Add `overlays` property to `MGLMapView.mm`

Implemented by filtering the `annotations` property for
annotations that conform to `MGLOverlay` protocol.

2 files changed, 14 insertions, 0 deletions

diff --git a/platform/macos/src/MGLMapView.h b/platform/macos/src/MGLMapView.h
index fb715a506d..eb37f0540d 100644
--- a/platform/macos/src/MGLMapView.h
+++ b/platform/macos/src/MGLMapView.h
@@ -729,6 +729,8 @@ MGL_EXPORT IB_DESIGNABLE
 
 #pragma mark Overlaying the Map
 
+@property (nonatomic, readonly, nullable) NS_ARRAY_OF(id <MGLOverlay>) *overlays;
+
 /**
  Adds a single overlay to the map.
 
diff --git a/platform/macos/src/MGLMapView.mm b/platform/macos/src/MGLMapView.mm
index 59951f946d..db459f6a2f 100644
--- a/platform/macos/src/MGLMapView.mm
+++ b/platform/macos/src/MGLMapView.mm
@@ -2413,6 +2413,18 @@ public:
 
 #pragma mark Overlays
 
+- (nullable NS_ARRAY_OF(id <MGLOverlay>) *)overlays {
+    NS_MUTABLE_ARRAY_OF(id <MGLOverlay>) *mutableOverlays = [NSMutableArray new];
+
+    [self.annotations enumerateObjectsUsingBlock:^(id<MGLAnnotation>  _Nonnull annotation, NSUInteger idx, BOOL * _Nonnull stop) {
+        if ([annotation conformsToProtocol:@protocol(MGLOverlay)]) {
+            [mutableOverlays addObject:(id<MGLOverlay>)annotation];
+        }
+    }];
+
+    return [NSArray arrayWithArray:mutableOverlays];
+}
+
 - (void)addOverlay:(id <MGLOverlay>)overlay {
     [self addOverlays:@[overlay]];
 }