RecyclerView的萬能分割線

效果圖：

使用方法：

添加默認分割線：高度爲2px，顏色爲灰色

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

添加自定義分割線：可自定義分割線drawable

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

添加自定義分割線：可自定義分割線高度和顏色

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

萬能分割線登場：

  1 package utils;
  2 
  3 import android.content.Context;
  4 import android.content.res.TypedArray;
  5 import android.graphics.Canvas;
  6 import android.graphics.Paint;
  7 import android.graphics.Rect;
  8 import android.graphics.drawable.Drawable;
  9 import android.support.v4.content.ContextCompat;
 10 import android.support.v7.widget.LinearLayoutManager;
 11 import android.support.v7.widget.RecyclerView;
 12 import android.view.View;
 13 
 14 /**
 15  * Created by ${火龍裸先生} on 2016/10/29.
 16  * 郵箱：791335000@qq.com
 17  */
 18 public class RecyclerViewDivider extends RecyclerView.ItemDecoration {
 19     private Paint mPaint;
 20     private Drawable mDivider;
 21     private int mDividerHeight = 2;//分割線高度，默認爲1px
 22     private int mOrientation;//列表的方向：LinearLayoutManager.VERTICAL或LinearLayoutManager.HORIZONTAL
 23     private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
 24 
 25     /**
 26      * 默認分割線：高度爲2px，顏色爲灰色
 27      *
 28      * @param context
 29      * @param orientation 列表方向
 30      */
 31     public RecyclerViewDivider(Context context, int orientation) {
 32         if (orientation != LinearLayoutManager.VERTICAL && orientation != LinearLayoutManager.HORIZONTAL) {
 33             throw new IllegalArgumentException("請輸入正確的參數！");
 34         }
 35         mOrientation = orientation;
 36 
 37         final TypedArray a = context.obtainStyledAttributes(ATTRS);
 38         mDivider = a.getDrawable(0);
 39         a.recycle();
 40     }
 41 
 42     /**
 43      * 自定義分割線
 44      *
 45      * @param context
 46      * @param orientation 列表方向
 47      * @param drawableId  分割線圖片
 48      */
 49     public RecyclerViewDivider(Context context, int orientation, int drawableId) {
 50         this(context, orientation);
 51         mDivider = ContextCompat.getDrawable(context, drawableId);
 52         mDividerHeight = mDivider.getIntrinsicHeight();
 53     }
 54 
 55     /**
 56      * 自定義分割線
 57      *
 58      * @param context
 59      * @param orientation   列表方向
 60      * @param dividerHeight 分割線高度
 61      * @param dividerColor  分割線顏色
 62      */
 63     public RecyclerViewDivider(Context context, int orientation, int dividerHeight, int dividerColor) {
 64         this(context, orientation);
 65         mDividerHeight = dividerHeight;
 66         mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
 67         mPaint.setColor(dividerColor);
 68         mPaint.setStyle(Paint.Style.FILL);
 69     }
 70 
 71 
 72     //獲取分割線尺寸
 73     @Override
 74     public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
 75         super.getItemOffsets(outRect, view, parent, state);
 76         outRect.set(0, 0, 0, mDividerHeight);
 77     }
 78 
 79     //繪製分割線
 80     @Override
 81     public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
 82         super.onDraw(c, parent, state);
 83         if (mOrientation == LinearLayoutManager.VERTICAL) {
 84             drawVertical(c, parent);
 85         } else {
 86             drawHorizontal(c, parent);
 87         }
 88     }
 89 
 90     //繪製橫向 item 分割線
 91     private void drawHorizontal(Canvas canvas, RecyclerView parent) {
 92         final int left = parent.getPaddingLeft();
 93         final int right = parent.getMeasuredWidth() - parent.getPaddingRight();
 94         final int childSize = parent.getChildCount();
 95         for (int i = 0; i < childSize; i++) {
 96             final View child = parent.getChildAt(i);
 97             RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
 98             final int top = child.getBottom() + layoutParams.bottomMargin;
 99             final int bottom = top + mDividerHeight;
100             if (mDivider != null) {
101                 mDivider.setBounds(left, top, right, bottom);
102                 mDivider.draw(canvas);
103             }
104             if (mPaint != null) {
105                 canvas.drawRect(left, top, right, bottom, mPaint);
106             }
107         }
108     }
109 
110     //繪製縱向 item 分割線
111     private void drawVertical(Canvas canvas, RecyclerView parent) {
112         final int top = parent.getPaddingTop();
113         final int bottom = parent.getMeasuredHeight() - parent.getPaddingBottom();
114         final int childSize = parent.getChildCount();
115         for (int i = 0; i < childSize; i++) {
116             final View child = parent.getChildAt(i);
117             RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
118             final int left = child.getRight() + layoutParams.rightMargin;
119             final int right = left + mDividerHeight;
120             if (mDivider != null) {
121                 mDivider.setBounds(left, top, right, bottom);
122                 mDivider.draw(canvas);
123             }
124             if (mPaint != null) {
125                 canvas.drawRect(left, top, right, bottom, mPaint);
126             }
127         }
128     }
129 
130 }