詳解如何使用ReactiveObjC

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概述

RAC架構框架圖

信號流程

基本使用

1、基本控件

UITextField

//監聽文本輸入
 [[_textField rac_textSignal] subscribeNext:^(NSString * _Nullable x) {
        NSLog(@"%@",x);
 }];
  
 
//可根據自己想要監聽的事件選擇
 [[_textField rac_signalForControlEvents:UIControlEventEditingChanged] subscribeNext:^(__kindof UIControl * _Nullable x) {
     NSLog(@"%@",x);
 }];
//添加條件 -- 下面表示輸入文字長度 > 10 時才會調用subscribeNext
 [[_textField.rac_textSignal filter:^BOOL(NSString * _Nullable value) {
     return value.length > 10;
 }] subscribeNext:^(NSString * _Nullable x) {
     NSLog(@"輸入框內容：%@", x); }];

UIButton

//監聽按鈕點擊事件
[[_btn rac_signalForControlEvents:UIControlEventTouchUpInside] subscribeNext:^(__kindof UIControl * _Nullable x) {
        NSLog(@"-->%@",x);
}];

計時器（interval、delay）

//類似timer
@weakify(self)
self.disposable = [[RACSignal interval:2 onScheduler:[RACScheduler mainThreadScheduler]] subscribeNext:^(NSDate * _Nullable x) {
        @strongify(self)
        NSLog(@"時間：%@", x); // x 是當前的時間
        //關閉計時器
        [self.disposable dispose];
}];
//延時
[[[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {
        [subscriber sendNext:@"延時2秒"];
        return nil;<br>}] delay:2] subscribeNext:^(id x) {
         
        NSLog(@"-->%@",x);
}];

2、監聽屬性變化

//監聽self的name屬性
[RACObserve(self, name) subscribeNext:^(id  _Nullable x) {
        NSLog(@"屬性的改變-->%@",x);
}];
[[self rac_valuesForKeyPath:@"name" observer:self] subscribeNext:^(id  _Nullable x) {
        NSLog(@"屬性的改變-->%@", x);
}];
//此處RAC宏相當於讓_label訂閱瞭_textField的文本變化信號
//賦值給label的text屬性
RAC(_label, text) = _textField.rac_textSignal;

3、遍歷數組和字典

//遍歷數組
 NSArray *array = @[@"1", @"2", @"3", @"4", @"5"];
[array.rac_sequence.signal subscribeNext:^(id  _Nullable x) {
      NSLog(@"內容-->%@", x)<br>}];

4、監聽 Notification 通知事件

[[[NSNotificationCenter defaultCenter] rac_addObserverForName:@"notification" object:nil] subscribeNext:^(NSNotification * _Nullable x) {
        NSLog(@"-->%@", x);
}];

5、代替Delegate代理

//監聽按鈕點擊方法的信號
//當執行完btnClickAction後會執行此訂閱
[[self rac_signalForSelector:@selector(btnClickAction:)] subscribeNext:^(RACTuple * _Nullable x) {
        NSLog(@"-->%@", x);
}];
-(void) btnClickAction:(UIButton *)btn
{
    NSLog(@"按鈕點擊");
}

二、RAC常用類

RACSignal

RACSignal *signal = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
      [subscriber sendNext:@"🍺🍺🍺🍺🍺🍺🍺"];
      [subscriber sendCompleted];
      return [RACDisposable disposableWithBlock:^{
          NSLog(@"銷毀瞭🍺🍺🍺");
      }];
  }];
  [signal subscribeNext:^(id  _Nullable x) {
      NSLog(@"%@",x);
  }];

RACSubject(可發送信號也可以訂閱信號)

RACTuple（元組）– 其內部就是封裝瞭數組，用起來跟數組差不多

//通過定值創建RACTuple
RACTuple *tuple = [RACTuple tupleWithObjects:@"1", @"2", @"3", nil];
//利用 RAC 宏快速封裝
RACTuple *tuple2 = RACTuplePack(@"1", @"2", @"3");
//從別的數組中獲取內容
RACTuple *tuple3 = [RACTuple tupleWithObjectsFromArray:@[@"1", @"2", @"3"]];
 
