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[操作系统]ReactiveCocoa学习总结


最近一直断断续续学习关于ReactiveCocoa的知识内容,对于它的一些基础内容将通过本文进行一个总结,主要是一些入门知识

一:RACSignal一些运用

@interface RACSignalTestViewController ()@property(nonatomic,strong)RACSignal *mySignal,*secondSingl;@end

-(RACSignal *)mySignal{  if (!_mySignal) {    _mySignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {      [subscriber sendNext:@10];      [subscriber sendCompleted];      return nil;    }];  }    return _mySignal;}-(RACSignal *)secondSingl{  if (!_secondSingl) {    _secondSingl=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {      [subscriber sendNext:@20];      [subscriber sendCompleted];      return nil;    }];  }  return _secondSingl;}

先创建两个RACSignal的内容;将用于接下来的一些操作

  //map运用 返回的值作为next的参数  [[self.mySignal map:^id(NSNumber *value) {    return [value integerValue]>5?@"踏浪帅":@"有点小";  }] subscribeNext:^(NSString *str) {    NSLog(@"map处理完成的值为:%@",str);  }];    //filter:过滤信号,使用它可以获取满足条件的信号.  [[self.mySignal filter:^BOOL(NSNumber *item) {    return [item integerValue]>5;  }] subscribeNext:^(NSNumber *x) {    NSLog(@"filter当前的值%ld",[x integerValue]);  }];      //ignore:忽略完某些值的信号.当答合被ignore的值时就不会执行next  [[self.mySignal ignore:@10] subscribeNext:^(id x) {    NSLog(@"ignore当前的值:%@",x);  }];    //distinctUntilChanged:当上一次的值和当前的值有明显的变化就会发出信号,否则会被忽略掉。  [[self.mySignal distinctUntilChanged] subscribeNext:^(id x) {    NSLog(@"distinctUntilChanged当前的值:%@",x);  }];    //take:从开始一共取N次的信号  //takeLast:取最后N次的信号,前提条件,订阅者必须调用完成,因为只有完成,就知道总共有多少信号.  //takeUntil:(RACSignal *):获取信号直到某个信号执行完成  //skip:(NSUInteger):跳过几个信号,不接受。

运行结果:

MobileProject[885:18784] map处理完成的值为:踏浪帅2016-02-02 16:03:07.643 MobileProject[885:18784] filter当前的值102016-02-02 16:03:07.644 MobileProject[885:18784] distinctUntilChanged当前的值:10

1.2:一些组合的操作

  //concat:按一定顺序拼接信号,当多个信号发出的时候,有顺序的接收信号  RACSignal *concatSignal=[self.mySignal concat:self.secondSingl];  [concatSignal subscribeNext:^(id x) {    NSLog(@"concat拼接的值:%@",x);  }];    //then:用于连接两个信号,当第一个信号完成,才会连接then返回的信号  [[self.mySignal then:^RACSignal *{    @strongify(self);    return self.secondSingl;  }] subscribeNext:^(id x) {    //// 只能接收到第二个信号的值,也就是then返回信号的值    NSLog(@"then当前的值为:%@",x);  }];      //merge:把多个信号合并为一个信号,任何一个信号有新值的时候就会调用  RACSignal *mergeSignal=[self.mySignal merge:self.secondSingl];  [mergeSignal subscribeNext:^(id x) {    NSLog(@"merge当前的值为:%@",x);  }];      //combineLatest:将多个信号合并起来,并且拿到各个信号的最新的值,必须每个合并的signal至少都有过一次sendNext,两个信号的内容合并成一个元组RACTuple,才会触发合并的信号。  RACSignal *combineLatestSignal=[self.mySignal combineLatestWith:self.secondSingl];  [combineLatestSignal subscribeNext:^(id x) {    NSLog(@"combineLastest当前的值为:%@",x);  }];      //zipWith:把两个信号压缩成一个信号,只有当两个信号同时发出信号内容时,并且把两个信号的内容合并成一个元组RACTuple,才会触发压缩流的next事件。  RACSignal *zipWithSignal=[self.mySignal zipWith:self.secondSingl];  [zipWithSignal subscribeNext:^(RACTuple *tuple) {    NSLog(@"zipWith当前的值为:%@",tuple);        NSLog(@"zipWith中的RACTuple共有几个值:%ld",tuple.count);        NSLog(@"zipWith中的RACTuple第一个值为:%@",tuple.first);        NSLog(@"zipWith中的RACTuple最后一个值为:%@",tuple.last);  }];      //reduce聚合:用于信号发出的内容是元组,把信号发出元组的值聚合成一个值 特别是combineLatestWith,zipWith这种返回元组的RACTuple,reduceblcok中的参数,有多少信号组合,reduceblcok就有多少参数,每个参数就是之前信号发出的内容  RACSignal *reduceSignal=[RACSignal combineLatest:@[self.mySignal,self.secondSingl] reduce:^id(NSNumber *num1 ,NSNumber *num2){    NSLog(@"combineLastest结合reduct的第一个值为:%ld 第二个值为:%ld",[num1 integerValue],[num2 integerValue]);    return ([num1 integerValue]>10&&[num2 integerValue]>15)?@"两个都符合要求":@"都没有答合要求";  }];  [reduceSignal subscribeNext:^(id x) {    NSLog(@"reduce当前的值为:%@",x);  }];

