RAC集合類:

1. RACTuple:元組,類似NSArray,用來包裝值
2. RACSequence:RAC中集合,用于替代NSArray,NSDictionary可以使用它快速遍歷.

    NSArray *arr = @[@"12",@"2121",@1];
    NSDictionary *dic = @{@"name":@"zhangsan",@"age":@"15",@"height":@"165"};
    
    RACTuple *tuple = [RACTuple tupleWithObjectsFromArray:arr];
    NSLog(@"%@",tuple[0]);
    
    //將集合轉(zhuǎn)化為RACSequence集合
    RACSequence *sequence = arr.rac_sequence;
    RACSignal *singal = sequence.signal;
    [singal subscribeNext:^(id x) {
        NSLog(@"%@",x);
    }];
    //數(shù)組遍歷.
    [arr.rac_sequence.signal subscribeNext:^(id x) {
        NSLog(@"常用寫法%@",x);
    }];
    //字典遍歷RACTuple元組包裝相應(yīng)key:value
    [dic.rac_sequence.signal subscribeNext:^(id x) {
        NSLog(@"%@",x);
    }];

RAC開發(fā)中常見用法:

• 1. 代替代理
• 2. kvo
• 3. 通知
• 4. 監(jiān)聽事件
• 5. 文本框改變

代碼實現(xiàn)

//監(jiān)聽某個某個對象的方法是否調(diào)用:代理的rac另外一種實現(xiàn)
    [[self.reaVIew rac_signalForSelector:@selector(didClickAction:)] subscribeNext:^(id x) {
        NSLog(@"點擊按鈕,但無法傳值,x:%@",x);
        /*
         點擊按鈕,但無法傳值,x:<RACTuple: 0x60000039cea0> (
             "<UIButton: 0x7fc888c13890; frame = (97 63; 46 30); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x600000197e20>>"
         )
         */
    }];
    
    //替代kvo,需要手動導(dǎo)入另外的頭文件默認沒導(dǎo)入
    [self.reaVIew rac_observeKeyPath:@"frame" options:NSKeyValueObservingOptionNew observer:nil block:^(id value, NSDictionary *change, BOOL causedByDealloc, BOOL affectedOnlyLastComponent) {
        NSLog(@"frame屬性發(fā)生改變");
    }];
    [[self.view rac_valuesForKeyPath:@"frame" observer:nil]subscribeNext:^(id x) {
       NSLog(@"frame屬性發(fā)生改變%@",x);
    }];
    
    //監(jiān)聽事件
    UIButton *btn = [[UIButton alloc]init];
    [[btn rac_signalForControlEvents:UIControlEventTouchUpInside]subscribeNext:^(id x) {
        NSLog(@"按鈕點擊了");
    }];
    
    [[[NSNotificationCenter defaultCenter]rac_addObserverForName:UIKeyboardWillShowNotification object:nil]subscribeNext:^(id x) {
        NSLog(@"通知");
    }];
    
    //監(jiān)聽文本框
    UITextField *textField = [[UITextField alloc]init];
    [[textField rac_textSignal]subscribeNext:^(id x) {
        NSLog(@"文本框改變");
    }];