Multiple methods named "setLength" found - ios

Question

I have this code:
[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] setLength:0];
and it is repeated three times
#pragma mark MyURLConnection delegate methods
- (void)connection:(MyURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
NSLog(#"Response received...");
[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] setLength:0];
}
- (void)connection:(MyURLConnection *)connection didReceiveData:(NSData *)data {
NSLog(#"Receiving data...");
[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] appendData:data];
}
- (void)connectionDidFinishLoading:(MyURLConnection *)connection {
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
NSLog(#"Request Succeeded! Received %d bytes of data",[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] length]);
//do something with data
NSString *response = [[NSString alloc] initWithData:[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] encoding:NSASCIIStringEncoding];
NSLog(#"HTTP Response: %#",response);
if(connection.tag == APNRegisterURLConnection) {
if([response isEqualToString:kPushNotificationRegistrationSuccess])
[self.userNotifications setObject:[NSNumber numberWithBool:TRUE] forKey:kRegistered];
else if ([response isEqualToString:kPushNotificationReRegistrationSuccess]){
[self.userNotifications setObject:[NSNumber numberWithBool:TRUE] forKey:kRegistered];
NSUUID *udid = [[UIDevice currentDevice] identifierForVendor];
NSString *httpBody = [NSString stringWithFormat:#"udid=%#",udid];
NSString *url = [kRequestURLAddress stringByAppendingString:#"updatenotifications.php"];
[self postRequestForURL:url withParameters:httpBody andTag:UpdateNotificationsURLConnection andPassingData:nil andOptionalMethod:#selector(displayUIActivityIndicatorView)];
}
else {
[self alertWithTitle:#"Error configuring push notifications" andMessage:kUnknownErrorAlertMessage];
}
}
else if(connection.tag == AddNotificationURLConnection) {
if([response isEqualToString:kPushNotificationAdditionSuccess]){
[[self.userNotifications valueForKey:kNotifications] addObject:connection.passingData];
[self.tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationNone];
}
else {
[self alertWithTitle:#"Error adding notification" andMessage:kUnknownErrorAlertMessage];
}
}
else if(connection.tag == DeleteNotificationURLConnection) {
if([response isEqualToString:kPushNotificationDeletionSuccess]){
[[self.userNotifications valueForKey:kNotifications] removeObjectAtIndex:[connection.passingData row]];
[self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:connection.passingData] withRowAnimation:UITableViewRowAnimationFade];
}
else {
[self alertWithTitle:#"Error deleting notification" andMessage:kUnknownErrorAlertMessage];
}
}
else if(connection.tag == UpdateNotificationsURLConnection) {
if(![response isEqualToString:#"error selecting udid"]){
//load notifications with myurlconnection, since internet is required to add items locally, logical sync is syncing everything to match the database
//sample format for list of notifications
// (int)periodindex (int)timeindex|(int)periodindex2 (int)timeindex2|(int)periodindex3 (int)timeindex3 (sorted by period index
// i.e. --> 0 13|2 6|4 11|4 6|9 4
NSArray *unparsedNotifications = [response componentsSeparatedByString:kNotificationDelimeter];
NSMutableArray *parsedNotifications = [NSMutableArray arrayWithCapacity:[unparsedNotifications count]];
int x;
if(!([[unparsedNotifications objectAtIndex:0] isEqualToString:#""] && [unparsedNotifications count] == 1)) {//no hits in database
NSArray *notificationStringArray;
Notification *parsed;
for (x=0; x<[unparsedNotifications count]; x++) {
notificationStringArray = [[unparsedNotifications objectAtIndex:x] componentsSeparatedByString:kElementDelimeter];
parsed = [Notification withPeriod:[[notificationStringArray objectAtIndex:0] intValue] andTime:[[notificationStringArray objectAtIndex:1] intValue]];
[parsedNotifications addObject:parsed];
}
NSLog(#"number of notifications in database = %d",[parsedNotifications count]);
}
//add missing notifications to array
Notification *value;
for(x=0;x<[parsedNotifications count];x++){
value = [parsedNotifications objectAtIndex:x];
if(![[self.userNotifications valueForKey:kNotifications] containsObject:value]){
[[self.userNotifications valueForKey:kNotifications] addObject:value];
NSLog(#"Adding notification with period:%# and time:%#",[value periodString],[value timeString]);
}
}
//delete objects in local array that are missing from online, reversed in order to remove largest indices and rows so that issue does not arise from looping through an array that has been changed
for(x=[[self.userNotifications valueForKey:kNotifications] count]-1;x>=0;x--){
value = [[self.userNotifications valueForKey:kNotifications] objectAtIndex:x];
if(![parsedNotifications containsObject:value]){
NSLog(#"Deleting notification with period:%# and time:%#",[value periodString],[value timeString]);
[[self.userNotifications valueForKey:kNotifications] removeObjectAtIndex:x];
}
}
[self.tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationNone];
}
else
[self alertWithTitle:kDefaultAlertTitle andMessage:kUnknownErrorAlertMessage];
}
[self cleanUpAfterRequest:connection.tag];
[response release];
[connection release];
[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] setLength:0];
}
-(void)cleanUpAfterRequest:(int)connectionType{
if(connectionType == AddNotificationURLConnection){
self.tableView.allowsSelection = TRUE;
self.tableView.allowsSelectionDuringEditing = TRUE;
}
else if(connectionType == DeleteNotificationURLConnection){
self.view.userInteractionEnabled = TRUE;
}
else if(connectionType == UpdateNotificationsURLConnection){
[[self.view viewWithTag:5] removeFromSuperview];
}
}
- (void)connection:(MyURLConnection *)connection didFailWithError:(NSError *)error {
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
NSString *failingKey = nil;
//IF_PRE_IOS4(failingKey = NSErrorFailingURLStringKey;);
failingKey = NSURLErrorFailingURLStringErrorKey;
NSLog(#"Connection failed! Error - %# %#", [error localizedDescription], [[error userInfo] objectForKey:failingKey]);
[self cleanUpAfterRequest:connection.tag];
[self alertWithTitle:kDefaultAlertTitle andMessage:kDefaultAlertMessage];
[connection release];
[[self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] setLength:0];
}
Xcode returns the error "Multiple methods named "setLength" found."
Any ideas on what I should do to fix it?

Answer 1

Assign the results of [self.receivedData objectForKey:[NSNumber numberWithInt:connection.tag]] to a variable of the proper type. Then call the setLength: method on that variable.
BTW - use modern syntax:
self.receivedData[#(connection.tag)];
The #(connection.tag) replaces the use of [NSNumber numberWithInt:connection.tag] and self.receivedData[xxx] replaces the use of objectForKey:.