code: function setBarSize(_size) {
              var barMinSize = this.barMinSize || 20
              var size = _size
  
              if (size > 0 && size < barMinSize) {
                  size = barMinSize
              }
  
              if (this.bar) {
                  css(this.bar, this.origin.size, parseInt(size, 10) + 'px')
              }
          }
docs: Updating height or width of bar