noOfColumns
    for (i in 0 until childCount) {
        val child = parent.getChildAt(i)
        val params = child.layoutParams as RecyclerView.LayoutParams
        // this can be optimized to calculate only once for every row
        val rowNumber = ((i + 1) / noOfColumns) + 1
        // Within every row after crossing the lastRowCount the bottom should not be extended
        if ((i * rowNumber) - (lastRowCount - 1) > 0) {
            bottom = (child.height * (numOfRows))
        }
        val left = child.right + params.rightMargin + mDivider.intrinsicHeight
        val right = left + mDivider.intrinsicWidth
        mDivider.setBounds(left, top, right, bottom)
        mDivider.draw(c!!)
    }
}

如果我们需要垂直和水平方向，使用上面和下面的代码

fun drawVertical(c: Canvas?, parent: RecyclerView){
    val dividerLeft = parent.paddingLeft
    val dividerRight = parent.width - parent.paddingRight
    val childCount = parent.childCount
    for (i in 0..childCount - 2) {
        val child: View = parent.getChildAt(i)
        val params = child.layoutParams as RecyclerView.LayoutParams
        val dividerTop: Int = child.getBottom() + params.bottomMargin
        val dividerBottom = dividerTop + mDivider.intrinsicHeight
        mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom)
        mDivider.draw(c)
    }
}