NSLog(@"元組-->%@", tuple3[0]);
NSLog(@"第一個元素-->%@", [tuple3 first]);
NSLog(@"最後一個元素-->%@", [tuple3 last]);

RACMulticastConnection — 用於當一個信號，被多次訂閱時，為瞭保證創建信號時，避免多次調用創建信號中的block

RACSignal *signal1 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
       [subscriber sendNext:@"signal1-->🍺🍺🍺🍺🍺🍺🍺"];
       [subscriber sendCompleted];
       return [RACDisposable disposableWithBlock:^{
           NSLog(@"signal1銷毀瞭");
       }];
   }];
    
   RACMulticastConnection *connection = [signal1 publish];
    
   [connection.signal subscribeNext:^(id  _Nullable x) {
       NSLog(@"subscribeNext-->1");
   }];
   [connection.signal subscribeNext:^(id  _Nullable x) {
       NSLog(@"subscribeNext-->2");
   }];
   [connection.signal subscribeNext:^(id  _Nullable x) {
       NSLog(@"subscribeNext-->3");
   }];
   [connection connect];

RACCommand — 可以監聽信號的狀態等

NSString *input = @"執行";
RACCommand *command = [[RACCommand alloc] initWithSignalBlock:^RACSignal * _Nonnull(id  _Nullable input) {
    NSLog(@"input-->%@",input);
    return [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
        [subscriber sendNext:@"🍺🍺🍺🍺🍺🍺🍺"];
        [subscriber sendError:[NSError errorWithDomain:@"error" code:-1 userInfo:nil]];
//            [subscriber sendCompleted];
        return [RACDisposable disposableWithBlock:^{
            NSLog(@"signal銷毀瞭");
        }];
    }];
}];
[command.executionSignals subscribeNext:^(RACSignal   * _Nullable x) {
    NSLog(@"executionSignals-->%@",x);
    [x subscribeNext:^(id  _Nullable x) {
        NSLog(@"executionSignals-->subscribeNext-->%@",x);
    }];
}];
[[command.executionSignals switchToLatest] subscribeNext:^(id  _Nullable x) {
    NSLog(@"switchToLatest-->%@",x);
}];
[command.executing subscribeNext:^(id  _Nullable x) {
    NSLog(@"executing-->%@",x);
}];
[command.errors subscribeNext:^(id  _Nullable x) {
    NSLog(@"errors-->%@",x);
}];
//開始執行
[command execute:input];

三、高級函數使用

1、連接信號、合並信號等

首先創建兩個信號signal1和signal2來演示

RACSignal *signal1 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
     [subscriber sendNext:@"signal1-->🍺🍺🍺🍺🍺🍺🍺"];
     [subscriber sendCompleted];
     return [RACDisposable disposableWithBlock:^{
         NSLog(@"signal1銷毀瞭");
     }];
 }];
 RACSignal *signal2 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
     [subscriber sendNext:@"signal2-->🍺🍺🍺🍺🍺🍺🍺"];
     [subscriber sendCompleted];
     return [RACDisposable disposableWithBlock:^{
         NSLog(@"signal2銷毀瞭");
     }];
 }];

1.1、 concat — 當多個信號發出的時候，有順序的接收信號

一個信號signal3去監聽signal1和signal2，必須是接收signal1完後才會接收signal2

RACSignal *signal3 = [signal1 concat:signal2];
  [signal3 subscribeNext:^(id  _Nullable x) {
      NSLog(@"signal3-->%@",x);
  }];

1.2、 combineLatestWith — 將多個信號合並起來，並且拿到各個信號的最新的值,必須每個合並的signal至少都有過一次sendNext，才會觸發合並的信號(訂閱者每次接收的參數都是所有信號的最新值),不論觸發哪個信號都會觸發合並的信號

一個信號signal3去監聽signal1和signal2，每次回調兩個信號的最新值

RACSignal *signal3 = [signal1 combineLatestWith:signal2];
   [signal3 subscribeNext:^(id  _Nullable x) {
       NSLog(@"%@",x);
   }];

