docs: function() {
              this.$button = $(this.options.templates.button).addClass(this.options.buttonClass);
  
              // Adopt active state.
              if (this.$select.prop('disabled')) {
                  this.disable();
              }
              else {
                  this.enable();
              }
  
              // Manually add button width if set.
              if (this.options.buttonWidth && this.options.buttonWidth !== 'auto') {
                  this.$button.css({
                      'width' : this.options.buttonWidth
                  });
                  this.$container.css({
                      'width': this.options.buttonWidth
                  });
              }
  
              // Keep the tab index from the select.
              var tabindex = this.$select.attr('tabindex');
              if (tabindex) {
                  this.$button.attr('tabindex', tabindex);
              }
  
              this.$container.prepend(this.$button);
          }