运行结果:

MobileProject[885:18784] concat拼接的值:102016-02-02 16:03:07.645 MobileProject[885:18784] concat拼接的值:202016-02-02 16:03:07.646 MobileProject[885:18784] then当前的值为:202016-02-02 16:03:07.646 MobileProject[885:18784] merge当前的值为:102016-02-02 16:03:07.646 MobileProject[885:18784] merge当前的值为:202016-02-02 16:03:07.647 MobileProject[885:18784] combineLastest当前的值为:<RACTuple: 0x7ff5ca606860> (  10,  20)2016-02-02 16:03:07.648 MobileProject[885:18784] zipWith当前的值为:<RACTuple: 0x7ff5ca60ab80> (  10,  20)2016-02-02 16:03:07.648 MobileProject[885:18784] zipWith中的RACTuple共有几个值:22016-02-02 16:03:07.648 MobileProject[885:18784] zipWith中的RACTuple第一个值为:102016-02-02 16:03:07.648 MobileProject[885:18784] zipWith中的RACTuple最后一个值为:202016-02-02 16:03:07.649 MobileProject[885:18784] combineLastest结合reduct的第一个值为:10 第二个值为:202016-02-02 16:03:07.720 MobileProject[885:18784] reduce当前的值为:都没有答合要求

1.3:其它一些操作:

  //doNext: 执行Next之前,会先执行这个Block,可以做一些初使化的功能,doCompleted: 执行sendCompleted之前,会先执行这个Block  [[[self.mySignal doNext:^(id x) {    NSLog(@"doNext当前的值:%@",x);  }] doCompleted:^{    NSLog(@"doComplete 执行到了");  }] subscribeNext:^(id x) {    NSLog(@"测试doNext,doComplete的值:%@",x);  }];    //switchToLatest:用于signalOfSignals(信号的信号),有时候信号也会发出信号,会在signalOfSignals中,获取signalOfSignals发送的最新信号。  RACSubject *signalOfSignals = [RACSubject subject];  RACSubject *signal = [RACSubject subject];    // 获取信号中信号最近发出信号,订阅最近发出的信号。  // 注意switchToLatest:只能用于信号中的信号  [signalOfSignals.switchToLatest subscribeNext:^(id x) {        NSLog(@"switchToLatest%@",x);  }];  [signalOfSignals sendNext:signal];  [signal sendNext:@1];    //deliverOn: 内容传递切换到制定线程中,副作用在原来线程中,把在创建信号时block中的代码称之为副作用。  //subscribeOn: 内容传递和副作用都会切换到制定线程中。'      //timeout:超时,可以让一个信号在一定的时间后,自动报错。  [[self.mySignal timeout:1 onScheduler:[RACScheduler currentScheduler]]   subscribeNext:^(id x) {     NSLog(@"timeout当前的值:%@",x);   } error:^(NSError *error) {     NSLog(@"timeout 超时了");   }];      //delay 延迟发送next。  [[self.mySignal delay:2] subscribeNext:^(id x) {    NSLog(@"delay执行%@",x);  }];      //retry重试 :只要失败,就会重新执行创建信号中的block,直到成功.  __block int i = 0;  [[[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {        if (i == 10) {      [subscriber sendNext:@100];    }else{      NSLog(@"接收到错误");      [subscriber sendError:nil];    }    i++;        return nil;      }] retry] subscribeNext:^(id x) {        NSLog(@"retry当前的值:%@",x);      } error:^(NSError *error) {      }];      //普通执行多次订阅  RACSignal *oneSignal = [[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {    [subscriber sendNext:@1];    [subscriber sendNext:@2];    return nil;  }] replay];  [oneSignal subscribeNext:^(id x) {    NSLog(@"第一个没有replay执行的内容:%@",x);  }];  [oneSignal subscribeNext:^(id x) {    NSLog(@"第二个没有replay执行的内容:%@",x);  }];      //replay重放:当一个信号被多次订阅,反复播放内容  RACSignal *replaySignal = [[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {    [subscriber sendNext:@1];    [subscriber sendNext:@2];    return nil;  }] replay];    [replaySignal subscribeNext:^(id x) {    NSLog(@"replay第一个订阅者%@",x);  }];    [replaySignal subscribeNext:^(id x) {    NSLog(@"replay第二个订阅者%@",x);  }];      //interval 定时:每隔一段时间发出信号  [[RACSignal interval:1 onScheduler:[RACScheduler currentScheduler]] subscribeNext:^(id x) {    NSLog(@"interval一直在执行:%@",x);  }];    //throttle节流:当某个信号发送比较频繁时,可以使用节流,在某一段时间不发送信号内容,过了一段时间获取信号的最新内容发出。

