如何计算MKMapView的当前zoomScale?
最佳答案
使用以下代码:
#define MERCATOR_RADIUS 85445659.44705395
#define MAX_GOOGLE_LEVELS 20
- (double)getZoomLevel {
CLLocationDegrees longitudeDelta = self.mapView.region.span.longitudeDelta;
CGFloat mapWidthInPixels = self.mapView.bounds.size.width;
double zoomScale = longitudeDelta * MERCATOR_RADIUS * M_PI / (180.0 * mapWidthInPixels);
double zoomer = MAX_GOOGLE_LEVELS - log2( zoomScale );
if ( zoomer < 0 ) zoomer = 0;
// zoomer = round(zoomer);
return zoomer;
}
getZoomLevel
方法的返回值将是mapView
属性的当前缩放级别。关于ios - 确定 map View 的当前缩放比例,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/5966683/