我在一个应用程序中使用Backbone.js。我将段与url相关联。因此，一个段可以包含许多url，一个给定的url可以在任何段中。有一个url窗格和一个段窗格。问题是突出显示部分。因此，当我单击一个段时，我想突出显示它的url。我已将一个页面上显示的url数量限制为200。如果超过200个url'我们只向用户显示前200个网址，其余的网址，用户只使用实时搜索来找到他要找的网址。问题是，当网址少于200个时，当我点击一个分段时，高亮显示就起作用了。当网址超过200个时，当用户点击一个分段时，突出显示不起作用。我在集合上使用切片，如果有超过200个url，只突出显示前200个，但这不起作用。以下是代码片段。有人对如何解决这个问题有什么好的建议吗？
在toggleSelection函数的SegmentView.js中：

toggleSelection: function() {
    var max = 200;
   //get the urls
    var urls = this.App.segmentUrlCollection.urlsForSegment(this.model);
    var pixels = this.App.segmentPixelCollection.pixelsForSegment(this.model);
    if (this.selected) {
      this.deselect();
      this.selected = false;
      this.$('.summary').removeClass('selected');
      this.App.segmentCollection.each(function(segment){
       if (segment.get('name') == "Unmapped"){
          segment.view.$('.summary').addClass('unmapped');
        }
      });

    //If there are more than 200 urls in url Collection just highlight the first 200.
        if (this.App.urlCollection.size  > 200) {
          //problem?
            this.App.urlCollection.slice(0,199).each(function(url) {
                if (url.view.App.isUrlUnmapped(url)) {
                    url.view.$('.summary').addClass('unmapped');
                }
            });
        }
        else {
            this.App.urlCollection.each(function(url) {
                if (url.view.App.isUrlUnmapped(url)) {
                    url.view.$('.summary').addClass('unmapped');
                }
            });
        }
     //deselect the urls
       _(urls).each(function(url) {
        url.view.deselect();
      });
      _(pixels).each(function(pixel) {
        pixel.view.deselect();
      });
    } else {
      this.App.segmentCollection.each(function(segment) {
        segment.view.selected = false;
        segment.view.deselect();
      });
          this.App.segmentCollection.each(function(segment){
       if (segment.view.$('.summary').hasClass('unmapped')){
          segment.view.$('.summary').removeClass('unmapped');
        }
      });
      //If there are more than 200 urls in url Collection just highlight the first 200.
        if (this.App.urlCollection.size  > 200) {
           //problem?
            this.App.urlCollection.slice(0,199).each(function(url) {
                if (url.view.$('.summary').hasClass('unmapped')) {
                    url.view.$('.summary').removeClass('unmapped');
                }
               // url.view.deselect();
            });
        }
        else {
            this.App.urlCollection.each(function(url) {
                if (url.view.$('.summary').hasClass('unmapped')) {
                    url.view.$('.summary').removeClass('unmapped');
                }
               // url.view.deselect();
            });
        }

 //If there are more than 200 urls in url Collection just highlight the first 200.
       if (this.App.urlCollection.size  > 200) {
         //problem?
            this.App.urlCollection.slice(0,199).each(function(url) {
                 url.view.deselect();
            });
        }
        else {
            this.App.urlCollection.each(function(url) {
                 url.view.deselect();

            });
        }

      this.App.pixelCollection.each(function(pixel) {
        pixel.view.deselect();
      });

      this.select();
      this.selected = true;
      this.$('.summary').addClass('selected');
       //select the urls
      _(urls).each(function(url) {
        url.view.select();
      });
      _(pixels).each(function(pixel) {
        pixel.view.select();
      });
    }

    return false;
  }