Display nested list from nested xml sencha touch

[MyRune]

Here is my xml format:\[code\]<countries> <country name="countryname1" id="0"> <state name="statename1" cid="0" sid="0"> . .//some data . </state> <state name="statename2" cid="0" sid="0"> . .//some data . </state> <state name="statename3" cid="0" sid="0"> . .//some data . </state> <country name="countryname2" id="0"> <state name="statename1" cid="0" sid="0"> . . .</countries>\[/code\]Now I have to show a list containing countries, and on selecting a country another list should open showing the states of the country.Till now i am able to show the county list. But i do not know how should i deal with the nested data.my query is:1) What model should i use for this xml... should it be nested model ??2) If i have to use TreeStore and NestedList, then how shall i do it.. what root should i put in reader in Store as i have to read <country> and then <state>... please help me with some sample code