Converting table view to have sections - iphone

Question

I have a table view, which has its data source from an array that contains names of people.
Now to make it easy to find people, I want to section the table view so that it has the letter A-Z on the right hand side, just like the Address Book app.
But my current array just contains a collection of NSStrings. How do I split them so that they are grouped by the first letter of the names? Is there any convenient way to do it?
EDIT: If anyone's interested in my final code:
NSMutableArray *arrayChars = [[NSMutableArray alloc] init];
for (char i = 'A'; i <= 'Z' ; i++) {
NSMutableDictionary *characterDict = [[NSMutableDictionary alloc]init];
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
for (int k = 0; k < [myList count]; k++) {
NSString *currentName = [[friends objectAtIndex:k] objectForKey:#"name"];
char heading = [currentName characterAtIndex:0];
heading = toupper(heading);
if (heading == i) {
[tempArray addObject:[friends objectAtIndex:k]];
}
}
[characterDict setObject:tempArray forKey:#"rowValues"];
[characterDict setObject:[NSString stringWithFormat:#"%c",i] forKey:#"headerTitle"];
[arrayChars addObject:characterDict];
[characterDict release];
[tempArray release];
}
At the end of the function I'll have:
arrayChars [0] = dictionary(headerTitle = 'A', rowValues = {"adam", "alice", etc})
arrayChars[1] = dictionary(headerTitle = 'B', rowValues = {"Bob", etc})
Thank you everyone for your help!

Answer 1

You can use a dictionary to sort them, so create an array with all the letters you want to sort and a array with nil objects to initialize the dictionary
NSArray *names = #[#"javier",#"juan", #"pedro", #"juan", #"diego"];
NSArray *letters = #[#"j", #"p", #"d"];
NSMutableArray *objects = [[NSMutableArray alloc] init];
for (NSInteger i = 0; i < [letters count]; ++i)
{
[objects addObject:[[NSMutableArray alloc] init]];
}
NSDictionary *dictionary = [[NSDictionary alloc] initWithObjects:objects forKeys:letters];
Then you must find the first letter if the word and put that word into the corresponding key in the dictionary
for (NSString *name in names) {
NSString *firstLetter = [name substringToIndex:1];
for (NSString *letter in letters) {
if ([firstLetter isEqualToString:letter]) {
NSMutableArray *currentObjects = [dictionary objectForKey:letter];
[currentObjects addObject:name];
}
}
}
To check you can print directly the dictionary
NSLog(#"%#", dictionary);
Then is your work to fill your sections in the tableview using the dictionary