运行结果:

2016-02-02 16:03:07.720 MobileProject[885:18784] doNext当前的值:102016-02-02 16:03:07.720 MobileProject[885:18784] 测试doNext,doComplete的值:102016-02-02 16:03:07.721 MobileProject[885:18784] doComplete 执行到了2016-02-02 16:03:07.721 MobileProject[885:18784] switchToLatest12016-02-02 16:03:07.722 MobileProject[885:18784] timeout当前的值:102016-02-02 16:03:07.722 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.723 MobileProject[885:18784] 第一个没有replay执行的内容:12016-02-02 16:03:07.723 MobileProject[885:18784] 第一个没有replay执行的内容:22016-02-02 16:03:07.723 MobileProject[885:18784] 第二个没有replay执行的内容:12016-02-02 16:03:07.723 MobileProject[885:18784] 第二个没有replay执行的内容:22016-02-02 16:03:07.724 MobileProject[885:18784] replay第一个订阅者12016-02-02 16:03:07.724 MobileProject[885:18784] replay第一个订阅者22016-02-02 16:03:07.724 MobileProject[885:18784] replay第二个订阅者12016-02-02 16:03:07.724 MobileProject[885:18784] replay第二个订阅者22016-02-02 16:03:07.838 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.838 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.838 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.838 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.839 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.865 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.865 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.865 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.866 MobileProject[885:18784] 接收到错误2016-02-02 16:03:07.866 MobileProject[885:18784] retry当前的值:1002016-02-02 16:03:08.726 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:08 +00002016-02-02 16:03:09.724 MobileProject[885:18784] delay执行102016-02-02 16:03:09.725 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:09 +00002016-02-02 16:03:10.726 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:10 +00002016-02-02 16:03:11.724 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:11 +00002016-02-02 16:03:12.727 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:12 +00002016-02-02 16:03:13.725 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:13 +00002016-02-02 16:03:14.730 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:14 +00002016-02-02 16:03:15.726 MobileProject[885:18784] interval一直在执行:2016-02-02 08:03:15 +0000

 

二:关于RACCommand的一些知识

@interface TestRacViewController ()@property(nonatomic,strong)UITextField *userNameText;@property(strong,nonatomic)NSString *username;@property(nonatomic,strong)UIButton *loginButton,*racCommendButton,*errCommendButton,*mainThreadButton,*netWorkButton,*testButton;@property(nonatomic,strong)RACCommand *otherMyRaccomand,*mainThreadCommend,*netWorkCommend,*testPropertyCommend;@end

 

