[Tabs] Implementing TabBar Typography Themer. (#3278)

* Implementing TabBar Typography Themer.

* add typographyScheme to a tabbar example.

* couple of nits.

MaterialComponents.podspec

@@ -606,6 +606,14 @@ end
       extension.dependency "MaterialComponents/Tabs"
       extension.dependency "MaterialComponents/Themes"
     end
+    component.subspec "TypographyThemer" do |extension|
+      extension.ios.deployment_target = '8.0'
+      extension.public_header_files = "components/Tabs/src/#{extension.base_name}/*.h"
+      extension.source_files = "components/Tabs/src/#{extension.base_name}/*.{h,m}"
+
+      extension.dependency "MaterialComponents/Tabs"
+      extension.dependency "MaterialComponents/schemes/Typography"
+    end
 
   end
 

components/Tabs/BUILD

@@ -78,6 +78,21 @@ mdc_objc_library(
     visibility = ["//visibility:public"],
 )
 
+mdc_objc_library(
+    name = "TypographyThemer",
+    srcs = native.glob(["src/TypographyThemer/*.m"]),
+    hdrs = native.glob(["src/TypographyThemer/*.h"]),
+    includes = ["src/TypographyThemer"],
+    sdk_frameworks = [
+        "UIKit",
+    ],
+    deps = [
+        ":Tabs",
+        "//components/schemes/Typography",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 mdc_objc_library(
     name = "private",
     hdrs = native.glob(["src/private/*.h"]),
@@ -100,6 +115,7 @@ mdc_objc_library(
         ":Tabs",
         ":ColorThemer",
         ":FontThemer",
+        ":TypographyThemer",
         ":private",
     ],
     visibility = ["//visibility:private"],

components/Tabs/examples/supplemental/TabBarIconExampleSupplemental.m

@@ -21,6 +21,7 @@
 #import "TabBarIconExampleSupplemental.h"
 
 #import "MaterialPalettes.h"
+#import "MDCTabBarTypographyThemer.h"
 
 // Exposing selectors defined in the main example class
 @interface TabBarIconExample ()
@@ -37,6 +38,9 @@ - (void)setupExampleViews {
   [self setupScrollingContent];
 
   [self setupAlignmentButton];
+
+  MDCTypographyScheme *typographyScheme = [[MDCTypographyScheme alloc] init];
+  [MDCTabBarTypographyThemer applyTypographyScheme:typographyScheme toTabBar:self.tabBar];
 }
 
 - (void)setupAlignmentButton {

components/Tabs/src/FontThemer/MDCTabBarFontThemer.h

@@ -19,6 +19,7 @@ limitations under the License.
 
 /**
  Used to apply a font scheme to theme MDCTabBar.
+ This Class will be deprecated soon please use MDCTabBarTypographyThemer instead.
  */
 @interface MDCTabBarFontThemer : NSObject
 

components/Tabs/src/TypographyThemer/MDCTabBarTypographyThemer.h

@@ -0,0 +1,34 @@
+/*
+Copyright 2018-present the Material Components for iOS authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#import "MaterialTabs.h"
+#import "MaterialTypographyScheme.h"
+
+/**
+ Used to apply a typography scheme to theme MDCTabBar.
+ */
+@interface MDCTabBarTypographyThemer : NSObject
+
+/**
+ Applies a typography scheme to theme a MDCTabBar.
+
+ @param typographyScheme The typography scheme to apply to MDCTabBar.
+ @param tabBar A MDCTabBar instance to apply a color scheme.
+ */
++ (void)applyTypographyScheme:(nonnull id<MDCTypographyScheming>)typographyScheme
+                     toTabBar:(nonnull MDCTabBar *)tabBar;
+
+@end

components/Tabs/src/TypographyThemer/MDCTabBarTypographyThemer.m

@@ -0,0 +1,27 @@
+/*
+ Copyright 2018-present the Material Components for iOS authors. All Rights Reserved.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "MDCTabBarTypographyThemer.h"
+
+@implementation MDCTabBarTypographyThemer
+
++ (void)applyTypographyScheme:(nonnull id<MDCTypographyScheming>)typographyScheme
+                     toTabBar:(nonnull MDCTabBar *)tabBar {
+  tabBar.selectedItemTitleFont = typographyScheme.button;
+  tabBar.unselectedItemTitleFont = typographyScheme.button;
+}
+
+@end

components/Tabs/tests/unit/MDCTabBarTypographyThemerTests.m

@@ -0,0 +1,36 @@
+/*
+ Copyright 2018-present the Material Components for iOS authors. All Rights Reserved.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "MaterialTabs.h"
+#import "MDCTabBarTypographyThemer.h"
+
+#import <XCTest/XCTest.h>
+
+@interface MDCTabBarTypographyThemerTests : XCTestCase
+
+@end
+
+@implementation MDCTabBarTypographyThemerTests
+
+- (void)testTabBarFontThemerApplyFontSchemeProperly {
+  MDCTypographyScheme *typographyScheme = [[MDCTypographyScheme alloc] init];
+  MDCTabBar *tabBar = [[MDCTabBar alloc] init];
+  [MDCTabBarTypographyThemer applyTypographyScheme:typographyScheme toTabBar:tabBar];
+  XCTAssertEqualObjects(tabBar.selectedItemTitleFont, typographyScheme.button);
+  XCTAssertEqualObjects(tabBar.unselectedItemTitleFont, typographyScheme.button);
+}
+
+@end