ReactiveCocoa簡介及作用

1.ReactiveCocoa簡介

ReactiveCocoa（簡稱為RAC）,是由Github開源的一個應(yīng)用于iOS和OS開發(fā)的新框架,Cocoa是蘋果整套框架的簡稱，因此很多蘋果框架喜歡以Cocoa結(jié)尾。

2.ReactiveCocoa作用

在我們iOS開發(fā)過程中，當(dāng)某些事件響應(yīng)的時候，需要處理某些業(yè)務(wù)邏輯,這些事件都用不同的方式來處理。

比如按鈕的點擊使用action，ScrollView滾動使用delegate，屬性值改變使用KVO等系統(tǒng)提供的方式。

其實這些事件，都可以通過RAC處理

ReactiveCocoa為事件提供了很多處理方法，而且利用RAC處理事件很方便，可以把要處理的事情，和監(jiān)聽的事情的代碼放在一起，這樣非常方便我們管理，就不需要跳到對應(yīng)的方法里。非常符合我們開發(fā)中高聚合，低耦合的思想

在RAC中最核心的類RACSiganl

````objc//RACSignal信號使用步驟：1：創(chuàng)建信號? 2:訂閱信號? 3: 發(fā)送信號//1：創(chuàng)建信號RACSignal *signal = [RACSignal createSignal:^RACDisposable *(id subscriber) {//didSubscribe調(diào)用:只有被訂閱了，才調(diào)用//didSubscribe作用:發(fā)送數(shù)據(jù)//3:發(fā)送信號[subscriber sendNext:@1];returnnil;? ? }];//2:訂閱信號[signal subscribeNext:^(idx) {//nextBlock調(diào)用：只有發(fā)送數(shù)據(jù)了才會調(diào)用//nextBlock作用：接受數(shù)據(jù)，展示UINSLog(@"%@",x);? ? }];

RACDisposable: 用于取消訂閱或者清理資源，當(dāng)信號發(fā)送完成或者發(fā)送錯誤的時候，就會自動觸發(fā)它。

--不想監(jiān)聽某個信號時，可以通過它主動取消訂閱信號。

-(void)racWithSignalDisposable{//1:創(chuàng)建信號RACSignal *signal = [RACSignal createSignal:^RACDisposable *(id subscriber) {? ? ? ? _subscriber = subscriber;//3發(fā)送信號[subscriber sendNext:@1];return[RACDisposable disposableWithBlock:^{NSLog(@"取消訂閱");? ? ? ? }];? ? }];//2:訂閱信號RACDisposable *disposable = [signal subscribeNext:^(idx) {NSLog(@"%@",x);? ? }];//主要訂閱者在就不會取消訂閱者[disposable dispose];}

RACSubject:RACSubject:信號提供者，自己可以充當(dāng)信號，又能發(fā)送信號。

使用場景:通常用來代替代理，有了它，就不必要定義代理了。

-(RACSubject *)subject{if(_subject ==nil) {? ? ? ? _subject = [RACSubject subject];? ? }return_subject;}-(IBAction)clickBtn:(UIButton*)btn{? ? [self.subjectsendNext:@1];}-(void)racWithDelegate{//訂閱[_redView.subjectsubscribeNext:^(idx) {NSLog(@"控制器做了一件事情%@",x);? ? }];}

RACTuple: 元組類,類似NSArray,用來包裝值.

-(void)racWtihTuple{//rac集合RACTuple *tuple = [RACTuple tupleWithObjectsFromArray:@[@"123",@"234",@1]];//取出rac集合中的第0個元素NSString*str =? tuple[0];NSLog(@"%@",str);}

RACSequence:RAC中的集合類，用于代替NSArray,NSDictionary,可以使用它來快速遍歷數(shù)組和字典。

-(void)racWithAarray{//rac遍歷數(shù)組//創(chuàng)建一個數(shù)組NSArray*arry = @[@"123",@"321",@"111"];//把數(shù)組轉(zhuǎn)變?yōu)橐粋€集合RACSequence *sequence = arry.rac_sequence;//把集合轉(zhuǎn)換為一個信號RACSignal *singnal = sequence.signal;//使用信號訂閱信息[singnal subscribeNext:^(idx) {NSLog(@"%@",x);? ? }];? ? [arry.rac_sequence.signalsubscribeNext:^(idx) {NSLog(@"%@",x);? ? }];}

實例：

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent*)event{self.person.userName= [NSStringstringWithFormat:@"zhangsan---%u",arc4random_uniform(100)];}//rac實現(xiàn)kvo-(void)racWithKvo{? ? [RACObserve(self.person, userName) subscribeNext:^(idx) {self.nameLabel.text= x;? ? }];}? [_accountTextFiled.rac_textSignalsubscribeNext:^(idx) {self.nameLabel.text= x;? ? }];

多個輸入文件作為信號源

多用于登陸等業(yè)務(wù)需求

p.p1 {margin:0.0px0.0px0.0px0.0px; font:11.0px'PingFang SC'; color:#4cbf57}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #ffffff}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #ffffff; min-height: 13.0px}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #93c86a}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #4cbf57}span.s1 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #c2349b}span.s4 {font-variant-ligatures: no-common-ligatures; color: #ffffff}span.s5 {font-variant-ligatures: no-common-ligatures; color: #00afca}span.s6 {font-variant-ligatures: no-common-ligatures; color: #8b84cf}span.s7 {font: 11.0px 'PingFang SC'; font-variant-ligatures: no-common-ligatures}span.s8 {font-variant-ligatures: no-common-ligatures; color: #93c86a}span.s9 {font-variant-ligatures: no-common-ligatures; color: #e44448}//多個文本框輸入信號組合使用-(void)racTextFiledsDemo{? ? RACSignal *nameSignal = [self.nameTextFiled rac_textSignal];? ? RACSignal *pwdSignal = [self.pwdTextFiled rac_textSignal];? ? NSArray *signals = @[nameSignal,pwdSignal];//訂閱信號[[RACSignal combineLatest:signals]subscribeNext:^(RACTuple *x) {? ? ? ? NSString *name = x.first;? ? ? ? NSString *pawd = x.second;? ? ? ? NSLog(@"%@%@",x,name);if(name.length>0&& pawd.length>0) {self.photoImageView.image = [UIImage imageNamed:@"Demo"];? ? ? ? }elseif(name.length >0|| pawd.length >0){self.photoImageView.image = [UIImage imageNamed:@"Demo1"];? ? ? ? }? ? }];}

