ios 百度地图指定区域_获取百度地图可视区域范围的数据
时间: 2023-08-04 22:08:18 浏览: 121
要获取百度地图可视区域范围的数据,你可以使用以下方法:
1. 获取当前地图的中心点坐标:
```
CLLocationCoordinate2D centerCoordinate = mapView.centerCoordinate;
```
2. 获取当前地图的缩放级别:
```
float zoomLevel = mapView.zoomLevel;
```
3. 计算出当前地图可视区域的四个顶点坐标:
```
BMKCoordinateRegion region = BMKCoordinateRegionMakeWithDistance(centerCoordinate, 1000 * pow(2, (21 - zoomLevel)), 1000 * pow(2, (21 - zoomLevel)));
CLLocationCoordinate2D topLeftCoordinate = CLLocationCoordinate2DMake(centerCoordinate.latitude + region.span.latitudeDelta / 2.0, centerCoordinate.longitude - region.span.longitudeDelta / 2.0);
CLLocationCoordinate2D bottomLeftCoordinate = CLLocationCoordinate2DMake(centerCoordinate.latitude - region.span.latitudeDelta / 2.0, centerCoordinate.longitude - region.span.longitudeDelta / 2.0);
CLLocationCoordinate2D topRightCoordinate = CLLocationCoordinate2DMake(centerCoordinate.latitude + region.span.latitudeDelta / 2.0, centerCoordinate.longitude + region.span.longitudeDelta / 2.0);
CLLocationCoordinate2D bottomRightCoordinate = CLLocationCoordinate2DMake(centerCoordinate.latitude - region.span.latitudeDelta / 2.0, centerCoordinate.longitude + region.span.longitudeDelta / 2.0);
```
4. 将四个顶点坐标转换成百度地图的墨卡托坐标:
```
BMKMapPoint topLeftPoint = BMKMapPointForCoordinate(topLeftCoordinate);
BMKMapPoint bottomLeftPoint = BMKMapPointForCoordinate(bottomLeftCoordinate);
BMKMapPoint topRightPoint = BMKMapPointForCoordinate(topRightCoordinate);
BMKMapPoint bottomRightPoint = BMKMapPointForCoordinate(bottomRightCoordinate);
```
5. 计算出当前地图可视区域在百度地图中的矩形区域:
```
BMKMapRect visibleRect = BMKMapRectMake(fmin(topLeftPoint.x, bottomLeftPoint.x), fmin(topLeftPoint.y, topRightPoint.y), fabs(topLeftPoint.x - topRightPoint.x), fabs(topLeftPoint.y - bottomLeftPoint.y));
```
6. 将矩形区域转换成经纬度坐标范围:
```
BMKCoordinateRegion visibleRegion = BMKCoordinateRegionForMapRect(visibleRect);
CLLocationCoordinate2D visibleTopLeftCoordinate = visibleRegion.center;
visibleTopLeftCoordinate.latitude += visibleRegion.span.latitudeDelta / 2.0;
visibleTopLeftCoordinate.longitude -= visibleRegion.span.longitudeDelta / 2.0;
CLLocationCoordinate2D visibleBottomRightCoordinate = visibleRegion.center;
visibleBottomRightCoordinate.latitude -= visibleRegion.span.latitudeDelta / 2.0;
visibleBottomRightCoordinate.longitude += visibleRegion.span.longitudeDelta / 2.0;
```
最终,`visibleTopLeftCoordinate` 和 `visibleBottomRightCoordinate` 就是当前地图可视区域的经纬度坐标范围。