code: function() {
  		var self = this,
  			node = this.getUI(),
  			ni = node.css('z-index');
  		if (ni && ni !== 'auto' && ni !== 'inherit') {
  			self.zIndex = ni;
  		} else {
  			node.parents().each(function(i, n) {
  				var z = $(n).css('z-index');
  				if (z !== 'auto' && z !== 'inherit' && (z = parseInt(z))) {
  					self.zIndex = z;
  					return false;
  				}
  			});
  		}
  	}
docs: calculate elFinder node z-index
  
  @return void