From 0d668bf8d3aeb54444bceb5aedc775c584aa3221 Mon Sep 17 00:00:00 2001
From: 0day2010 <0day.zh@gmail.com>
Date: Thu, 15 Aug 2013 14:02:11 +0800
Subject: [PATCH] ADD zoomLevel get method.

---
 MKMapView+ZoomLevel.h | 6 ++++--
 MKMapView+ZoomLevel.m | 8 ++++++--
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/MKMapView+ZoomLevel.h b/MKMapView+ZoomLevel.h
index c6e485f..b8b27cc 100644
--- a/MKMapView+ZoomLevel.h
+++ b/MKMapView+ZoomLevel.h
@@ -4,7 +4,9 @@
 @interface MKMapView (ZoomLevel)
 
 - (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
-    zoomLevel:(NSUInteger)zoomLevel
-    animated:(BOOL)animated;
+                  zoomLevel:(NSUInteger)zoomLevel
+                   animated:(BOOL)animated;
+
+- (int)zoomLevel;
 
 @end
diff --git a/MKMapView+ZoomLevel.m b/MKMapView+ZoomLevel.m
index 2aa42a0..0eb3779 100644
--- a/MKMapView+ZoomLevel.m
+++ b/MKMapView+ZoomLevel.m
@@ -33,8 +33,8 @@ - (double)pixelSpaceYToLatitude:(double)pixelY
 #pragma mark Helper methods
 
 - (MKCoordinateSpan)coordinateSpanWithMapView:(MKMapView *)mapView
-    centerCoordinate:(CLLocationCoordinate2D)centerCoordinate
-    andZoomLevel:(NSUInteger)zoomLevel
+                             centerCoordinate:(CLLocationCoordinate2D)centerCoordinate
+                                 andZoomLevel:(NSUInteger)zoomLevel
 {
     // convert center coordiate to pixel space
     double centerPixelX = [self longitudeToPixelSpaceX:centerCoordinate.longitude];
@@ -86,4 +86,8 @@ - (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
     [self setRegion:region animated:animated];
 }
 
+- (int)zoomLevel {
+    return (21 - round(log2(self.region.span.longitudeDelta * MERCATOR_RADIUS * M_PI / (180.0 * self.bounds.size.width))));
+}
+
 @end