我使用光滑的js为图像的滑块视图。
这是我的代码。

<div class="slider_wrap add-remove">
    <%= f.fields_for :images do |image_form| %>
      <%#= render 'images_fields', :f => image_form %>
        <div>
          <%= image_tag image_form.object.picture.url,:class=>"drop_down_link even img_prev" %>
        </div>
        <div class="image_upload_div">
          <div class="image-upload">
            <label>
              <i class="fa fa-cloud-upload">
                <%= image_form.file_field :picture ,:'data-role'=>"none",:onchange=>"readURL(this);" , :accept => 'image/jpeg , image/png' %>
              </i>
            </label>
          </div>
        </div>
    <% end %>
    <%= f.link_to_add "Add a picture", :images ,:id=>"add_pic" ,:class=>"js-add-slide", :style=>"display: none;"%>
</div>

<script>
function silder(){
    slideIndex = 0;
      $('.add-remove').slick({
        slidesToShow: 2,
        slidesToScroll: 2
      });
      $('.js-add-slide').on('click', function() {
        $('.add-remove').slick('slickAdd');
      });

      $('.js-remove-slide').on('click', function() {
        $('.add-remove').slick('slickRemove');
      });
});
function readURL(input) {
  if (input.files && input.files[0]) {
    var reader = new FileReader();
    reader.onload = function (e) {
    $('.img_prev').last()
      .attr('src', e.target.result)
    };

    reader.readAsDataURL(input.files[0]);

    setTimeout(function(){
      $('#add_pic').trigger('click');
      silder();
    }, 100);
  }
}
</script>

现在有了这个代码，我得到了滑块工作，但它不来正确的我得到错误：
未捕获的类型错误：无法读取空值的属性"add"