Question

This is my JSON output

{"activitiesList":{"auid":"19UG9IZ","comments":"Please enter Description","createDate":"09/19/2012 07:32:56 AM","id":"19UG9IZ","owner":"04256CRM","response":"Missing Response","status":"Assigned","type":"Request Action"}}

The code below works when I have multiple activitiesList and not for above output, which has single activitiesList

@try {
    NSError* error;
    NSDictionary* json = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&error];
    NSArray* activityListFromSiebel = [json objectForKey:@"activitiesList"]; //2
    NSLog(@" Count is %d", [activityListFromSiebel count]);
    for (int i = 0; i < [activityListFromSiebel count]; i++) {
        //if ([activityListFromSiebel count] > 1) {
            NSDictionary* completeActivity = [activityListFromSiebel objectAtIndex:i];

            ObjActivityData *dataActivity = [[ObjActivityData alloc] init];
            dataActivity.activityUID      = [completeActivity objectForKey:@"auid"];
            dataActivity.activitytype     = [completeActivity objectForKey:@"type"];
            dataActivity.activityStatus   = [completeActivity objectForKey:@"status"];
            dataActivity.activityOpenedDt = [completeActivity objectForKey:@"createDate"];
            dataActivity.activityDueDt    = @"";
            dataActivity.activityDesc     = [completeActivity objectForKey:@"comments"];
            dataActivity.activityResponse = [completeActivity objectForKey:@"response"];
            [Activities addObject:dataActivity];
            dataActivity = nil;
        //}
    }
    [self.tableView reloadData];
} @catch (NSException * e) {
    NSLog(@"catching %@ reason %@", [e name], [e reason]);
} @finally {
    NSLog(@"finally");
}

try/catch error thrown is NSInvalidArgumentException reason -[__NSCFArray length]: unrecognized selector sent to instance 0x68c8e90.
Should I parse the JSON output differently if the output is just 1 array element. Appreciate help

Thanks

Answer 1

Do this,

id obj = [json objectForKey:@"activitiesList"];
NSArray* activityListFromSiebel = nil;

if ([obj isKindOfClass:[NSArray class]]) {
    activityListFromSiebel = (NSArray *)obj;
} else {
    activityListFromSiebel = [NSArray arrayWithObject:obj];
}

The problem is that when you are trying to use your code, you are assuming that [json objectForKey:@"activitiesList"]; is an array, but actually it is just a dictionary when only a single item is present. Either you can by pass your for loop and convert your dictionary to ObjActivityData object in the else part, or just add this as a quick fix before the for loop which you are using now.

So your code will look like this,

NSError* error;
NSDictionary* json = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&error];

id obj = [json objectForKey:@"activitiesList"];
NSArray* activityListFromSiebel = nil;

if ([obj isKindOfClass:[NSArray class]]) {
    activityListFromSiebel = (NSArray *)obj;
} else {
    activityListFromSiebel = [NSArray arrayWithObject:obj];
}

NSLog(@" Count is %d", [activityListFromSiebel count]);
for (int i = 0; i < [activityListFromSiebel count]; i++) {
    //if ([activityListFromSiebel count] > 1) {
        NSDictionary* completeActivity = [activityListFromSiebel objectAtIndex:i];

        ObjActivityData *dataActivity = [[ObjActivityData alloc] init];
        dataActivity.activityUID      = [completeActivity objectForKey:@"auid"];
        dataActivity.activitytype     = [completeActivity objectForKey:@"type"];
        dataActivity.activityStatus   = [completeActivity objectForKey:@"status"];
        dataActivity.activityOpenedDt = [completeActivity objectForKey:@"createDate"];
        dataActivity.activityDueDt    = @"";
        dataActivity.activityDesc     = [completeActivity objectForKey:@"comments"];
        dataActivity.activityResponse = [completeActivity objectForKey:@"response"];
        [Activities addObject:dataActivity];
        dataActivity = nil;
    //}
}
[self.tableView reloadData];