这个链接对我来说很有吸引力:

https://gist.github.com/lapastillaroja/858caf1a82791b6c1a36

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.view.View;

public class DividerItemDecoration extends RecyclerView.ItemDecoration {

    private Drawable mDivider;
    private boolean mShowFirstDivider = false;
    private boolean mShowLastDivider = false;


    public DividerItemDecoration(Context context, AttributeSet attrs) {
        final TypedArray a = context
                .obtainStyledAttributes(attrs, new int[]{android.R.attr.listDivider});
        mDivider = a.getDrawable(0);
        a.recycle();
    }

    public DividerItemDecoration(Context context, AttributeSet attrs, boolean showFirstDivider,
            boolean showLastDivider) {
        this(context, attrs);
        mShowFirstDivider = showFirstDivider;
        mShowLastDivider = showLastDivider;
    }

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

    public DividerItemDecoration(Drawable divider, boolean showFirstDivider,
            boolean showLastDivider) {
        this(divider);
        mShowFirstDivider = showFirstDivider;
        mShowLastDivider = showLastDivider;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
            RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        if (mDivider == null) {
            return;
        }
        if (parent.getChildPosition(view) < 1) {
            return;
        }

        if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
            outRect.top = mDivider.getIntrinsicHeight();
        } else {
            outRect.left = mDivider.getIntrinsicWidth();
        }
    }

    @Override
    public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
        if (mDivider == null) {
            super.onDrawOver(c, parent, state);
            return;
        }

        // Initialization needed to avoid compiler warning
        int left = 0, right = 0, top = 0, bottom = 0, size;
        int orientation = getOrientation(parent);
        int childCount = parent.getChildCount();

        if (orientation == LinearLayoutManager.VERTICAL) {
            size = mDivider.getIntrinsicHeight();
            left = parent.getPaddingLeft();
            right = parent.getWidth() - parent.getPaddingRight();
        } else { //horizontal
            size = mDivider.getIntrinsicWidth();
            top = parent.getPaddingTop();
            bottom = parent.getHeight() - parent.getPaddingBottom();
        }

        for (int i = mShowFirstDivider ? 0 : 1; i < childCount; i++) {
            View child = parent.getChildAt(i);
            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            if (orientation == LinearLayoutManager.VERTICAL) {
                top = child.getTop() - params.topMargin;
                bottom = top + size;
            } else { //horizontal
                left = child.getLeft() - params.leftMargin;
                right = left + size;
            }
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }

        // show last divider
        if (mShowLastDivider && childCount > 0) {
            View child = parent.getChildAt(childCount - 1);
            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            if (orientation == LinearLayoutManager.VERTICAL) {
                top = child.getBottom() + params.bottomMargin;
                bottom = top + size;
            } else { // horizontal
                left = child.getRight() + params.rightMargin;
                right = left + size;
            }
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    private int getOrientation(RecyclerView parent) {
        if (parent.getLayoutManager() instanceof LinearLayoutManager) {
            LinearLayoutManager layoutManager = (LinearLayoutManager) parent.getLayoutManager();
            return layoutManager.getOrientation();
        } else {
            throw new IllegalStateException(
                    "DividerItemDecoration can only be used with a LinearLayoutManager.");
        }
    }
}

然后在你的活动中:

mCategoryRecyclerView.addItemDecoration(
    new DividerItemDecoration(this, null));

或者如果你使用片段:

mCategoryRecyclerView.addItemDecoration(
    new DividerItemDecoration(getActivity(), null));

这是我在Kotlin中为列显示(网格)所做的

  class ItemDecorationColumns(private val space: Int) : ItemDecoration() {

    override fun getItemOffsets(
        outRect: Rect,
        view: View,
        parent: RecyclerView,
        state: RecyclerView.State
    ) {
        val position = parent.getChildLayoutPosition(view)
        val manager = parent.layoutManager as GridLayoutManager?
        val spanCount = manager?.spanCount ?: 0

        if (position < spanCount) {
            outRect.top = space
        }

        if (position % 2 != 0) {
            outRect.right = space
        }
        outRect.left = space
        outRect.bottom = space
    }
}

使用

rvAlbums.addItemDecoration(ItemDecorationColumns(resources.getDimensionPixelSize(R.dimen.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。

public class VerticalItemDecoration extends RecyclerView.ItemDecoration {

    private boolean verticalOrientation = true;
    private int space = 10;

    public VerticalItemDecoration(int value, boolean verticalOrientation) {
        this.space = value;
        this.verticalOrientation = verticalOrientation;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
                               RecyclerView.State state) {
        // Skip first item in the list
        if (parent.getChildAdapterPosition(view) != 0) {
            if (verticalOrientation) {
                outRect.set(space, 0, 0, 0);
            } else if (!verticalOrientation) {
                outRect.set(0, space, 0, 0);
            }
        }
    }
}

mCompletedShippingRecyclerView.addItemDecoration(new VerticalItemDecoration(20,false));

如果有人只想在项目之间添加10dp的间距，你可以通过设置一个drawable到DividerItemDecoration来实现:

DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(
    recyclerView.getContext(),
    layoutManager.getOrientation()
);

dividerItemDecoration.setDrawable(
    ContextCompat.getDrawable(getContext(), R.drawable.divider_10dp)
);

recyclerView.addItemDecoration(dividerItemDecoration);

其中，divider_10dpis一个可绘制资源，包含:

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <size android:height="10dp"/>
    <solid android:color="@android:color/transparent"/>
</shape>

以下是我的偷懒方法，但它很有效: 将CardView包装在一个布局中，并在父布局上设置一个填充/边距来模拟分隔符，并强制将普通分隔符设置为null。

文件list_item.xml

<LinearLayout
    android:id="@+id/entry_item_layout_container"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:paddingBottom="<divider_size>" > // This is the divider
    <CardView
        android:layout_width="<width_size>"
        android:layout_height="<height_size>">
        ...
    </CardView>
</LinearLayout

文件list.xml

<RecyclerView
    android:divider="@null"
    android:layout_width="<width_size>"
    android:layout_height="<height_size>"
    ...
/>