iOS使用觀察者模式實現推送消息模塊化

背景

前段時間作了一些項目解耦重構和一些組件化的工做，推送是不少app種涉及到的應用場景，因此把推送模塊作了一些重構的工做，讓推送模塊可以獨立於業務適用於各類的業務場景。

本文的代碼連接：PTNotificationManager

分析

推送消息模塊和其餘模塊從技術角度來看是屬於同一級別的模塊，推送消息模塊爲了可以和其餘業務組件之間既有通訊又能解耦，這複合設計中的控制反轉原則，依賴的雙方依賴於對方的抽象而不依賴於具體的實現，觀察者模式就是一種典型的控制反轉場景，觀察者模式很適合推送模塊的獨立和解耦。

實現

觀察者模式簡析

觀察者模式類圖

這是一個簡單的觀察者的類圖結構

• 抽象接口 Subject 有一個註冊觀察者的方法
• 抽象接口 Observer 有一個獲取 Subject 數據更新的方法
• Subject 和 Observer 具體的子類重寫對應的方法，處理數據
• 有新的消息，ConcreateSubject 會把消息發送給已註冊的ConcreateObserver， ConcreateObserver 負責接收消息進行處理

代碼實現

抽象接口

OC接口是使用 protocol 實現的，定義觀察者（Observer）和被觀察主題（Subject）以下：

@protocol PTNotificationObservable;

@protocol PTNotificationObserver <NSObject>

- (void)update:(id<PTNotificationObservable>)sender data:(id)data;

@end


@protocol PTNotificationObservable <NSObject>

- (void)addObserver:(id<PTNotificationObserver>)observer;

@end
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具體實現

推送模塊管理類對應的是被觀察主題（Subject），定義了以下接口：

• APP啓動，初始化推送配置
• 處理註冊Token
• 處理接收消息
• 添加觀察者

頭文件以下：

#import <Foundation/Foundation.h>
#import "PTNotificationProtocllDefine.h"

#undef AS_SINGLETON
#define AS_SINGLETON \
+ (instancetype)sharedInstance;

#undef DEF_SINGLETON
#define DEF_SINGLETON \
+ (instancetype)sharedInstance{ \
static dispatch_once_t once; \
static id __singleton__; \
dispatch_once( &once, ^{ __singleton__ = [[self alloc] init]; } ); \
return __singleton__; \
} \


@interface PTNotificationManager : NSObject <PTNotificationObservable>

AS_SINGLETON

// 處理APP啓動，配置推送
- (void)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions;
// 處理註冊Token
- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken;
// 處理接收消息
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo;

// 添加觀察者
- (void)addObserver:(id<PTNotificationObserver>)observer;

- (void)testSendNotification;

@end
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集成的是第三方的友盟消息推送，全部裏面包含了友盟一些API的使用。
實現文件：

#import "PTNotificationManager.h"
#import "UMessage.h"
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 100000
#import <UserNotifications/UserNotifications.h>
#endif

#define UMengAppKey @"xxxxx"

@interface PTNotificationManager ()<UNUserNotificationCenterDelegate>
@property (nonatomic, strong) NSPointerArray* observers;
@end

@implementation PTNotificationManager

DEF_SINGLETON

- (void)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    //設置 AppKey 及 LaunchOptions
    [UMessage startWithAppkey:UMengAppKey launchOptions:launchOptions];
    //註冊通知
    [UMessage registerForRemoteNotifications];
    
    //iOS10必須加下面這段代碼。
    if ([[[UIDevice currentDevice] systemVersion]intValue] >= 10) {
        UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
        center.delegate=self;
        UNAuthorizationOptions types10=UNAuthorizationOptionBadge|UNAuthorizationOptionAlert|UNAuthorizationOptionSound;
        [center requestAuthorizationWithOptions:types10 completionHandler:^(BOOL granted, NSError * _Nullable error) {
            if (granted) {
                //點擊容許
            } else {
                //點擊不容許
            }
        }];
    }
    
    //若是你指望使用交互式(只有iOS 8.0及以上有)的通知，請參考下面註釋部分的初始化代碼
    if (([[[UIDevice currentDevice] systemVersion]intValue]>=8)&&([[[UIDevice currentDevice] systemVersion]intValue]<10)) {

// UIMutableUserNotificationAction *action1 = [[UIMutableUserNotificationAction alloc] init];
// action1.identifier = @"action1_identifier";
// action1.title=@"打開應用";
// action1.activationMode = UIUserNotificationActivationModeForeground;當點擊的時候啓動程序
//
// UIMutableUserNotificationAction *action2 = [[UIMutableUserNotificationAction alloc] init]; 第二按鈕
// action2.identifier = @"action2_identifier";
// action2.title=@"忽略";
// action2.activationMode = UIUserNotificationActivationModeBackground;當點擊的時候不啓動程序，在後臺處理
// action2.authenticationRequired = YES;須要解鎖才能處理，若是action.activationMode = UIUserNotificationActivationModeForeground;則這個屬性被忽略；
// action2.destructive = YES;
// UIMutableUserNotificationCategory *actionCategory1 = [[UIMutableUserNotificationCategory alloc] init];
// actionCategory1.identifier = @"category1";這組動做的惟一標示
// [actionCategory1 setActions:@[action1,action2] forContext:(UIUserNotificationActionContextDefault)];
// NSSet *categories = [NSSet setWithObjects:actionCategory1, nil];
// [UMessage registerForRemoteNotifications:categories];
    }
    //若是要在iOS10顯示交互式的通知，必須注意實現如下代碼
    if ([[[UIDevice currentDevice] systemVersion]intValue]>=10) {

