[MDCBottomNavigationBar] Add checks for nil when a new appearance is set and provide defaults. Based on failures observed in testing when removing deprecated badge properties, these values are nil by neglect and not nil by intent. Hence we will provide default values for badge appearance properties when they are nil and set on the nav bar.

PiperOrigin-RevId: 719333484

Author: loading-google

components/Badges/tests/unit/MDCBadgeViewTests.m

@@ -17,8 +17,10 @@
 
 #import "MDCBadgeView.h"
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface MDCBadgeViewTests : XCTestCase
-@property(nonatomic, strong) MDCBadgeView *badge;
+@property(nonatomic, strong, nullable) MDCBadgeView *badge;
 @end
 
 @implementation MDCBadgeViewTests
@@ -109,3 +111,5 @@ - (void)testLayoutSubviewsWontAdjustFrame {
 }
 
 @end
+
+NS_ASSUME_NONNULL_END

components/BottomNavigation/src/MDCBottomNavigationBar.h

@@ -127,6 +127,10 @@ typedef NS_ENUM(NSInteger, MDCBottomNavigationBarAlignment) {
  An array of MDCBottomNavigationBarItems that is used to populate bottom navigation bar content. It
  is strongly recommended the array contain at least three items and no more than five items --
  appearance may degrade outside of this range.
+
+ If a given item has no badge appearance set, then the itemBadgeAppearance is used.
+ Additionally, if a given badge appearance has a `nil` for its textColor and/or font, then the
+ values from the itemBadgeAppearance are used.
  */
 @property(nonatomic, copy, nonnull) NSArray<MDCBottomNavigationBarItem *> *barItems;
 
@@ -350,6 +354,10 @@ traitCollectionDidChange:. The block is called after the call to the superclass.
  If a given UITabBarItem has set a non-nil badgeColor, then that value will be used for that item
  view's badge instead of the backgroundColor associated with this appearance object.
 
+ If a given badge appearance has set a `nil` textColor, then the default `whiteColor` will be used.
+ If a given badge appearance has set a `nil` font, then the default `systemFontOfSize:8` will be
+ used.
+
  Note that the individual itemBadge* properties will be deprecated and already act as proxies for
  modifying the itemBadgeAppearance of each badge directly.
  */

components/BottomNavigation/src/MDCBottomNavigationBar.m

@@ -824,6 +824,16 @@ - (void)updateBarItems {
     itemView.selectionIndicatorColor = self.selectionIndicatorColor;
     itemView.selectionIndicatorSize = self.selectionIndicatorSize;
     [self configureTitleStateForItemView:itemView];
+
+    // If a given badge appearance has a `nil` for its textColor and font, then the values from the
+    // itemBadgeAppearance are used.
+    if (!self.barItems[i].badgeAppearance.textColor) {
+      self.barItems[i].badgeAppearance.textColor = _itemBadgeAppearance.textColor;
+    }
+    if (!self.barItems[i].badgeAppearance.font) {
+      self.barItems[i].badgeAppearance.font = _itemBadgeAppearance.font;
+    }
+
     [self configureItemView:itemView
                    withItem:self.barItems[i].item
                  appearance:self.barItems[i].badgeAppearance];
@@ -1279,6 +1289,16 @@ - (void)setRippleColor:(nullable UIColor *)rippleColor {
 - (void)setItemBadgeAppearance:(MDCBadgeAppearance *)itemBadgeAppearance {
   _itemBadgeAppearance = [itemBadgeAppearance copy];
 
+  // Setting default values if `nil` is received for the appearance properties.
+  // The default value for the textColor is `white` and the default value for the font is
+  // `systemFontOfSize:8`.
+  if (!_itemBadgeAppearance.textColor) {
+    _itemBadgeAppearance.textColor = [UIColor whiteColor];
+  }
+  if (!_itemBadgeAppearance.font) {
+    _itemBadgeAppearance.font = [UIFont systemFontOfSize:kBadgeFontSize];
+  }
+
   for (NSUInteger i = 0; i < [self itemCount]; ++i) {
     MDCBottomNavigationItemView *itemView = self.itemViews[i];
     if (self.barItems.count > 0 && self.barItems[i].badgeAppearance != nil) {

components/BottomNavigation/tests/snapshot/MDCBottomNavigationBarSnapshotTests.m

@@ -475,26 +475,25 @@ - (void)testCustomBadgeColorsOverrideDefaultBadgeAppearanceWhenSetBeforeBarItems
   [self generateAndVerifySnapshot];
 }
 
