can't populate UITableView, source array valid - ios

Question

I can't make my table view show my data, the array has valid data by the NSLog output. I put a breakpoint at the beginning of tableView:cellForRowAtIndexPath: and it never get there. Any ideas why?
#import "ViewController.h"
#import "Ride.h"
#interface ViewController ()
#property (nonatomic, strong) NSMutableData *responseData;
#end
#implementation ViewController
#synthesize rideIds = _rideIds;
#synthesize rideNames = _rideNames;
- (void)viewDidLoad
{
[super viewDidLoad];
NSLog(#"viewdidload");
self.responseData = [NSMutableData data];
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
// http://www.strava.com/api/v1/segments/229781/efforts?best=true
// Efforts on segment by athlete limited by startDate and endDate
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://www.strava.com/api/v1/segments/229781/efforts?athleteId=11673&startDate=2012-02-01&endDate=2012-02-28"]];
//Leader Board on Segment all Athletes
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://www.strava.com/api/v1/segments/229781/efforts?best=true"]];
//Rides by Athlete
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://www.strava.com/api/v1/rides?athleteId=10273"]];
//Twitter Example
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://api.twitter.com/1/trends"]];
//Efforts by Ride
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://www.strava.com/api/v1/rides/77563/efforts"]];
//Effort Detail
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://www.strava.com/api/v1/efforts/688432"]];
//Google API Call
//NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://maps.googleapis.com/maps/api/place/search/json?location=-33.8670522,151.1957362&radius=500&types=food&name=harbour&sensor=false&key=AIzaSyAbgGH36jnyow0MbJNP4g6INkMXqgKFfHk"]];
/* dispatch_async(dispatch_get_main_queue(),^ {
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
} ); */
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if(theConnection){
self.rideIds = [[NSMutableArray alloc]init];
self.rideNames = [[NSMutableArray alloc] init];
} else {
NSLog(#"No Connection");
}
}
//Delegate methods for the NSURLConnection
//In order to download the contents of a URL, an application needs to provide a delegate object that, at a minimum, implements the following delegate methods: connection:didReceiveResponse:, connection:didReceiveData:, connection:didFailWithError: and connectionDidFinishLoading:.
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
NSLog(#"didReceiveResponse");
//This message can be sent due to server redirects, or in rare cases multi-part MIME documents.
//Each time the delegate receives the connection:didReceiveResponse: message, it should reset any progress indication and discard all previously received data.
[self.responseData setLength:0];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[self.responseData appendData:data];
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
NSLog(#"didFailWithError");
NSString *errorDescription = [error description];
// NSLog([NSString stringWithFormat:#"Connection failed: %#", errorDescription]);
NSLog(#"Connection failed: %#", errorDescription);
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
NSLog(#"connectionDidFinishLoading");
NSLog(#"Succeeded! Received %d bytes of data",[self.responseData length]);
// convert to JSON
NSError *myError = nil;
//NSDictionary *jsonRes = [NSJSONSerialization JSONObjectWithData:self.responseData options:NSJSONReadingMutableLeaves error:&myError];
NSDictionary *jsonResult = [NSJSONSerialization JSONObjectWithData:self.responseData options:NSJSONReadingMutableLeaves error:&myError];
NSDictionary *jsonRides =[jsonResult objectForKey:#"rides"];
// Show all values coming out of "rides" key
// Store ride id's and names on arrays for later display on tableview
for (NSDictionary *rides in jsonRides) {
[self.rideIds addObject:[rides objectForKey:#"id"]];
NSLog(#"id = %#", [rides objectForKey:#"id"]);
//NSLog(#"%#",self.rideIds);
[self.rideNames addObject:[rides objectForKey:#"name"]];
NSLog(#"name = %#", [rides objectForKey:#"name"]);
//NSLog(#"%#",self.rideNames);
}
NSLog(#"%#",self.rideIds);
NSLog(#"%#",self.rideNames);
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
// Show all values coming out of NSKSONSerialization
for(id key in jsonResult) {
id value = [jsonResult objectForKey:key];
NSString *keyAsString = (NSString *)key;
NSString *valueAsString = (NSString *)value;
NSLog(#"key: %#", keyAsString);
NSLog(#"value: %#", valueAsString);
}
// extract specific value...
// NSArray *results = [res objectForKey:#"results"];
/*NSArray *results = [res objectForKey:#"rides"];
for (NSDictionary *result in results) {
NSData *athleteData = [result objectForKey:#"name"];
NSLog(#"Ride name: %#", athleteData);
}*/
/* dispatch_async(dispatch_get_main_queue(),^ {
[self.rideTableView reloadData];
} ); */
[self.rideTableView reloadData];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSLog(#"tableView:numberOfRowsInSection: ");
//return self.rideIds.count;
NSLog(#"%u",self.rideNames.count);
return 3;
}
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSLog(#"tableView:cellForRowAtIndexPath: ");
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if( nil == cell ) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.textLabel.text= [self.rideNames objectAtIndex:indexPath.row];
return cell;
}
- (void)tableView:(UITableView *)tv
didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tv deselectRowAtIndexPath:indexPath animated:YES];
}
#end
NSLog content:
2012-08-18 18:47:29.497 WebServiceCall[10387:c07] viewdidload
2012-08-18 18:47:29.503 WebServiceCall[10387:c07] tableView:numberOfRowsInSection:
2012-08-18 18:47:29.503 WebServiceCall[10387:c07] 0
2012-08-18 18:47:29.504 WebServiceCall[10387:c07] tableView:cellForRowAtIndexPath:
2012-08-18 18:47:29.506 WebServiceCall[10387:c07] *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 0 beyond bounds for empty array'
*** First throw call stack:
(0x14b6022 0xeb6cd6 0x14a2d88 0x395d 0xb3c54 0xb43ce 0x9fcbd 0xae6f1 0x57d42 0x14b7e42 0x1d87679 0x1d91579 0x1d164f7 0x1d183f6 0x1da5160 0x17e84 0x18767 0x27183 0x27c38 0x1b634 0x13a0ef5 0x148a195 0x13eeff2 0x13ed8da 0x13ecd84 0x13ecc9b 0x17c65 0x19626 0x22fd 0x2265 0x1)
terminate called throwing an exception(lldb)
UPDATE: It seems that after passing through viewDidLoad it jumps right into tableview:numberOfRowsInSection method skipping all the 4 methods for handling NSURLConnection (where I updated my arrays).
My view controller is both delegate of my NSURLConnection AND my tableView. It seems that it's running first the tableView methods. Any suggestions as to how to make it run the NSURLConnection methods first ?

Answer 1

Two things you could try -- First, log self.rideIds.count in your numberOfRowsInSection method to make sure it's not returning 0. Second, at the end of your connectionDidFinishLoading method, put in a [tableView reloadData] (or whatever the outlet to your table view is), that should take care of the problem of the table view methods being called before your connection is done.
After Edit: The error "-[__NSArrayM objectAtIndex:]: index 0 beyond bounds for empty array" is being caused by the "return 3" in your numberOfRowsInSection method. When the app starts up the table view will try to populate itself before your connection returns any results, so numberOfRowsInSection should return 0 not 3 the first time through, which it will do if you put back the return self.rideIds.count line. If you do the reloadData at the end of the connection delegate methods, then the array will be populated and the table view should work properly.

Answer 2

Where is tableView:numberOfSectionsInTableView:? Perhaps that is returning 0 although the default is 1 if not set; You also need to set delegate and dataSource on your tableView.