swiper4.0 问题，动态加载的数据显示不正常

动态加载的数据，静态数据是20个slide 能对整齐。动态加载的数据只有15个却不能对齐

 var mySwiper = new this.$Swiper(".swiper-container2", {
        slidesPerView: 5, //一行显示5个
        slidesPerColumn: 2, //显示2行
        slidesPerGroup: 5, //每次滑动滚动的数量
        scrollbar: {
          el: "#sw2",
          dragSize: 53
        },
        draggable: false,
        observer: true, //修改swiper自己或子元素时，自动初始化swiper
        observeParents: false,
      });
      mySwiper.scrollbar.$el.css("height", "15px");
      mySwiper.scrollbar.$dragEl.css("background", "#F2414C");
      mySwiper.scrollbar.$el.css("width", "157px");
      mySwiper.scrollbar.updateSize();

            //结构
            <div class="swiper-container2">
      <div class="swiper-wrapper">
        <div
          class="swiper-slide"
          v-for="item in goodslist"
          :key="item.id"
          @click="toNew(item.id)"
        >
          <div class="box">
            <img :src="item.src" alt="这是图" />
          </div>
          <span>{{ item.name }}</span>
        </div>
      </div>
      <br />
      <div class="swiper-scrollbar" id="sw2"></div>
    </div>