Question

我有一个CLLocation点（lat / long），我想知道它是否在一个确定的MKCoordinateRegion中。我想知道以前在哪个区域是CLLocation点。

感谢。

我找到了解决方案。

MKCoordinateRegion region = self.mapView.region;

CLLocationCoordinate2D location = user.gpsposition.coordinate;
CLLocationCoordinate2D center   = region.center;
CLLocationCoordinate2D northWestCorner, southEastCorner;

northWestCorner.latitude  = center.latitude  - (region.span.latitudeDelta  / 2.0);
northWestCorner.longitude = center.longitude - (region.span.longitudeDelta / 2.0);
southEastCorner.latitude  = center.latitude  + (region.span.latitudeDelta  / 2.0);
southEastCorner.longitude = center.longitude + (region.span.longitudeDelta / 2.0);

if (
    location.latitude  >= northWestCorner.latitude && 
    location.latitude  <= southEastCorner.latitude &&

    location.longitude >= northWestCorner.longitude && 
    location.longitude <= southEastCorner.longitude
    )
{
    // User location (location) in the region - OK :-)
    NSLog(@"Center (%f, %f) span (%f, %f) user: (%f, %f)| IN!", region.center.latitude, region.center.longitude, region.span.latitudeDelta, region.span.longitudeDelta, location.latitude, location.longitude);

}else {

    // User location (location) out of the region - NOT ok :-(
    NSLog(@"Center (%f, %f) span (%f, %f) user: (%f, %f)| OUT!", region.center.latitude, region.center.longitude, region.span.latitudeDelta, region.span.longitudeDelta, location.latitude, location.longitude);
}

Answer 1

有类似的问题。答案正确 - How to check if MKCoordinateRegion contains CLLocationCoordinate2D without using MKMapView?

祝你好运：）

Answer 2

这似乎是正确但倒退。区域西北角的纬度将大于中心，因为当您向北移动时纬度会增加。经度是正确的。因此这里计算的角落是切换的，西北角的卡纳实际上是西南角，而东南角则是东北角。但代码有效，因为if语句也是向后的。它应该更像是

CLLocationCoordinate2D newMapCenter = self.mapView.centerCoordinate;
CLLocationCoordinate2D startingCenter = self.startingRegion.center;
CLLocationCoordinate2D northWestCorner, southEastCorner;

northWestCorner.latitude = startingCenter.latitude + (self.startingRegion.span.latitudeDelta / 2.0);
northWestCorner.longitude = startingCenter.longitude - (self.startingRegion.span.longitudeDelta / 2.0);
southEastCorner.latitude = startingCenter.latitude - (self.startingRegion.span.latitudeDelta / 2.0);
southEastCorner.longitude = startingCenter.longitude + (self.startingRegion.span.longitudeDelta / 2.0);

if (newMapCenter.latitude <= northWestCorner.latitude && newMapCenter.latitude >= southEastCorner.latitude && newMapCenter.longitude >= northWestCorner.longitude && newMapCenter.longitude <= southEastCorner.longitude) {
    // still in original region
    NSLog(@"same region");
}
else
{
    // new region
    NSLog(@"new region");
}

所以答案是正确的，但也是错误的。但它有效，所以我猜它更正确。

可以知道CLLocation点是否在MKCoordinateRegion中？

2 个答案: