Add theme change handler (#89)

Sources/DarkModeCore/DMEnvironmentConfiguration.h

@@ -10,6 +10,7 @@ NS_ASSUME_NONNULL_BEGIN
 @interface DMEnvironmentConfiguration : NSObject
 
 @property (nonatomic) BOOL useImageAsset; // Defaults to NO
+@property (nullable, nonatomic) void (^themeChangeHandler)(void); // Defaults to nil
 
 - (instancetype)init;
 

Sources/DarkModeCore/DMEnvironmentConfiguration.m

@@ -11,6 +11,7 @@
   self = [super init];
   if (self) {
     _useImageAsset = NO;
+    _themeChangeHandler = nil;
   }
   return self;
 }

Sources/DarkModeCore/DMTraitCollection.h

@@ -51,10 +51,4 @@ typedef NS_ENUM(NSInteger, DMUserInterfaceStyle) {
 
 @end
 
-@interface NSObject (DMTraitEnvironment)
-
-+ (void)swizzleTraitCollectionDidChangeToDMTraitCollectionDidChange API_AVAILABLE(ios(13.0));
-
-@end
-
 NS_ASSUME_NONNULL_END

Sources/DarkModeCore/DMTraitCollection.m

@@ -10,6 +10,12 @@
 
 @import ObjectiveC;
 
+@interface NSObject (DMTraitEnvironment)
+
++ (void)swizzleTraitCollectionDidChangeToDMTraitCollectionDidChange API_AVAILABLE(ios(13.0));
+
+@end
+
 @implementation NSObject (DMTraitEnvironment)
 
 + (void)swizzleTraitCollectionDidChangeToDMTraitCollectionDidChange {
@@ -49,6 +55,7 @@
 
 static DMTraitCollection *_overrideTraitCollection = nil; // This is set manually in setOverrideTraitCollection:animated
 static void (^_userInterfaceStyleChangeHandler)(DMTraitCollection *, BOOL) = nil;
+static void (^_themeChangeHandler)(void) = nil;
 static BOOL _isObservingNewWindowAddNotification = NO;
 
 + (DMTraitCollection *)currentTraitCollection {
@@ -195,6 +202,9 @@ static BOOL _isObservingNewWindowAddNotification = NO;
       return;
 
     [weakSelf updateUIWithViews:strongApp.windows viewControllers:nil traitCollection:traitCollection animated:animated];
+
+    if (_themeChangeHandler)
+      _themeChangeHandler();
   };
 
   [self observeNewWindowNotificationIfNeeded];
@@ -212,6 +222,9 @@ static BOOL _isObservingNewWindowAddNotification = NO;
       return;
 
     [weakSelf updateUIWithViews:nil viewControllers:[NSArray arrayWithObject:strongVc] traitCollection:traitCollection animated:animated];
+
+    if (_themeChangeHandler)
+      _themeChangeHandler();
   };
 
   if (syncImmediately)
@@ -275,6 +288,8 @@ static BOOL _isObservingNewWindowAddNotification = NO;
       [UIView dm_swizzleSetBackgroundColor];
       [UIImage dm_swizzleIsEqual];
     }
+
+    _themeChangeHandler = configuration.themeChangeHandler;
   });
 }
 

Sources/DarkModeCore/include/DarkModeCore.h

@@ -4,7 +4,7 @@
 
 #import "../DMDynamicColor.h"
 #import "../DMDynamicImage.h"
-#import "../DMEnvironmentConfiguration"
+#import "../DMEnvironmentConfiguration.h"
 #import "../DMNamespace.h"
 #import "../DMTraitCollection.h"
 #import "../UIColor+DarkModeKit.h"

Sources/FluentDarkModeKit/DarkModeManager.swift

@@ -11,21 +11,24 @@ import UIKit
 public final class DarkModeManager: NSObject {
   private static var swizzlingConfigured = false
 
-  public class func register(with configuration: DMEnvironmentConfiguration, for application: UIApplication, syncImmediately: Bool = false, animated: Bool = false) {
+  public static func setup(with configuration: DMEnvironmentConfiguration) {
     commonSetup(with: configuration)
+  }
+
+  public static func register(with application: UIApplication, syncImmediately: Bool = false, animated: Bool = false) {
     DMTraitCollection.register(with: application, syncImmediately: syncImmediately, animated: animated)
   }
 
-  public class func register(with configuration: DMEnvironmentConfiguration, for viewController: UIViewController, syncImmediately: Bool = false, animated: Bool = false) {
-    commonSetup(with: configuration)
+  @available(iOSApplicationExtension 11.0, *)
+  public static func register(with viewController: UIViewController, syncImmediately: Bool = false, animated: Bool = false) {
     DMTraitCollection.register(with: viewController, syncImmediately: syncImmediately, animated: animated)
   }
 
-  public class func unregister() {
+  public static func unregister() {
     DMTraitCollection.unregister()
   }
 
-  private class func commonSetup(with configuration: DMEnvironmentConfiguration) {
+  private static func commonSetup(with configuration: DMEnvironmentConfiguration) {
     guard !swizzlingConfigured else {
       return
     }

Sources/FluentDarkModeKitExample/AppDelegate.swift

@@ -16,7 +16,11 @@ final class AppDelegate: UIResponder, UIApplicationDelegate {
   ) -> Bool {
 
     let configuration = DMEnvironmentConfiguration()
-    DarkModeManager.register(with: configuration, for: application)
+    configuration.themeChangeHandler = {
+      print("theme changed")
+    }
+    DarkModeManager.setup(with: configuration)
+    DarkModeManager.register(with: application)
 
     if #available(iOS 13.0, *) {
       return true

Tests/FluentDarkModeKitTests/DarkModeKitTests.swift

@@ -9,7 +9,8 @@ import XCTest
 final class DarkModeKitTests: XCTestCase {
   func testSetBackgroundColorSwizzling() {
     UIWindow.appearance().backgroundColor = .white
-    DarkModeManager.register(with: DMEnvironmentConfiguration(), for: .shared)
+    DarkModeManager.setup(with: DMEnvironmentConfiguration())
+    DarkModeManager.register(with: .shared)
     _ = UIWindow()
   }