RACSignal的使用基础

获得信号的方式

单元信号

RACSignal *signal1 = [RACSignal return:@"Some Value"];
RACSignal *signal2 = [RACSignal error:errorObject];
RACSignal *signal3 = [RACSignal empty];
RACSignal *signal4 = [RACSignal never];

动态信号

    RACSignal *signal5 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
        [subscriber sendNext:@1];
        [subscriber sendNext:@2];
        [subscriber sendError:errorObject];
        [subscriber sendCompleted];
        return [RACDisposable disposableWithBlock:^{
            
        }];
    }];

Cocoa桥接

    RACSignal *signal6 = [view rac_signalForSelector:@selector(setFrame:)];
    RACSignal *signal7 = [view rac_signalForControlEvents:UIControlEventTouchUpInside];
    RACSignal *signal8 = [view rac_willDeallocSignal];
    RACSignal *signal9 = RACObserve(view, backgroundColor);

信号转换

    RACSignal *signal10 = [signal1 map:^id _Nullable(NSString *  _Nullable value) {
        return [value substringFromIndex:1];
    }];

序列转换

    RACSignal *signal11 = sequence.signal;

订阅一个信号的方式

订阅方法

  [signal11 subscribeNext:^(id  _Nullable x) {
        NSLog(@"next value is %@", x);
    } error:^(NSError * _Nullable error) {
        NSLog(@"ops! Get some error: %@", error);
    } completed:^{
        NSLog(@"finish success");
    }];

绑定

  RAC(view,backgroundColor) = signal10;

Cocoa桥接

     [view rac_liftSelector:@selector(convertPoint:toView:) withSignals:signal1,signal2, nil];
    [view rac_liftSelector:@selector(convertPoint:toView:) withSignalsFromArray:@[signal1,signal2]];
    [view rac_liftSelector:@selector(convertRect:toLayer:) withSignalOfArguments:signal5];

订阅过程

 RACSignal *signal = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber>  _Nonnull subscriber) {
        [subscriber sendNext:@1];
        [subscriber sendNext:@2];
        [subscriber sendCompleted];
        return [RACDisposable disposableWithBlock:^{
            NSLog(@"disposed");
        }];
    }];
    
    RACDisposable *disposable = [signal subscribeNext:^(id  _Nullable x) {
        NSLog(@"next value is %@", x);
    } error:^(NSError * _Nullable error) {
        NSLog(@"Ops! Get some error:%@", error);
    } completed:^{
        NSLog(@"It finished");
    }];
    
    [disposable dispose];

元祖-RACTuple

RAC定义的一种数据类型
NSArray的简化版
其他语言中的意义
使用

  RACTuple *tuple = RACTuplePack(@1, @"second");
    
    id first = tuple.first;
    id second = tuple.second;
    id last = tuple.last;
    
    id index2 = tuple[1];//second
    NSLog(@"%@", index2);
    
    RACTupleUnpack(NSNumber *num, NSString *str) = tuple;
    NSLog(@"num is %@", num); //num is 1
}