Question

I have a tap panel, and OpenLayers map on the page. I want to show one layer when one tap is active. How to do this? I mean how to do some action when tab active, and destroy this whan panel is no active?

Answer 1

you can listen to tabchange event as mentioned here http://docs.sencha.com/ext-js/4-0/#!/api/Ext.tab.Panel-event-tabchange
like this

{
 xtype:'tabpanel'
 //some other configs
 listeners:{
  tabchange:function(tabPabel,newCard, oldCard){
   //chek wether the newCard is same to what you wanted
   // and do whatever you wanna do
  }
 }
}