我有一个非常简单的方法在RecyclerView中添加一个分隔符。使用自定义适配器修改回收器视图布局，然后与回收器视图项目一起添加带有背景色(将是分隔色)的线性布局，并添加1dp的高度(或根据您的要求)和宽度以匹配父级。

下面是一个示例代码。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical" android:layout_width="match_parent"
              android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:padding="18dp">

        <TextView
            android:id="@+id/list_row_SNO"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight=".8"
            android:layout_gravity="end"
            android:text="44."
            android:textAlignment="center"
            android:textSize="24sp"
            android:textColor="@color/colorBlack"
            android:fontFamily="sans-serif-condensed" />

        <TextView
            android:id="@+id/list_row_Heading"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight=".2"
            android:layout_gravity="start"
            android:text="Student's application for leave and this what"
            android:textAlignment="textStart"
            android:textSize="24sp"
            android:textColor="@color/colorBlack"
            android:fontFamily="sans-serif-condensed" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/colorHighlight">
    </LinearLayout>

</LinearLayout>

您可以通过编程方式轻松地添加它。

如果你的布局管理器是线性布局，那么你可以使用:

DividerItemDecoration是一个RecyclerView。ItemDecoration即可以 用作LinearLayoutManager项之间的分隔符。它支持 水平方向和垂直方向。

mDividerItemDecoration =
  new DividerItemDecoration(recyclerView.getContext(),
                            mLayoutManager.getOrientation());
recyclerView.addItemDecoration(mDividerItemDecoration);

源

对于GridLayoutManager，我使用这个:

public class GridSpacesItemDecoration : RecyclerView.ItemDecoration
{
    private int space;

    public GridSpacesItemDecoration(int space) {
        this.space = space;
    }

    public override void GetItemOffsets(Android.Graphics.Rect outRect, View view, RecyclerView parent, RecyclerView.State state)
    {
        var position = parent.GetChildLayoutPosition(view);

        /// Only for GridLayoutManager Layouts
        var manager = parent.GetLayoutManager() as GridLayoutManager;

        if (parent.GetChildLayoutPosition(view) < manager.SpanCount)
            outRect.Top = space;

        if (position % 2 != 0) {
            outRect.Right = space;
        }

        outRect.Left = space;
        outRect.Bottom = space;
    }
}

这适用于任何跨度。

RecyclerView和ListView有点不同。实际上，RecyclerView需要一个类似ListView的结构。例如，线性布局。LinearLayout有用于划分每个元素的参数。

在下面的代码中，我有一个RecyclerView由一个线性布局中的CardView对象组成，其中有一个“填充”，将在项目之间放置一些空间。把空间缩小，就能得到一条线。

下面是recyclerview_layout.xml文件中的Recycler视图:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".ToDoList">

    <!-- A RecyclerView with some commonly used attributes -->
    <android.support.v7.widget.RecyclerView
        android:id="@+id/todo_recycler_view"
        android:scrollbars="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>

这里是每个项目看起来像(它显示为分割由于android:填充在线性布局包围一切)在另一个文件:cards_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent"

    **android:padding="@dimen/activity_vertical_margin"**>

    <!-- A CardView that contains a TextView -->
    <android.support.v7.widget.CardView
        xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:id="@+id/card_view"
        android:layout_gravity="center"
        android:layout_width="match_parent"
        android:layout_height="100dp"
        android:elevation="30dp"
        card_view:cardElevation="3dp">
        <TextView
            android:id="@+id/info_text"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
        />
    </android.support.v7.widget.CardView>
</LinearLayout>

使用这个类在你的RecyclerView中设置分隔符。

public class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {

    private int spanCount;
    private int spacing;
    private boolean includeEdge;

    public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
        this.spanCount = spanCount;
        this.spacing = spacing;
        this.includeEdge = includeEdge;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        int position = parent.getChildAdapterPosition(view); // Item position
        int column = position % spanCount; // Item column

        if (includeEdge) {
            outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
            outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)

            if (position < spanCount) { // Top edge
                outRect.top = spacing;
            }
            outRect.bottom = spacing; // Item bottom
        } else {
            outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
            outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f / spanCount) * spacing)
            if (position >= spanCount) {
                outRect.top = spacing; // Item top
            }
        }
    }
}

最新的方法是这样的，例如在Fragment的onCreateView中使用:

        val recyclerView = rootView.findViewById<RecyclerView>(R.id.recycler_view)
        recyclerView.adapter = mListAdapter
        recyclerView.layoutManager = LinearLayoutManager(context)
        rootView.context.let {
            val dividerItemDecoration = MaterialDividerItemDecoration(
                it,
                MaterialDividerItemDecoration.VERTICAL
            )
            dividerItemDecoration.isLastItemDecorated = false

            // https://github.com/material-components/material-components-android/blob/master/docs/components/Divider.md
            // Needed if you did not set colorOnSurface in your theme because otherwise the default color would be pink_900 -> default according to Material should be colorOnSurface (12% opacity applied automatically on top).
//            dividerItemDecoration.setDividerColorResource(it, R.color.colorDivider)

            recyclerView.addItemDecoration(dividerItemDecoration)
        }

我想你们可以忘记之前所有的解。