我有幾個要添加到我的MKMapView的注釋（它可以是0-n個項目，其中n通常約為5）。我可以很好地添加注釋，但是我想立即調整地圖的大小以適合屏幕上的所有注釋，而且我不確定該怎么做。我一直在看，-regionThatFits:但是我不確定該怎么做。我將發(fā)布一些代碼以顯示到目前為止的內容。我認為這應該是一項通常很簡單的任務，但到目前為止，我對MapKit感到有些不知所措。- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{location = newLocation.coordinate;//One location is obtained.. just zoom to that locationMKCoordinateRegion region;region.center = location;//Set Zoom level using SpanMKCoordinateSpan span;span.latitudeDelta = 0.015;span.longitudeDelta = 0.015;region.span = span;// Set the region here... but I want this to be a dynamic size// Obviously this should be set after I've added my annotations[mapView setRegion:region animated:YES];// Test data, using these as annotations for nowNSArray *arr = [NSArray arrayWithObjects:@"one", @"two", @"three", @"four", nil];float ex = 0.01;for (NSString *s in arr) {    JBAnnotation *placemark = [[JBAnnotation alloc] initWithLat:(location.latitude + ex) lon:location.longitude];    [mapView addAnnotation:placemark];    ex = ex + 0.005;}    // What do I do here?    [mapView setRegion:[mapView regionThatFits:region] animated:YES];}請注意，這一切都是在我收到位置更新信息時發(fā)生的...我不知道這是否合適。如果沒有，哪里會有更好的地方？-viewDidLoad？提前致謝。