-- (void)testClearBadgeColorsRendersClearBackgroundAndUILabelDefaultTextColor {
+- (void)testClearBadgeColorRendersClearBackgroundAndDefaultFont {
   // Given
   self.tabItem1.badgeValue = @"";
   self.tabItem2.badgeValue = @"Black on Clear";
-  self.tabItem3.badgeValue = @"Black on Green";
   self.navigationBar.frame = CGRectMake(0, 0, MDCBottomNavigationBarTestWidthiPad,
                                         MDCBottomNavigationBarTestHeightTypical);
 
   // When
-  MDCBadgeAppearance *greenAppearance = [[MDCBadgeAppearance alloc] init];
-  greenAppearance.font = [UIFont systemFontOfSize:8.0];
-  greenAppearance.backgroundColor = UIColor.greenColor;
-  greenAppearance.textColor = UIColor.blackColor;
+  MDCBadgeAppearance *normalAppearance = [[MDCBadgeAppearance alloc] init];
+  normalAppearance.font = nil;
+  normalAppearance.backgroundColor = UIColor.clearColor;
+  normalAppearance.textColor = UIColor.blackColor;
   MDCBottomNavigationBarItem *barItem1 =
       [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem1];
   MDCBottomNavigationBarItem *barItem2 =
-      [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem2];
+      [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem2
+                                          badgeAppearance:normalAppearance];
   MDCBottomNavigationBarItem *barItem3 =
-      [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem3
-                                          badgeAppearance:greenAppearance];
+      [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem3];
   MDCBottomNavigationBarItem *barItem4 =
       [[MDCBottomNavigationBarItem alloc] initWithBarItem:self.tabItem4];
   MDCBottomNavigationBarItem *barItem5 =
@@ -510,10 +509,10 @@ - (void)testClearBadgeColorsRendersClearBackgroundAndUILabelDefaultTextColor {
   [self generateAndVerifySnapshot];
 }
 
-- (void)testNilBadgeColorsRendersTintBackgroundAndUILabelDefaultTextColor {
+- (void)testNilBadgeColorsRendersTintBackgroundAndNavigationBarDefaultTextColor {
   // Given
   self.tabItem1.badgeValue = @"";
-  self.tabItem2.badgeValue = @"Black on Tint Color";
+  self.tabItem2.badgeValue = @"White on Tint Color";
   self.tabItem3.badgeValue = @"Black on Green";
   self.navigationBar.frame = CGRectMake(0, 0, MDCBottomNavigationBarTestWidthiPad,
                                         MDCBottomNavigationBarTestHeightTypical);
@@ -545,6 +544,24 @@ - (void)testNilBadgeColorsRendersTintBackgroundAndUILabelDefaultTextColor {
   [self generateAndVerifySnapshot];
 }
 
+- (void)testDefaultBadgeTextFont {
+  // Given
+  self.tabItem1.badgeValue = @"";
+  self.tabItem2.badgeValue = @"10";
+  self.navigationBar.frame = CGRectMake(0, 0, MDCBottomNavigationBarTestWidthTypical,
+                                        MDCBottomNavigationBarTestHeightTypical);
+
+  // When
+  MDCBadgeAppearance *badgeAppearance = [[MDCBadgeAppearance alloc] init];
+  badgeAppearance.font = nil;
+  self.navigationBar.itemBadgeAppearance = badgeAppearance;
+  self.navigationBar.items =
+      @[ self.tabItem1, self.tabItem2, self.tabItem3, self.tabItem4, self.tabItem5 ];
+
+  // Then
+  [self generateAndVerifySnapshot];
+}
+
 - (void)testCustomBadgeTextFontSetBeforeItems {
   // Given
   self.tabItem1.badgeValue = @"";
@@ -563,7 +580,7 @@ - (void)testCustomBadgeTextFontSetBeforeItems {
   [self generateAndVerifySnapshot];
 }
 
-- (void)testCustomBadgeTextFontSetAfterItems {
+- (void)testCustomBadgeTextFontSetAfterItemsUsesDefaultBadgeColor {
   // Given
   self.tabItem1.badgeValue = @"";
   self.tabItem2.badgeValue = @"10";