code: function(key) {
  		var node = this.getNodeByKey(key);
  		if(node){
  			node.setActive();
  		}else if(this.activeNode){
  			this.activeNode.setActive(false);
  		}
  		return node;
  	}
docs: Activate node with a given key and fire focus and activate events.
  
  A prevously activated node will be deactivated.
  If activeVisible option is set, all parents will be expanded as necessary.
  Pass key = false, to deactivate the current node only.
  @param {string} key
  @returns {FancytreeNode} activated node (null, if not found)