[ios] Fix bug where scale bar shows 0 mm instead of 0 (#15381)

1 files changed, 13 insertions, 2 deletions

diff --git a/platform/ios/src/MGLScaleBar.mm b/platform/ios/src/MGLScaleBar.mm
index 9590a99438..993852d8b9 100644
--- a/platform/ios/src/MGLScaleBar.mm
+++ b/platform/ios/src/MGLScaleBar.mm
@@ -84,7 +84,7 @@ static const MGLRow MGLImperialTable[] ={
 @property (nonatomic) UIColor *secondaryColor;
 @property (nonatomic) CALayer *borderLayer;
 @property (nonatomic, assign) CGFloat borderWidth;
-@property (nonatomic) NSCache* labelImageCache;
+@property (nonatomic) NSMutableDictionary* labelImageCache;
 @property (nonatomic) MGLScaleBarLabel* prototypeLabel;
 @property (nonatomic) CGFloat lastLabelWidth;
 
@@ -159,7 +159,7 @@ static const CGFloat MGLFeetPerMeter = 3.28084;
     _formatter = [[MGLDistanceFormatter alloc] init];
 
     // Image labels are now images
-    _labelImageCache              = [[NSCache alloc] init];
+    _labelImageCache              = [[NSMutableDictionary alloc] init];
     _prototypeLabel               = [[MGLScaleBarLabel alloc] init];
     _prototypeLabel.font          = [UIFont systemFontOfSize:8 weight:UIFontWeightMedium];
     _prototypeLabel.clipsToBounds = NO;
@@ -180,6 +180,17 @@ static const CGFloat MGLFeetPerMeter = 3.28084;
 
     // Zero is a special case (no formatting)
     [self addZeroLabel];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resetLabelImageCache) name:NSCurrentLocaleDidChangeNotification object:nil];
+}
+
+- (void)dealloc {
+    [[NSNotificationCenter defaultCenter] removeObserver:self];
+}
+
+- (void)resetLabelImageCache {
+    self.labelImageCache = [[NSMutableDictionary alloc] init];
+    [self addZeroLabel];
 }
 
 #pragma mark - Dimensions