ios - determine current zoomscale for mapview -

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how can calculate current zoomscale mkmapview?

use following code:

#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; }

the return value of getzoomlevel method current zoom level of mapview property.


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