万能RecyclerView分割线

就不多叙述了，直接上代码

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.TypedValue;
import android.view.View;

public class DividerItemDecoration extends RecyclerView.ItemDecoration {

/*
 * RecyclerView的布局方向，默认先赋值
 * 为纵向布局
 * RecyclerView 布局可横向，也可纵向
 * 横向和纵向对应的分割想画法不一样
 * */
 private int mOrientation = LinearLayoutManager.VERTICAL;

/**
  * item之间分割线的size，1---5
  */
 private int mSize;

/**
  * 绘制item分割线的画笔，和设置其属性
  * 来绘制个性分割线
  */
 private Paint mPaint;

/**
  * 构造方法传入布局方向，不可不传
  *
  * @param context   context
  * @param orientation 布局方向
  * @param color    颜色
  * @param mItemSize  item之间分割线的size
  */

public DividerItemDecoration(Context context, int orientation, int color, int mItemSize) {
   this.mOrientation = orientation;
   /*
  item之间分割线的颜色
  */
   this.mSize= mItemSize;
   if (orientation != LinearLayoutManager.VERTICAL && orientation != LinearLayoutManager.HORIZONTAL) {
     throw new IllegalArgumentException("LinearLayoutManager error");
   }
   mSize = (int) TypedValue.applyDimension(mItemSize, TypedValue.COMPLEX_UNIT_DIP, context.getResources().getDisplayMetrics());
   mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
   mPaint.setColor(color);
    /*设置填充*/
   mPaint.setStyle(Paint.Style.FILL);
 }

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

/**
  * 绘制纵向 item 分割线
  *
  * @param canvas canvas
  * @param parent parent
  */
 private void drawVertical(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 + mSize;
     canvas.drawRect(left, top, right, bottom, mPaint);
   }
 }

/**
  * 绘制横向 item 分割线
  *
  * @param canvas canvas
  * @param parent parent
  */
 private void drawHorizontal(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 + mSize;
     canvas.drawRect(left, top, right, bottom, mPaint);
   }
 }

/**
  * 设置item分割线的size
  *
  * @param outRect outRect
  * @param view  view
  * @param parent parent
  * @param state  state
  */
 @Override
 public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
   if (mOrientation == LinearLayoutManager.VERTICAL) {
     outRect.set(0, 0, 0, mSize);
   } else {
     outRect.set(0, 0, mSize, 0);
   }
 }
}

调用的时候这样写：

mRecyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL, Color.RED,5));