Best way to implement address book autocompletion on iPhone?

Question

I'm wondering what is the best (fastest and simplest) way to have a textfield auto complete with iPhone's address book contacts information.

Would access the address book each time a key is pressed fast enough ? Or do I have to load everything in my own local database (CoreData typically) ? Another way would be to load everything in memory at each app launch. Any experience regarding the access speed of the adress book ?

ADDED: I'd like to avoid having to load a local copy of the address book content because it's not only more code to write but you also need to sync your local copy when address book is modified.

What kind of contacts information will appear in the auto complete fields ? — Michaël, Mar 08 '11 at 10:52
Names (first and last), email or phone number. The user should be able to use any of those details to select a contact — CodeFlakes, Mar 08 '11 at 11:56

score 2 · Accepted Answer · answered Mar 09 '11 at 10:36

2

For super fast character by character retrieval, the approach you need is called a Directed acyclic word graph.

answered Mar 09 '11 at 10:36

Max MacLeod

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score 1 · Answer 2 · answered Mar 08 '11 at 22:52

Would access the address book each time a key is pressed fast enough ?

Probably not for large books but test it an see. You could call ABAddressBookCopyPeopleWithName with each additional character and see what pops up. You would most likely need to require a minimum number of characters e.g. 3 before performing the search because otherwise you would get a lot of returns for each the first character.

However, I don't think there are functions for phone numbers and addresses.

The alternative would be to create a tree data structure with letters and numbers that would branch out to a leaf containing an ABRecordID of a particular AddressBook entry. Using Core Data relationships is a quick and easy way to do that. Of course, you would have to update your tree continuously.

Best way to implement address book autocompletion on iPhone?

2 Answers2

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