只需在回收器视图对象的init之后添加这一行。

在片段:

mRecyclerView.addItemDecoration(new DividerItemDecoration(getActivity(),android.R.drawable.divider_horizontal_bright));

在活动

mRecyclerView.addItemDecoration(new DividerItemDecoration(this,android.R.drawable.divider_horizontal_bright));

项目装饰

public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    public static final int VERTICAL_LIST = 0;

    public DividerItemDecoration(ListActivity listActivity, Object p1) {
    }

    private static final int[] ATTRS = new int[]{android.R.attr.listDivider};

    private Drawable mDivider;

    /**
     * Default divider will be used
     */
    public DividerItemDecoration(Context context) {
        final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
        mDivider = styledAttributes.getDrawable(0);
        styledAttributes.recycle();
    }

    /**
     * Custom divider will be used
     */
    public DividerItemDecoration(Context context, int resId) {
        mDivider = ContextCompat.getDrawable(context, resId);
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        int left = parent.getPaddingLeft();
        int right = 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 top = child.getBottom() + params.bottomMargin;
            int bottom = top + mDivider.getIntrinsicHeight();

            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }
}

一个简单的ItemDecoration实现，所有项目之间的空间相等:

public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
    private int space;

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

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        outRect.left = space;
        outRect.right = space;
        outRect.bottom = space;

        // Add top margin only for the first item to avoid double space between items
        if(parent.getChildAdapterPosition(view) == 0) {
            outRect.top = space;
        }
    }
}

Here is a simple hack to add a divider Just add a background to the layout of your recycler item as follows <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="@drawable/shape_border" android:gravity="center" android:orientation="horizontal" android:padding="5dp"> <ImageView android:id="@+id/imageViewContactLogo" android:layout_width="60dp" android:layout_height="60dp" android:layout_marginRight="10dp" android:src="@drawable/ic_user" /> <LinearLayout android:id="@+id/linearLayout" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="0.92" android:gravity="center|start" android:orientation="vertical"> <TextView android:id="@+id/textViewContactName" android:layout_width="wrap_content" android:layout_height="wrap_content" android:singleLine="true" android:text="Large Text" android:textAppearance="?android:attr/textAppearanceLarge" /> <TextView android:id="@+id/textViewStatusOrNumber" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="5dp" android:singleLine="true" android:text="" android:textAppearance="?android:attr/textAppearanceMedium" /> </LinearLayout> <TextView android:id="@+id/textViewUnreadCount" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginRight="10dp" android:padding="5dp" android:text="" android:textAppearance="?android:attr/textAppearanceMedium" android:textColor="@color/red" android:textSize="22sp" /> <Button android:id="@+id/buttonInvite" android:layout_width="54dp" android:layout_height="wrap_content" android:background="@drawable/ic_add_friend" /> </LinearLayout>

在drawable文件夹中创建以下shape_border.xml文件:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle" >
    <gradient
         android:angle="270"
         android:centerColor="@android:color/transparent"
         android:centerX="0.01"
         android:startColor="#000" />
</shape>

这是最终的结果-一个带分隔符的RecyclerView。

因为我已经设置了ItemAnimators。ItemDecorator不会随着动画一起进入或退出。

我只是在我的项目视图布局文件中为每个项目设置了一个视图行。它解决了我的案子。对于一个简单的分割器来说，我觉得它的魔法太多了。

<View
    android:layout_width="match_parent"
    android:layout_height="1px"
    android:layout_marginLeft="5dp"
    android:layout_marginRight="5dp"
    android:background="@color/lt_gray"/>

其中一种方法是同时使用cardview和recycler视图。我们可以很容易地添加一个效果，比如分隔线。 示例:使用RecyclerView创建动态列表 另一种方法是将视图作为分隔符添加到回收器视图的list_item_layout中。 <视图 android: id =“@ + id / view1” android: layout_width = " match_parent " android: layout_height = " 1 dp " android:背景= " @color / colorAccent " / >

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。