// UNNotificationAction *action1_ios10 = [UNNotificationAction actionWithIdentifier:@"action1_ios10_identifier" title:@"打開應用" options:UNNotificationActionOptionForeground];
// UNNotificationAction *action2_ios10 = [UNNotificationAction actionWithIdentifier:@"action2_ios10_identifier" title:@"忽略" options:UNNotificationActionOptionForeground];
        //UNNotificationCategoryOptionNone
        //UNNotificationCategoryOptionCustomDismissAction 清除通知被觸發會走通知的代理方法
        //UNNotificationCategoryOptionAllowInCarPlay 適用於行車模式
// UNNotificationCategory *category1_ios10 = [UNNotificationCategory categoryWithIdentifier:@"category101" actions:@[action1_ios10,action2_ios10] intentIdentifiers:@[] options:UNNotificationCategoryOptionCustomDismissAction];
// NSSet *categories_ios10 = [NSSet setWithObjects:category1_ios10, nil];
// UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
// [center setNotificationCategories:categories_ios10];

    }
    
    //若是對角標，文字和聲音的取捨，請用下面的方法
    //UIRemoteNotificationType types7 = UIRemoteNotificationTypeBadge|UIRemoteNotificationTypeAlert|UIRemoteNotificationTypeSound;
    //UIUserNotificationType types8 = UIUserNotificationTypeAlert|UIUserNotificationTypeSound|UIUserNotificationTypeBadge;
    //[UMessage registerForRemoteNotifications:categories withTypesForIos7:types7 withTypesForIos8:types8];

    //for log
    [UMessage setLogEnabled:YES];
    
    // 應用從通知啓動
    NSDictionary* userInfo = [launchOptions objectForKey:UIApplicationLaunchOptionsRemoteNotificationKey];
    if (userInfo) {
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [self handleNotificationUserInfo:userInfo];
        });
    }
}

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
    //1.2.7版本開始不須要用戶再手動註冊devicetoken，SDK會自動註冊
    // [UMessage registerDeviceToken:deviceToken];
    
    NSString* tokenString = [self stringDevicetoken:deviceToken];
    NSLog(@"==tokenString = %@", tokenString);
    printf([[NSString stringWithFormat:@"\n\ntokenString = %@\n\n", tokenString] UTF8String]);
}

/** - (void)application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error { //若是註冊不成功，打印錯誤信息，能夠在網上找到對應的解決方案 //1.2.7版本開始自動捕獲這個方法，log以application:didFailToRegisterForRemoteNotificationsWithError開頭 } */

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo {
    [[NSNotificationCenter defaultCenter] postNotificationName:@"userInfoNotification" object:self userInfo:@{@"userinfo":[NSString stringWithFormat:@"%@",userInfo]}];
    //關閉友盟自帶的彈出框
    [UMessage setAutoAlert:NO];
    [UMessage didReceiveRemoteNotification:userInfo];
    if (application.applicationState != UIApplicationStateActive) {
        [self handleNotificationUserInfo:userInfo];
    }
}

// 添加觀察者
- (void)addObserver:(id<PTNotificationObserver>)observer {
    [self.observers addPointer:(__bridge void * _Nullable)(observer)];
}

- (void)testSendNotification {
    [self handleNotificationUserInfo:@{@"kkk": @"kkk"}];
}

- (void)handleNotificationUserInfo:(NSDictionary *)userInfo {
    for (id<PTNotificationObserver> observer in self.observers.allObjects) {
        [observer update:self data:userInfo];
    }
}

#pragma mark - ......::::::: UNUserNotificationCenterDelegate :::::::......

//iOS10新增：處理前臺收到通知的代理方法
-(void)userNotificationCenter:(UNUserNotificationCenter *)center willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions))completionHandler {
    NSDictionary * userInfo = notification.request.content.userInfo;
    if([notification.request.trigger isKindOfClass:[UNPushNotificationTrigger class]]) {
        //應用處於前臺時的遠程推送接受
        //必須加這句代碼
        [UMessage setAutoAlert:NO];
        [UMessage didReceiveRemoteNotification:userInfo];
    }else{
        //應用處於前臺時的本地推送接受
    }
}

//iOS10新增：處理後臺點擊通知的代理方法
- (void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(nonnull void (^)(void))completionHandler {
    NSDictionary * userInfo = response.notification.request.content.userInfo;
    if([response.notification.request.trigger isKindOfClass:[UNPushNotificationTrigger class]]) {
        //應用處於後臺時的遠程推送接受
        //必須加這句代碼
        [UMessage didReceiveRemoteNotification:userInfo];
        [self handleNotificationUserInfo:userInfo];
    }else{
        //應用處於後臺時的本地推送接受
    }
}


#pragma mark - ......::::::: Helper :::::::......

