使用前先引入 #import <MapKit/MapKit.h>
MKMapView * mapView = [[MKMapView alloc] initWithFrame:self.view.bounds];
mapView.mapType = MKMapTypeStandard;
[mapView setZoomEnabled:YES];
[mapView setScrollEnabled:YES];
//显示用户当前的坐标
mapView.showsUserLocation = YES;
//1.先定义区域的中心点
CLLocationCoordinate2D coordinate = CLLocationCoordinate2DMake(28.2148, 112.893);
//2.定义显示的范围（范围越小，地图越精确）
MKCoordinateSpan span = MKCoordinateSpanMake(0.1, 0.1);
//3.定义一个显示区域
MKCoordinateRegion region = MKCoordinateRegionMake(coordinate, span);
[mapView setRegion:region animated:YES];
