iphone - MapView regionThatFits 使用 Horizo​​ntalAccuracy 设置

Question

我正在寻找一种将米转换为地图视图区域的方法。

CLLocation'shorizontalAccuracy是双精度数，以米为单位表示精度。regionThatFits:需要MKCoordinateRegion一个spanwithlongitudeDelta和latitudeDelta。如何将米转换为经度/纬度跨度？

Answer 1

找到了答案。好像纬度1度等于111公里左右，也就是111120米

- (MKCoordinateRegion)regionForAccuracyOfLocation:(CLLocation *)location
{
    CLLocationDegrees spanInDegrees = (CLLocationDegrees) (location.horizontalAccuracy / 222240);

    MKCoordinateSpan span = MKCoordinateSpanMake(spanInDegrees, spanInDegrees) ;
    CLLocationCoordinate2D coordinate = location.coordinate;
    MKCoordinateRegion region = MKCoordinateRegionMake(coordinate, span);

    return region;
}