Added support of lineDashPattern polyline prop to iOS Google Maps (react-native-maps#2243)

Author: satori-ytolstoguzov

lib/ios/AirGoogleMaps/AIRGoogleMapPolyline.h

@@ -21,6 +21,7 @@
 @property (nonatomic, strong) UIColor *strokeColor;
 @property (nonatomic, assign) double strokeWidth;
 @property (nonatomic, assign) UIColor *fillColor;
+@property (nonatomic, strong) NSArray<NSNumber *> *lineDashPattern;
 @property (nonatomic, assign) BOOL geodesic;
 @property (nonatomic, assign) NSString *title;
 @property (nonatomic, assign) int zIndex;

lib/ios/AirGoogleMaps/AIRGoogleMapPolyline.m

@@ -32,13 +32,16 @@ -(void)setCoordinates:(NSArray<AIRMapCoordinate *> *)coordinates
     [path addCoordinate:coordinates[i].coordinate];
   }
 
-   _polyline.path = path;
+  _polyline.path = path;
+
+  [self configureStyleSpansIfNeeded];
 }
 
 -(void)setStrokeColor:(UIColor *)strokeColor
 {
   _strokeColor = strokeColor;
   _polyline.strokeColor = strokeColor;
+  [self configureStyleSpansIfNeeded];
 }
 
 -(void)setStrokeWidth:(double)strokeWidth
@@ -53,6 +56,11 @@ -(void)setFillColor:(UIColor *)fillColor
   _polyline.spans = @[[GMSStyleSpan spanWithColor:fillColor]];
 }
 
+- (void)setLineDashPattern:(NSArray<NSNumber *> *)lineDashPattern {
+  _lineDashPattern = lineDashPattern;
+  [self configureStyleSpansIfNeeded];
+}
+
 -(void)setGeodesic:(BOOL)geodesic
 {
   _geodesic = geodesic;
@@ -81,4 +89,23 @@ - (void)setOnPress:(RCTBubblingEventBlock)onPress {
   _polyline.onPress = onPress;
 }
 
+- (void)configureStyleSpansIfNeeded {
+  if (!_strokeColor || !_lineDashPattern || !_polyline.path) {
+      return;
+  }
+
+  BOOL isLine = YES;
+  NSMutableArray *styles = [[NSMutableArray alloc] init];
+  for (NSInteger i = 0; i < _lineDashPattern.count; i++) {
+    if (isLine) {
+      [styles addObject:[GMSStrokeStyle solidColor:_strokeColor]];
+    } else {
+      [styles addObject:[GMSStrokeStyle solidColor:[UIColor clearColor]]];
+    }
+    isLine = !isLine;
+  }
+
+  _polyline.spans = GMSStyleSpans(_polyline.path, styles, _lineDashPattern, kGMSLengthRhumb);
+}
+
 @end

lib/ios/AirGoogleMaps/AIRGoogleMapPolylineManager.m

@@ -34,6 +34,7 @@ - (UIView *)view
 RCT_EXPORT_VIEW_PROPERTY(fillColor, UIColor)
 RCT_EXPORT_VIEW_PROPERTY(strokeColor, UIColor)
 RCT_EXPORT_VIEW_PROPERTY(strokeWidth, double)
+RCT_EXPORT_VIEW_PROPERTY(lineDashPattern, NSArray)
 RCT_EXPORT_VIEW_PROPERTY(geodesic, BOOL)
 RCT_EXPORT_VIEW_PROPERTY(zIndex, int)
 RCT_EXPORT_VIEW_PROPERTY(tappable, BOOL)