UITabelView doesn't get updated with new content from server side - iphone

Question

I have an app which has an UITabelView which gets its content from a server side.In my app i read the content from the server each 30 seconds....for that I use a NSTimer.
This NSTimer gets initialized when I load the view which contains the UITableView and it is invalidated when I leave this view.
My problem is this:
if on the server side the content for the UITableView is updated with new item and the JSON received in the iphone app as a response to a request to the server contains that item....the UITableView that appears on the screen is still not updated.
Here is how I did it:
//the timer is started when this view is loaded and the method repeatServerRequest is called
- (void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
if(playlistTimer == nil)
playlistTimer = [NSTimer scheduledTimerWithTimeInterval:30.0 target: self selector: #selector(repeatServerRequest) userInfo: nil repeats: YES];
}
//the method repeatServerRequest starts a new thread in the background which does a request //to server for downloadeding the content
- (void) repeatServerRequest{
[NSThread detachNewThreadSelector:#selector(backgroundThinking) toTarget:self withObject:nil];
}
- (void) backgroundThinking{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
NSURL *url = [NSURL URLWithString:#"a link to server"];
ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url];
[request setDelegate:self];
[request startAsynchronous];
[pool release];
}
///when the response from server comes in these methods are called:
- (void)requestFinished:(ASIHTTPRequest *)request
{
[self performSelectorOnMainThread:#selector(didFindAnswer:) withObject:request waitUntilDone:YES];
}
- (void)requestFailed:(ASIHTTPRequest *)request
{
NSError *error = [request error];
NSLog(#"the value of error %#", error);
}
- (void) didFindAnswer:(ASIHTTPRequest *) request{
NSLog(#"update tabel");
SBJSON *parser = [[SBJSON alloc] init];
NSString *responseString = [request responseString];
NSArray *statuses = [parser objectWithString:responseString error:nil];
streams = [statuses valueForKey:#"_playLists"];
[parser release];
playList = [[NSMutableArray alloc] init];
idList = [[NSMutableArray alloc] init];
int ndx;
for (ndx = 0; ndx<streams.count; ndx++) {
NSDictionary *stream = (NSDictionary *)[streams objectAtIndex:ndx];
[playList addObject:[stream valueForKey:#"name"]];
[idList addObject:[stream valueForKey:#"id_playlist"]];
}
NSLog(#"playList %#", playList);
oneview = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 480, 320)];
tableViewPlaylist =[[UITableView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) style:UITableViewStylePlain];
tableViewPlaylist.bounces=NO;
tableViewPlaylist.backgroundColor=[UIColor clearColor];
[tableViewPlaylist setDelegate:self];
[tableViewPlaylist setDataSource:self];
}
So when I update the content on server side, the JSON thet I get as a response on server side is updated but the UITAbelView is not, UNLESS I RUN AGAIN MY APP.Any idea why?

Answer 1

Two main problems:
You are creating a new UITableView every time the server updates. This is unnecessary.
Even if you wanted a new tableView, you are not adding it as a subview of the main view.
What you should do instead is don't create a new tableView at all. After you've updated the data model call [tableView reloadData] on the main thread. Your table will update and all is good. Assuming you have everything configured correctly and it sounds like you do if you see the expected data when you launch the app.