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iphoneobjective-cmkmapviewcllocation

CLLocationCoordinate2D without knowing how many will be in the array?


I need to build an array using something like the following:

CLLocationCoordinate2D  points[4];


    points[0] = CLLocationCoordinate2DMake(41.000512, -109.050116);

    points[1] = CLLocationCoordinate2DMake(41.002371, -102.052066);

    points[2] = CLLocationCoordinate2DMake(36.993076, -102.041981);

    points[3] = CLLocationCoordinate2DMake(36.99892, -109.045267);

Problem is, I will never know how many items are going to be in the array, so I can specify the count. Is there a way to create a CLLocationCoordinate2D array, and just insert new coordinates without knowing what the final total will be?

EDIT: My final goal is to use the coordinates to make an MKPolyline, using the polylineWithCoordinates method which needs a CLLocationCoordinate2D array.


Solution

  • // unpacking an array of NSValues into memory
    CLLocationCoordinate2D *points = malloc([mutablePoints count] * sizeof(CLLocationCoordinate2D));
    for(int i = 0; i < [mutablePoints count]; i++) {
        [[mutablePoints objectAtIndex:i] getValue:(points + i)];
    }
    
    MKPolyline *myPolyline = [MKPolyline polylineWithCoordinates:points count:[mutablePoints count]];
    free(points);