//布局-(void)loadPage{  if (!self.userNameText) {    self.userNameText=[[UITextField alloc]init];    self.userNameText.backgroundColor=[UIColor whiteColor];    self.userNameText.placeholder=@"输入用户名";    [self.view addSubview:self.userNameText];    [self.userNameText mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.view.mas_top).with.offset(70);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.loginButton)  {    self.loginButton=[[UIButton alloc]init];    [self.loginButton setTitle:@"响应" forState:UIControlStateNormal];    self.loginButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.loginButton];    [self.loginButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.userNameText.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.racCommendButton)  {    self.racCommendButton=[[UIButton alloc]init];    [self.racCommendButton setTitle:@"RacCommend测试" forState:UIControlStateNormal];    self.racCommendButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.racCommendButton];    [self.racCommendButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.loginButton.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.errCommendButton)  {    self.errCommendButton=[[UIButton alloc]init];    [self.errCommendButton setTitle:@"ERROR测试" forState:UIControlStateNormal];    self.errCommendButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.errCommendButton];    [self.errCommendButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.racCommendButton.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.mainThreadButton)  {    self.mainThreadButton=[[UIButton alloc]init];    [self.mainThreadButton setTitle:@"主线程上运行" forState:UIControlStateNormal];    self.mainThreadButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.mainThreadButton];    [self.mainThreadButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.errCommendButton.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.netWorkButton)  {    self.netWorkButton=[[UIButton alloc]init];    [self.netWorkButton setTitle:@"属性测试" forState:UIControlStateNormal];    self.netWorkButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.netWorkButton];    [self.netWorkButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.mainThreadButton.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }    if(!self.testButton)  {    self.testButton=[[UIButton alloc]init];    [self.testButton setTitle:@"测试特性" forState:UIControlStateNormal];    self.testButton.backgroundColor=[UIColor blueColor];    [self.view addSubview:self.testButton];    [self.testButton mas_makeConstraints:^(MASConstraintMaker *make) {      make.left.mas_equalTo(self.view.mas_left).with.offset(15);      make.top.mas_equalTo(self.netWorkButton.mas_bottom).with.offset(20);      make.right.mas_equalTo(self.view.mas_right).with.offset(-15);      make.height.mas_equalTo(@40);    }];  }}

一些定义

//创建一个信号代码-(RACSignal *)testSignal{  RACSignal *signal = [RACSignal createSignal:^ RACDisposable * (id<RACSubscriber> subscriber) {    NSLog(@"创建信号");    [subscriber sendNext:@"Hi 我是一个信号"];    [subscriber sendCompleted];    return nil;  }];  return signal;}//创建一个命令响应-(RACCommand *)testCommend{  @weakify(self);  RACCommand *myCommend=[[RACCommand alloc] initWithSignalBlock:^RACSignal *(id input) {    RACSignal *authSignal=[RACSignal empty];    @strongify(self);           authSignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {           //可以根据要求加条件进行判断是否创建信号           if ([self.username isEqualToString:@"wjy"]) {           NSLog(@"符合要求");           [subscriber sendNext:@"我完成的命令响应"];           [subscriber sendCompleted];           }           else           {             //错误             [subscriber sendError:[NSError errorWithDomain:@"报错了" code:1 userInfo:nil]];           }         return nil;      }];    //materialize是为了处理拿不到error的问题    return [authSignal materialize];  }];    return myCommend;}//创建属性的RACCommand-(RACCommand *)otherMyRaccomand{  if (!_otherMyRaccomand) {    _otherMyRaccomand=[[RACCommand alloc] initWithSignalBlock:^RACSignal *(id input) {      NSLog(@"执行到新的RACCommand");      RACSignal *otherSignal=[RACSignal empty];      otherSignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {        if ([self.username isEqualToString:@"wjy"]) {          [subscriber sendNext:@"我肯定可以运行的"];          [subscriber sendCompleted];        }        else        {          [subscriber sendError:[NSError errorWithDomain:@"报错了" code:401 userInfo:nil]];        }        return nil;      }];      return otherSignal;    }];  }  return _otherMyRaccomand;}//创建主线程上运行-(RACCommand *)mainThreadCommend{  @weakify(self);  if (!_mainThreadCommend) {  _mainThreadCommend=[[RACCommand alloc] initWithSignalBlock:^RACSignal *(id input) {    RACSignal *authSignal=[RACSignal empty];    @strongify(self);        authSignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {      @strongify(self);      //可以根据要求加条件进行判断是否创建信号      if ([self.username isEqualToString:@"wjy"]) {        [subscriber sendNext:@(YES)];        [subscriber sendCompleted];      }      else      {        //错误        [subscriber sendError:[NSError errorWithDomain:@"报错了" code:1 userInfo:nil]];      }      return nil;    }];    return authSignal;  }];  }  return _mainThreadCommend;}//特性测试-(RACCommand *)testPropertyCommend{  if (!_testPropertyCommend) {      }    return _testPropertyCommend;}-(RACSignal *)nettestSignal{  RACSignal *authSignal=[RACSignal empty];    authSignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {    LogInApi *reg = [[LogInApi alloc] initWithUsername:self.username password:@"123456"];    [reg startWithCompletionBlockWithSuccess:^(YTKBaseRequest *request) {      LoginModel *model=[[LoginModel alloc]initWithString:request.responseString error:nil];      [subscriber sendNext:model];      [subscriber sendCompleted];    } failure:^(YTKBaseRequest *request) {      [subscriber sendError:[NSError errorWithDomain:@"报错了" code:1 userInfo:nil]];    }];    return nil;  }];  return authSignal;}-(RACSignal *)netSignal{  RACSignal *authSignal=[RACSignal empty];  authSignal=[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {    [subscriber sendNext:@"测试"];    [subscriber sendCompleted];    return nil;  }];  return authSignal;}//RACSubject的运用-(RACSubject *)testSubject{  RACSubject *sub=[RACSubject subject];  [sub sendNext:@"我是RACSubject"];  return sub;}

