RecyclerView的万能分割线

效果图：

使用方法：

添加默认分割线：高度为2px，颜色为灰色

 mRecyclerView.addItemDecoration(new RecyclerViewDivider(mContext, LinearLayoutManager.VERTICAL));

添加自定义分割线：可自定义分割线drawable

 mRecyclerView.addItemDecoration(new RecyclerViewDivider(
     mContext, LinearLayoutManager.VERTICAL, R.drawable.divider_mileage));

添加自定义分割线：可自定义分割线高度和颜色

 mRecyclerView.addItemDecoration(new RecyclerViewDivider(
     mContext, LinearLayoutManager.VERTICAL, 10, ContextCompat.getColor(mContext, R.color.divide_gray_color)));

万能分割线登场：

 package utils;

 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.support.v4.content.ContextCompat;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.view.View;

 /**
  * Created by ${火龙裸先生} on 2016/10/29.
  * 邮箱：791335000@qq.com
  */
 public class RecyclerViewDivider extends RecyclerView.ItemDecoration {
     private Paint mPaint;
     private Drawable mDivider;
     private int mDividerHeight = 2;//分割线高度，默认为1px
     private int mOrientation;//列表的方向：LinearLayoutManager.VERTICAL或LinearLayoutManager.HORIZONTAL
     private static final int[] ATTRS = new int[]{android.R.attr.listDivider};

     /**
      * 默认分割线：高度为2px，颜色为灰色
      *
      * @param context
      * @param orientation 列表方向
      */
     public RecyclerViewDivider(Context context, int orientation) {
         if (orientation != LinearLayoutManager.VERTICAL && orientation != LinearLayoutManager.HORIZONTAL) {
             throw new IllegalArgumentException("请输入正确的参数！");
         }
         mOrientation = orientation;

         final TypedArray a = context.obtainStyledAttributes(ATTRS);
         mDivider = a.getDrawable(0);
         a.recycle();
     }

     /**
      * 自定义分割线
      *
      * @param context
      * @param orientation 列表方向
      * @param drawableId  分割线图片
      */
     public RecyclerViewDivider(Context context, int orientation, int drawableId) {
         this(context, orientation);
         mDivider = ContextCompat.getDrawable(context, drawableId);
         mDividerHeight = mDivider.getIntrinsicHeight();
     }

     /**
      * 自定义分割线
      *
      * @param context
      * @param orientation   列表方向
      * @param dividerHeight 分割线高度
      * @param dividerColor  分割线颜色
      */
     public RecyclerViewDivider(Context context, int orientation, int dividerHeight, int dividerColor) {
         this(context, orientation);
         mDividerHeight = dividerHeight;
         mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         mPaint.setColor(dividerColor);
         mPaint.setStyle(Paint.Style.FILL);
     }

     //获取分割线尺寸
     @Override
     public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
         super.getItemOffsets(outRect, view, parent, state);
         outRect.set(0, 0, 0, mDividerHeight);
     }

     //绘制分割线
     @Override
     public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
         super.onDraw(c, parent, state);
         if (mOrientation == LinearLayoutManager.VERTICAL) {
             drawVertical(c, parent);
         } else {
             drawHorizontal(c, parent);
         }
     }

     //绘制横向 item 分割线
     private void drawHorizontal(Canvas canvas, RecyclerView parent) {
         final int left = parent.getPaddingLeft();
         final int right = parent.getMeasuredWidth() - parent.getPaddingRight();
         final int childSize = parent.getChildCount();
         for (int i = 0; i < childSize; i++) {
             final View child = parent.getChildAt(i);
             RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
             final int top = child.getBottom() + layoutParams.bottomMargin;
             final int bottom = top + mDividerHeight;
             if (mDivider != null) {
                 mDivider.setBounds(left, top, right, bottom);
                 mDivider.draw(canvas);
             }
             if (mPaint != null) {
                 canvas.drawRect(left, top, right, bottom, mPaint);
             }
         }
     }

     //绘制纵向 item 分割线
     private void drawVertical(Canvas canvas, RecyclerView parent) {
         final int top = parent.getPaddingTop();
         final int bottom = parent.getMeasuredHeight() - parent.getPaddingBottom();
         final int childSize = parent.getChildCount();
         for (int i = 0; i < childSize; i++) {
             final View child = parent.getChildAt(i);
             RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
             final int left = child.getRight() + layoutParams.rightMargin;
             final int right = left + mDividerHeight;
             if (mDivider != null) {
                 mDivider.setBounds(left, top, right, bottom);
                 mDivider.draw(canvas);
             }
             if (mPaint != null) {
                 canvas.drawRect(left, top, right, bottom, mPaint);
             }
         }
     }

 }