Android自定义上下左右间隔线

/** * author: Y_Qing * date: 2018/5/7 */public class SpaceItemDecoration extends RecyclerView.ItemDecoration {  private int space;  Paint mPaint;  public SpaceItemDecoration(int space) {    this.space = space;    mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);    mPaint.setColor(0xffededed);    mPaint.setStyle(Paint.Style.FILL);  }  private static final int HORIZONTAL = 355;  @Override  public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {    int itemViewType = parent.getLayoutManager().getItemViewType(view);    if (itemViewType == HORIZONTAL) { //根据ViewType类型来判断是否展示线      outRect.bottom = space;      if (parent.getChildLayoutPosition(view) % 2 == 0) {        outRect.right = space / 2;        outRect.left = space;      } else {        outRect.right = space;        outRect.left = space / 2;      }    }  }  @Override  public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {    c.save();    if (parent.getLayoutManager() instanceof GridLayoutManager) {      if ((((GridLayoutManager) parent.getLayoutManager())).getSpanCount() == 2) {        draw(c, parent);      }    }    c.restore();  }  //绘制横向 item 分割线  private void draw(Canvas canvas, RecyclerView parent) {    int childSize = parent.getChildCount();    for (int i = 0; i < childSize; i++) {      View child = parent.getChildAt(i);      RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();      int left = child.getLeft();      int right = child.getRight();      int top = child.getBottom() + layoutParams.bottomMargin;      int bottom = top + space;      if (mPaint != null) {        canvas.drawRect(left, top, right, bottom, mPaint);//绘制图片下放的水平线      }      if (parent.getChildLayoutPosition(child) % 2 == 0) {        canvas.drawRect(0, child.getTop(), left, child.getBottom() + space, mPaint);//绘制左边图片的左间线      }      top = child.getTop();      bottom = child.getBottom() + space;      left = child.getRight() + layoutParams.rightMargin;      right = left + space;      if (mPaint != null) {        canvas.drawRect(left, top, right, bottom, mPaint);//绘制图片的右间线      }    }  }}

private void initSpaceLine() {    if (decor == null) {      decor = new SpaceItemDecoration(ViewUtil.dp2px(5));      recycleListView.addItemDecoration(decor);    }  }