Sencha touch nestedlist click event without switching card

listeners: {
itemtap: function(list, index, item, e) {
//is home menu
if (list == this.items.getAt(0)) {
switch(index) {
case 0: //first menu
                                        //things to do for this detected menu
                                        //get the tabpanel and switch the card of tabpanel
Ext.getCmp("divTabPanel").setActiveItem(1);
                                        //call nestedlist to go back...
this.onBackTap();
break;
}
}//if is home menu
},

//...
}