您可以创建一个简单的可重复使用的分隔器。

创建分频器:

public class DividerItemDecorator extends RecyclerView.ItemDecoration {
    private Drawable mDivider;

    public DividerItemDecorator(Drawable divider) {
        mDivider = divider;
    }

    @Override
    public void onDraw(Canvas canvas, RecyclerView parent, RecyclerView.State state) {
        int dividerLeft = parent.getPaddingLeft();
        int dividerRight = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int dividerTop = child.getBottom() + params.bottomMargin;
            int dividerBottom = dividerTop + mDivider.getIntrinsicHeight();

            mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom);
            mDivider.draw(canvas);
        }
    }
}

创建分隔线:separator .xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <size
        android:width="1dp"
        android:height="1dp" />
    <solid android:color="@color/grey_300" />
</shape>

为你的Recyclerview添加分隔符:

RecyclerView.ItemDecoration dividerItemDecoration = new DividerItemDecorator(ContextCompat.getDrawable(context, R.drawable.divider));
recyclerView.addItemDecoration(dividerItemDecoration);

删除最后一项的分隔符:

为了防止最后一项画分隔线，你必须改变这条线。

for (int i = 0; i < childCount; i++) 

To

for (int i = 0; i < childCount-1; i++)

你的最终实现应该是这样的:

public class DividerItemDecorator extends RecyclerView.ItemDecoration {
    private Drawable mDivider;

    public DividerItemDecorator(Drawable divider) {
        mDivider = divider;
    }

    @Override
    public void onDraw(Canvas canvas, RecyclerView parent, RecyclerView.State state) {
        int dividerLeft = parent.getPaddingLeft();
        int dividerRight = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount - 1; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int dividerTop = child.getBottom() + params.bottomMargin;
            int dividerBottom = dividerTop + mDivider.getIntrinsicHeight();

            mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom);
            mDivider.draw(canvas);
        }
    }
}

希望能有所帮助。

你需要添加下一行…

mRecyclerView.addItemDecoration(new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL));

在res/drawable文件夹中创建一个单独的xml文件

 <?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <size android:height="1dp" />
    <solid android:color="@android:color/black" />
</shape>

在主活动中连接那个xml文件(your_file)，像这样:

DividerItemDecoration divider = new DividerItemDecoration(
    recyclerView.getContext(),
    DividerItemDecoration.VERTICAL
);
divider.setDrawable(ContextCompat.getDrawable(getBaseContext(), R.drawable.your_file));
recyclerView.addItemDecoration(divider);

不幸的是，Android只是把小事情变得太复杂了。实现你想要的最简单的方法，没有实现这里的DividerItemDecoration:

为RecyclerView添加你想要的分割线颜色的背景色:

<RecyclerView
    android:id="@+id/rvList"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:divider="@color/colorLightGray"
    android:scrollbars="vertical"
    tools:listitem="@layout/list_item"
    android:background="@android:color/darker_gray"/>

添加底部边距(android:layout_marginBottom)到项目的布局根(list_item.xml):

<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:layout_marginBottom="1dp">

    <TextView
        android:id="@+id/tvName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="John Doe" />

    <TextView
        android:id="@+id/tvDescription"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/tvName"
        android:text="Some description blah blah" />

</RelativeLayout>

这将在项目和RecyclerView的背景色之间提供1dp的空间(它是深灰色，将作为分隔符出现)。

Material-IO库中的MaterialDividerItemDecoration是许多用例的完整解决方案，如列表项划分或节划分。它拥有开发人员可能需要的一切，如插图和样式，而无需实现自己的项目装饰。这个材质分割线指南+实现真的很好检查。

Bhuvanesh BS解决方案有效。Kotlin版本:

import android.graphics.Canvas
import android.graphics.drawable.Drawable
import androidx.recyclerview.widget.RecyclerView

class DividerItemDecorator(private val mDivider: Drawable?) : RecyclerView.ItemDecoration() {

    override fun onDraw(
        canvas: Canvas,
        parent: RecyclerView,
        state: RecyclerView.State
    ) {

        val dividerLeft = parent.paddingLeft
        val dividerRight = parent.width - parent.paddingRight
        for (i in 0 until parent.childCount - 1) {
            val child = parent.getChildAt(i)
            val dividerTop =
                child.bottom + (child.layoutParams as RecyclerView.LayoutParams).bottomMargin
            val dividerBottom = dividerTop + mDivider!!.intrinsicHeight
            mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom)
            mDivider.draw(canvas)
        }
    }
}