João Prado Maia gave a presentation on iOS development. He discussed using table views and SQLite to build an app with a drill down interface. He also covered using the ASIHTTPRequest library to make API calls and load data dynamically. Finally, he discussed using JSON as a format for serializing and transmitting data from web services to mobile clients.

1. João Prado Maia Ipanema Labs, LLC http://ipanemalabs.com UIKit Programming (and some network stuff too)

2. Who? Web programmer by day, iOS developer by night. Consultant on iOS development projects. Contact me at http://ipanemalabs.com Few apps on App Store since 2008. Personal site at http://pessoal.org

3. Tonight’s session Hands on Lots of code to go through Ask questions at any time!

4. Table views Standard classes: UINavigationController UIViewController UITableViewController Goal: build a simple app with a drill down interface.

5. Saving data to SQLite FMDB! http://code.google.com/p/flycode/source/browse/trunk/fmdb Open source wrapper on top of SQLite. Actively maintained; easy to work with. Goal: change previous example to load information from a SQLite database.

6. Dealing with an API ASIHTTPRequest http://allseeing-i.com/ASIHTTPRequest/ Much more convenient than NSURLConnection. Open source; very easy to use. Goal: modify previous example to load data from an API dynamically.

7. ASIHTTPRequest Advanced features available to you in an easy to use wrapper: Download data to memory or directly to file Easy to upload files through POST Automatic progress indicators for downloads/uploads Asynchronous/Synchronous requests and persistent connections etc Good documentation with lots of examples

8. ASIHTTPRequest (2) - (IBAction)grabURL:(id)sender { NSURL *url = [NSURL URLWithString:@"http://allseeing-i.com"]; ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request startSynchronous]; NSError *error = [request error]; if (!error) { NSString *response = [request responseString]; } }

9. ASIHTTPRequest (3) - (IBAction)grabURLInBackground:(id)sender { NSURL *url = [NSURL URLWithString:@"http://allseeing-i.com"]; ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request setDelegate:self]; [request startAsynchronous]; } - (void)requestFinished:(ASIHTTPRequest *)request { // Use when fetching text data NSString *responseString = [request responseString]; // Use when fetching binary data NSData *responseData = [request responseData]; } - (void)requestFailed:(ASIHTTPRequest *)request { NSError *error = [request error]; }

10. JSON JSON - JavaScript Object Notation Serialization format much less verbose than XML Perfect for web services that need to return information for mobile clients iOS library: json-framework http://code.google.com/p/json-framework/ Open source (BSD) library

11. JSON (2) Serialized hash/dictionary: {“key1”: “value1”, “key2”: “value2”} Serialized array: [“value1”, “value2”, “value3”] Mixed object (array of dictionaries): [{“name”: “Joao”, “ssn”:”12345678”}, {“name”:”Barry”, “ssn”:”98765432”}]

12. JSON parsing example NSArray *list; NSString *jsonString = @"[\"Meetup\", \"is\", \"cool\"]"; list = [jsonString JSONValue]; NSLog(@"first entry: %@", [list objectAtIndex:0]); NSLog(@"second entry: %@", [list objectAtIndex:1]); NSLog(@"third entry: %@", [list objectAtIndex:2]); [json release];

13. Q&A Any questions?