cannot add another object into an array containing different objects

Someone please help.

I am a noob here who has just created an array to contain all my polyclinics object. Now I need to add in a user object (patientDetail object) into this array. But no matter how i modify the viewDidLoad method, something just seems not quite right.. i cannot populate all the points.. only when i remove all codes that deal with the user object then it works.. Some1 please take a look at the method below and advise? I need to add in the patientDetail object and populate it with the rest of the polyclinics...

thanks for reading =(

- (void)viewDidLoad {
        [super viewDidLoad];

        _annotation2 = [[NSMutableArray alloc] init];

    CLLocation *userLoc = _mapView.userLocation.location;
        CLLocationCoordinate2D userCoordinate = userLoc.coordinate;

    NSLog(@"user latitude = %f",userCoordinate.latitude);
    NSLog(@"user longitude = %f",userCoordinate.longitude);



   _annotations=[[NSMutableArray alloc] init];
       _listOfPolyClinics = [[NSMutableArray alloc] init];

PatientDetails *patientDetails = [[PatientDatabase database] 
                                  patientDetails:_nric];

for (PolyClinics *polyclinics in [[PatientDatabase database] 
                                  polyClinics]){
    [_listOfPolyClinics addObject:polyclinics];
}

[_listOfPolyClinics addObject:patientDetails];



for (PolyClinics *polyclinics1 in _listOfPolyClinics){
    MyAnnotation* myAnnotation=[[MyAnnotation alloc] init];

    if ([polyclinics1 isKindOfClass:[PatientD开发者_高级运维etails class]]){ 
        CLLocationCoordinate2D theCoordinate3;
        theCoordinate3.longitude = patientDetails.longitude;
        theCoordinate3.latitude = patientDetails.latitude;

        myAnnotation.coordinate = theCoordinate3;
        myAnnotation.title = _nric;
        myAnnotation.subtitle = [NSString        stringWithFormat:@"%i",patientDetails.category];

    }    
    else{
    CLLocationCoordinate2D theCoordinate;
    theCoordinate.longitude = polyclinics1.longtitude;
    NSLog(@"Halo");
    theCoordinate.latitude = polyclinics1.latitude;
    NSLog(@"bye");


    //myAnnotation.pinColor = MKPinAnnotationColorPurple;
    myAnnotation.coordinate = theCoordinate;
    myAnnotation.title = polyclinics1.name;
    myAnnotation.subtitle = [NSString stringWithFormat:@"%i",polyclinics1.telephone];
    }
    [_mapView addAnnotation:myAnnotation];
    [_annotation2 addObject:myAnnotation];

}

Because you have different classes in your array you can't use for (PolyClinics *polyclinics1 in _listOfPolyClinics)to iterate over the array. Use idinstead, then ask the object of what class it is and then cast it to that class if you have to.

Try to change your second for loop to

for (id polyclinics1 in _listOfPolyClinics){
    MyAnnotation* myAnnotation=[[MyAnnotation alloc] init];

    if ([polyclinics1 isKindOfClass:[PatientDetails class]]){ 
        CLLocationCoordinate2D theCoordinate3;
        theCoordinate3.longitude = patientDetails.longitude;
        theCoordinate3.latitude = patientDetails.latitude;

        myAnnotation.coordinate = theCoordinate3;
        myAnnotation.title = _nric;
        myAnnotation.subtitle = [NSString stringWithFormat:@"%i",patientDetails.category];
    } else {
        CLLocationCoordinate2D theCoordinate;
        PolyClinics *polyclinic = (PolyClinics *)polyclinics1;
        theCoordinate.longitude = polyclinic.longtitude;
        NSLog(@"Halo");
        theCoordinate.latitude = polyclinic.latitude;
        NSLog(@"bye");

        //myAnnotation.pinColor = MKPinAnnotationColorPurple;
        myAnnotation.coordinate = theCoordinate;
        myAnnotation.title = polyclinic.name;
        myAnnotation.subtitle = [NSString stringWithFormat:@"%i",polyclinic.telephone];
    }
    [_mapView addAnnotation:myAnnotation];
    [_annotation2 addObject:myAnnotation];
}