ios - calling a method with parameters -

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i`m using mapkit framework , want ask :

+ (nsuinteger)zoomlevelformaprect:(mkmaprect)mrect withmapviewsizeinpixels:(cgsize)viewsizeinpixels {     nsuinteger zoomlevel = maximum_zoom; // maximum_zoom 20 mapkit     mkzoomscale zoomscale = mrect.size.width / viewsizeinpixels.width; //mkzoomscale cgfloat typedef     double zoomexponent = log2(zoomscale);     zoomlevel = (nsuinteger)(maximum_zoom - ceil(zoomexponent));     return zoomlevel; }

this method..how can know value of mrect , viewsizeinpixels parameters able call it?? thx in advance :)

the map view's current mkmaprect visiblemaprect property , view size in frame.size (since mkmapview subclass of uiview) method called using like:

nsuinteger zoomlevel = [utilityclass                             zoomlevelformaprect:mapview.visiblemaprect                             withmapviewsizeinpixels:mapview.frame.size];

utilityclass whatever class method in , replace mapview whatever map view named.

by way, mapkit framework reference , location awareness programming guide worth looking at.


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