Create MKPolyline with only recent CLLocations

Question

My app loads the user's past polylines and displays them on the map. Then the app starts tracking and a straight line is drawn from the last updated coordinate to the first, thereby connecting the two separate lines when they should be separate (shown here

I want to remove this straight line, so I'm thinking the easiest way would be to discard coordinates that are outside a set time frame (e.g 1 minute), so polylines on the map remain separate. I'm not sure how to do this though... I'm a beginner so any suggestions would be much appreciated!

I use this code when loading the past polyline

(IBAction)didClickLoadCoordinates:(id)sender {
// get a reference to the appDelegate so you can access the global managedObjectContext
AppDelegate *appDelegate = [UIApplication sharedApplication].delegate;

NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Route"];
NSError *error;
id results = [appDelegate.managedObjectContext executeFetchRequest:request error:&error];

if ([results count]) {
    polyLine = (Route *)(results[0]);
    NSArray *coordinates = polyLine.coordinates;
    int ct = 0;
    for (CLLocation *loc in coordinates) {
        NSLog(@"location %d: %@", ct++, loc);
    }


    // this copies the array to your mutableArray
    _locationsArray = [coordinates mutableCopy];

}

NSInteger numberOfSteps = _locationsArray.count;

//convert to coordinates array to construct the polyline

CLLocationCoordinate2D clCoordinates[numberOfSteps];
for (NSInteger index = 0; index < numberOfSteps; index++) {
    CLLocation *location = [_locationsArray objectAtIndex:index];
    CLLocationCoordinate2D coordinate2 = location.coordinate;
    clCoordinates[index] = coordinate2;
}

MKPolyline *routeLine = [MKPolyline polylineWithCoordinates:clCoordinates count:numberOfSteps];
[_mapView addOverlay:routeLine];

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations{

And this code to just normally update the cllocations and make the polyline

//get the latest location
CLLocation *currentLocation = [locations lastObject];


//get latest location coordinates
CLLocationDegrees latitude = currentLocation.coordinate.latitude;
CLLocationDegrees longitude = currentLocation.coordinate.longitude;
CLLocationCoordinate2D locationCoordinates = CLLocationCoordinate2DMake(latitude, longitude);

//zoom map to show users location
MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(locationCoordinates, 2000, 2000);
MKCoordinateRegion adjustedRegion = [_mapView regionThatFits:viewRegion];
[_mapView setRegion:adjustedRegion animated:YES];


    //store latest location in stored track array
    [_locationsArray addObject:currentLocation];


//create cllocationcoordinates to use for construction of polyline
NSInteger numberOfSteps = _locationsArray.count;
CLLocationCoordinate2D coordinates[numberOfSteps];
for (NSInteger index = 0; index < numberOfSteps; index++) {
    CLLocation *location = [_locationsArray objectAtIndex:index];
    CLLocationCoordinate2D coordinate2 = location.coordinate;
    coordinates[index] = coordinate2;
}

MKPolyline *routeLine = [MKPolyline polylineWithCoordinates:coordinates count:numberOfSteps];
[_mapView addOverlay:routeLine];

NSLog(@"%@", _locationsArray);

Switchman

Simplest way to keep lines separate is to add them as separate overlays. You haven't shown any code or explained exactly what you're having difficulty with so it's hard to give more details. – Pah

Basically I load past user routes when the app launches, persisting past polylines. So when the app reopens, it begins tracking user location again. The problem is, the user will have a new location at this point, and a line is drawn from last updated location to the current location (see here). I've updated the question with the code I use in the CLLocation Manager – Switchman