-(NSString *)stringDevicetoken:(NSData *)deviceToken {
    NSString *token = [deviceToken description];
    NSString *pushToken = [[[token stringByReplacingOccurrencesOfString:@"<"withString:@""] stringByReplacingOccurrencesOfString:@">"withString:@""] stringByReplacingOccurrencesOfString:@" " withString:@""];
    return pushToken;
}


#pragma mark - ......::::::: Lazy Load :::::::......

- (NSPointerArray *)observers {
    if (nil == _observers) {
        _observers = [NSPointerArray weakObjectsPointerArray];
    }
    return _observers;
}

@end
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使用方法：

• ViewController 實現了 PTNotificationObserver Protocol 做爲觀察者
• 重寫 - (void)update:(id<PTNotificationObservable>)sender data:(id)data 方法打印接收到的消息
• 在 - (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event 模擬讓消息模塊發送消息

@interface PTViewController () <PTNotificationObserver>

@end

@implementation PTViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    [[PTNotificationManager sharedInstance] addObserver:self];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


// 接收到消息
- (void)update:(id<PTNotificationObservable>)sender data:(id)data {
    NSLog(@"%@", data);
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [[PTNotificationManager sharedInstance] testSendNotification];
}
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使用cocopods集成

使用 pod lib create 命令建立私有庫

➜  DevPods pod lib create PTNotificationManager
Cloning `https://github.com/CocoaPods/pod-template.git` into `PTNotificationManager`.
Configuring PTNotificationManager template.

------------------------------

To get you started we need to ask a few questions, this should only take a minute.

If this is your first time we recommend running through with the guide: 
 - http://guides.cocoapods.org/making/using-pod-lib-create.html
 ( hold cmd and double click links to open in a browser. )


What language do you want to use?? [ Swift / ObjC ]
 > Objc

Would you like to include a demo application with your library? [ Yes / No ]
 > 
yes
Which testing frameworks will you use? [ Specta / Kiwi / None ]
 > None

Would you like to do view based testing? [ Yes / No ]
 > No

What is your class prefix?
 > PT

Running pod install on your new library.

Analyzing dependencies
Fetching podspec for `PTNotificationManager` from `../`
Downloading dependencies
Installing PTNotificationManager (0.1.0)
Generating Pods project
Integrating client project

[!] Please close any current Xcode sessions and use `PTNotificationManager.xcworkspace` for this project from now on.
Sending stats
Pod installation complete! There is 1 dependency from the Podfile and 1 total pod installed.

[!] Automatically assigning platform ios with version 9.3 on target PTNotificationManager_Example because no platform was specified. Please specify a platform for this target in your Podfile. See `https://guides.cocoapods.org/syntax/podfile.html#platform`.

 Ace! you're ready to go! We will start you off by opening your project in Xcode open 'PTNotificationManager/Example/PTNotificationManager.xcworkspace' To learn more about the template see `https://github.com/CocoaPods/pod-template.git`. To learn more about creating a new pod, see `http://guides.cocoapods.org/making/making-a-cocoapod`. ➜ DevPods 複製代碼

修改 PTNotificationManager.podspec 文件以下

Pod::Spec.new do |s|
  s.name             = 'PTNotificationManager'
  s.version          = '0.1.0'
  s.summary          = 'A short description of PTNotificationManager.'
  s.description      = <<-DESC Oh PTNotificationManager DESC

  s.homepage         = 'https://github.com/flypigrmvb/PTNotificationManager'
  s.license          = { :type => 'MIT', :file => 'LICENSE' }
  s.author           = { 'flypigrmvb' => '862709539@qq.com' }
  s.source           = { :git => 'https://github.com/flypigrmvb/PTNotificationManager.git', :tag => s.version.to_s }

  s.ios.deployment_target = '8.0'

  s.source_files = 'PTNotificationManager/Classes/**/*'

  # s.public_header_files = 'Pod/Classes/**/*.h'

    # 添加依賴的系統靜態庫
    s.libraries = 'xml2', 'z', 'c++', 'stdc++.6', 'sqlite3'
    # 添加系統的farme依賴庫
    s.frameworks = 'UIKit', 'MapKit'
    # 添加其餘Pod依賴庫
    s.dependency 'UMessage'
end
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Example項目的 Podfile 添加以下內容

platform :ios, '8.0'

inhibit_all_warnings!

target 'PTNotificationManager_Example' do
  pod 'PTNotificationManager', :path => '../'
  pod 'UMessage', :podspec => 'https://raw.githubusercontent.com/kkme/UMessage/master/UMessage.podspec'

end
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以上步驟Example項目就能夠跑起來了，完成了簡單的推送消息模塊的組件化和解耦，方便在不一樣的業主場景中使用。