MapView显示最多3个注释

Question

really strange problem here.

I add 4 annotations (or 15, or 20, I've tried a lot of times) and I only get 2 or max 3 of them showing on the map (random ones).

here is the source:

//  [self showRealEstates];
    CLLocationCoordinate2D theCoordinate1;
    theCoordinate1.latitude = 37.786996;
    theCoordinate1.longitude = -122.419281;

    CLLocationCoordinate2D theCoordinate2;
    theCoordinate2.latitude = 37.810000;
    theCoordinate2.longitude = -122.477989;

    CLLocationCoordinate2D theCoordinate3;
    theCoordinate3.latitude = 37.760000;
    theCoordinate3.longitude = -122.447989;

    CLLocationCoordinate2D theCoordinate4;
    theCoordinate4.latitude = 37.80000;
    theCoordinate4.longitude = -122.407989;

    MapAnnotationRealEstate* myAnnotation1=[[MapAnnotationRealEstate alloc] initWithCoordinate:theCoordinate1 andTitle:@"Rohan"];

    MapAnnotationRealEstate* myAnnotation2=[[MapAnnotationRealEstate alloc] initWithCoordinate:theCoordinate2 andTitle:@"Vaibhav"];

    MapAnnotationRealEstate* myAnnotation3=[[MapAnnotationRealEstate alloc] initWithCoordinate:theCoordinate3 andTitle:@"Rituraj"];

    MapAnnotationRealEstate* myAnnotation4=[[MapAnnotationRealEstate alloc] initWithCoordinate:theCoordinate4 andTitle:@"Sahil"];

    NSMutableArray * annotations = [[NSMutableArray alloc] init];
    [annotations addObject:myAnnotation1];
    [annotations addObject:myAnnotation2];
    [annotations addObject:myAnnotation3];
    [annotations addObject:myAnnotation4];

    [mapView addAnnotations:annotations];
//  [mapView addAnnotation:myAnnotation1];
//  [mapView addAnnotation:myAnnotation2];
//  [mapView addAnnotation:myAnnotation3];
//  [mapView addAnnotation:myAnnotation4];

    NSLog(@"annotations: %d", [mapView annotations].count);

The log at the end shows 2, or 3. Don't know what to do, simplified the example as much as I could to eliminate other factors, still getting this.

Answer 1

As We can see the lat/long of these two are pretty close. I believe all the annotations are plotted on map and you are just not able to see from the current zoomlevel.

CLLocationCoordinate2D theCoordinate1;
theCoordinate1.latitude = 37.786996;
theCoordinate1.longitude = -122.419281;

CLLocationCoordinate2D theCoordinate4;
theCoordinate4.latitude = 37.80000;
theCoordinate4.longitude = -122.407989;

They seems to be overlapped in mapview in zoomed out view. Try zoom-in your map to max level & I believe you will see all 4 annotations.

or you can try by changing the lat/long of one of these annotations.