PS：註釋signal1的sendNext方法，直接銷毀瞭，所以每個singal必須有sendNext方法

1.3、 then — 用於連接兩個信號，等待第一個信號完成，才會連接then返回的信號

RACSignal *signal3 = [signal1 then:^RACSignal * _Nonnull{
    return signal2;
}];
[signal3 subscribeNext:^(id  _Nullable x) {
    NSLog(@"signal3-->%@",x);
}];

1.4、 merge — 把多個信號合並為一個信號來監聽，任何一個信號有新值的時候就會調用

一個信號signal3去監聽signal1和signal2，每次回調一個信號

RACSignal *signal3 = [signal1 merge:signal2];
[signal3 subscribeNext:^(id  _Nullable x) {
    NSLog(@"signal3-->%@",x);
}];

1.5、 zipWith — 把兩個信號壓縮成一個信號，隻有當兩個信號都發出信號內容時，才會觸發

一個信號signal3去監聽signal1和signal2，但必須兩個信號都有發出（不需要同時，例如signal1信號發出瞭，signal2信號等瞭10秒之後發出，那麼signal3的訂閱回調是等signal2信號發出的那一刻觸發）

RACSignal *signal3 = [signal1 zipWith:signal2];
[signal3 subscribeNext:^(id  _Nullable x) {
    NSLog(@"signal3-->%@",x);
}];

1.6、 reduce 聚合 — 把多個信號的值按照自定義的組合返回

RACSignal *signal3 = [RACSignal combineLatest:@[signal1,signal2] reduce:^id(NSString *s1 ,NSString *s2){
    return [NSString stringWithFormat:@"%@ %@",s1,s2];
}];
[signal3 subscribeNext:^(id x) {
    NSLog(@"%@",x);
}];

2、flattenMap & map 映射

flattenMap 的底層實現是通過bind實現的

map 的底層實現是通過 flattenMap 實現的

//map事例
[[_textField.rac_textSignal map:^id _Nullable(NSString * _Nullable value) {
        return [NSString stringWithFormat:@"%@🍺🍺🍺🍺🍺🍺🍺",value];
    }] subscribeNext:^(id  _Nullable x) {
        NSLog(@"-->%@",x);
    }] ;
//flattenMap事例
 [[_textField.rac_textSignal flattenMap:^__kindof RACSignal * _Nullable(NSString * _Nullable value) {
        return [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
            [subscriber sendNext:[NSString stringWithFormat:@"%@🍺🍺🍺🍺🍺🍺🍺",value]];
            [subscriber sendCompleted];
            return [RACDisposable disposableWithBlock:^(){}];
        }];
    }] subscribeNext:^(id  _Nullable x) {
        NSLog(@"-->%@",x);
    }] ;

3、filter — 過濾、ignore — 忽略、distinctUntilChanged — 忽略相同

filter、ignore

//map事例
[[_textField.rac_textSignal map:^id _Nullable(NSString * _Nullable value) {
        return [NSString stringWithFormat:@"%@🍺🍺🍺🍺🍺🍺🍺",value];
    }] subscribeNext:^(id  _Nullable x) {
        NSLog(@"-->%@",x);
    }] ;
//flattenMap事例
 [[_textField.rac_textSignal flattenMap:^__kindof RACSignal * _Nullable(NSString * _Nullable value) {
        return [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
            [subscriber sendNext:[NSString stringWithFormat:@"%@🍺🍺🍺🍺🍺🍺🍺",value]];
            [subscriber sendCompleted];
            return [RACDisposable disposableWithBlock:^(){}];
        }];
    }] subscribeNext:^(id  _Nullable x) {
        NSLog(@"-->%@",x);
    }] ;

distinctUntilChanged

RACSubject *subject = [RACSubject subject];
   [[subject distinctUntilChanged] subscribeNext:^(id  _Nullable x) {
       NSLog(@"-->%@",x);
   }];
   [subject sendNext:@"123"];
   [subject sendNext:@"123"];
   [subject sendNext:@"123"];
   [subject sendNext:@"🍺🍺🍺🍺🍺🍺"];
   [subject sendNext:@"🍺🍺🍺🍺🍺🍺"];
   [subject sendCompleted];

以上就是詳解如何使用ReactiveObjC的詳細內容，更多關於如何使用ReactiveObjC的資料請關註WalkonNet其它相關文章！

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