运用的内容:

  [self loadPage];  @weakify(self);    //把左边的属性跟右边信号signal的sendNext值绑定 distinctUntilChanged为了当值相同时不执行  RAC(self,username)=[self.userNameText.rac_textSignal distinctUntilChanged];    //监听username是否有变化,有变化就会执行subscribeNext 这个属性要支持KVO 可变数组就不可以  [RACObserve(self, username) subscribeNext:^(NSString *x) {    NSLog(@"你当前输入的值为:%@",x);  }];    //UIAlertView跟RAC结合  UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"" message:@"Alert" delegate:nil cancelButtonTitle:@"取消" otherButtonTitles:@"确定", nil];  [[alertView rac_buttonClickedSignal] subscribeNext:^(NSNumber *indexNumber) {    if ([indexNumber intValue] == 1) {      NSLog(@"你点了确定");    } else {      NSLog(@"你点了取消");    }  }];  [alertView show];    //Button响应事件  [[self.loginButton   rac_signalForControlEvents:UIControlEventTouchUpInside]    subscribeNext:^(UIButton *x) {     @strongify(self);     [[self testSignal] subscribeNext:^(id x) {       NSLog(@"当前执行值为:%@",x);     }];   }];        //Button用命令式运行 switchToLatest处理信号中传递的参数为信号  self.racCommendButton.rac_command=[self testCommend];    //这个绑定要放在executionSignals执行前面 否则只会有一个执行完成会响应  [self.racCommendButton.rac_command.executing subscribeNext:^(id x) {    if ([x boolValue]) {      NSLog(@"rac_command正在执行中");    }    else    {      NSLog(@"rac_command执行完成");    }  }];    //dematerialize处理可以响应处理跟完成的内容  [self.racCommendButton.rac_command.executionSignals subscribeNext:^(RACSignal *execution) {    [[[execution dematerialize] deliverOn:[RACScheduler mainThreadScheduler]] subscribeNext:^(id x) {      NSLog(@"提示内容:%@",x);    } error:^(NSError *error) {       NSLog(@"racCommend出错了");    }];  }];      //关于otherMyRaccomand的方式  self.errCommendButton.rac_command=self.otherMyRaccomand;    [self.otherMyRaccomand.executionSignals.switchToLatest subscribeNext:^(id x) {    NSLog(@"完成了 %@",x);  }];    //这边要注意是在errors 里面执行subscribeNext  不是执行subscribeError  [self.otherMyRaccomand.errors subscribeNext:^(NSError *error) {    NSLog(@"出错了 %@",error);  }];      //主线程上操作  self.mainThreadButton.rac_command=self.mainThreadCommend;  [[[self.mainThreadCommend.executionSignals.switchToLatest map:^id(id value) {    if ([value boolValue]) {      return @"跳浪帅";    }    else    {      return @"出太阳好么";    }  }] deliverOn:[RACScheduler mainThreadScheduler]] subscribeNext:^(NSString *str) {    UIAlertView *alert=[[UIAlertView alloc]initWithTitle:@"我是弹出窗" message:[NSString stringWithFormat:@"%@",str] delegate:nil cancelButtonTitle:@"取消" otherButtonTitles:@"确定", nil];    [alert show];  }];    //网络请求  //Button响应事件  [[self.netWorkButton   rac_signalForControlEvents:UIControlEventTouchUpInside]   subscribeNext:^(id x) {     [[[self netSignal] flattenMap:^RACStream *(id value) {       return [RACReturnSignal return:[NSString stringWithFormat:@"%@ 我已经被改变了成为另外一个信号",value]];     }]     subscribeNext:^(id x) {       NSLog(@"输出的内容:%@",x);     }];       }];  

因为代码中已经有相应的注解,所以文字说明就比较少,若有不明白可以留言;