Sorting array of multiple dictionaries - iphone

Question

My array contains three dictionaries per object of the array.
{
avg = {
avg1 = 50;
avg2 = 60;
};
posts = {
alcoholContent = 450;
name = "BBB";
origin = United States;
};
reviews = {
rev1 = "Test review 1";
rev2 = "Test review 2";
};
}
{
avg = {
avg1 = 30;
avg2 = 20;
};
posts = {
alcoholContent = 550;
name = "AAA";
origin = United States;
};
reviews = {
rev1 = "Test review 1";
rev2 = "Test review 2";
};
}
I want to sort array acceding by key "name" (of post dictionary).
How can I do it?
I tried normal sorting methods using sort descriptors, but did not work

Answer 1

Try sortUsingComparator:
[array sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
NSDictionary *dict1 = obj1;
NSDictionary *dict2 = obj2;
NSString *string1 = [[dict1 objectForKey:#"posts"] objectForKey:#"name"];
NSString *string2 = [[dict2 objectForKey:#"posts"] objectForKey:#"name"];
return [string1 compare:string2];
}];