rac_signalForSelector的使用，代替代理（不需要傳值的情況下）

p.p1{margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#4cbf57}p.p2 {margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#93c86a}p.p3 {margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#ffffff;min-height:13.0px}p.p4 {margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#ffffff}span.s1 {font-variant-ligatures: no-common-ligatures;color:#ffffff}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font:11.0px'PingFang SC';font-variant-ligatures:no-common-ligatures}span.s4 {font-variant-ligatures: no-common-ligatures;color:#c2349b}span.s5 {font-variant-ligatures: no-common-ligatures;color:#00afca}span.s6 {font-variant-ligatures: no-common-ligatures;color:#e44448}span.s7 {font-variant-ligatures: no-common-ligatures;color:#93c86a}? //rac_signalForSelector:監(jiān)聽某對象有沒有調(diào)用某方法? ? [[self.readView rac_signalForSelector:@selector(clickBtn:)] subscribeNext:^(id x) {NSLog(@"clickBtn");? ? }];[[self rac_signalForSelector:@selector(didReceiveMemoryWarning)]subscribeNext:^(id x) {NSLog(@"clickBtn");? ? }];

p.p1{margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#ffffff}p.p2 {margin:0.0px0.0px0.0px0.0px;font:11.0pxMenlo;color:#ffffff;min-height:13.0px}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures;color:#c2349b}@weakify(self)? ? [RACObserve(self.person, name) subscribeNext:^(id x) {? ? ? ? @strongify(self)

全部代碼

p.p1{margin:0.0px0.0px0.0px0.0px; font:11.0px Menlo; color:#ffffff}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #ffffff; min-height: 13.0px}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #e44448}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #4cbf57}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #93c86a}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'PingFang SC'; color: #4cbf57}p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #00afca}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #c2349b}span.s3 {font-variant-ligatures: no-common-ligatures; color: #ffffff}span.s4 {font-variant-ligatures: no-common-ligatures; color: #00afca}span.s5 {font: 11.0px 'PingFang SC'; font-variant-ligatures: no-common-ligatures}span.s6 {font-variant-ligatures: no-common-ligatures; color: #e44448}span.s7 {font-variant-ligatures: no-common-ligatures; color: #93c86a}span.s8 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s9 {font-variant-ligatures: no-common-ligatures; color: #8b84cf}span.s10 {font: 11.0px 'PingFang SC'; font-variant-ligatures: no-common-ligatures; color: #e44448}span.s11 {font-variant-ligatures: no-common-ligatures; color: #d28f5a}span.s12 {font-variant-ligatures: no-common-ligatures; color: #4cbf57}span.s13 {font: 11.0px 'PingFang SC'; font-variant-ligatures: no-common-ligatures; color: #4cbf57}}-(void)dealloc{NSLog(@"viewController dealloc");}//rac代替代理-(void)racWithDelegate{//? ? 1:rac的subject? 2:rac的select//rac_signalForSelector:監(jiān)聽某對象有沒有調(diào)用某方法[[self.readViewrac_signalForSelector:@selector(clickBtn:)] subscribeNext:^(idx) {NSLog(@"clickBtn");? ? }];? ? [[selfrac_signalForSelector:@selector(didReceiveMemoryWarning)] subscribeNext:^(idx) {NSLog(@"clickBtn");? ? }];}//多個文本框輸入信號組合使用-(void)racTextFiledsDemo{? ? RACSignal *nameSignal = [self.nameTextFiledrac_textSignal];? ? RACSignal *pwdSignal = [self.pwdTextFiledrac_textSignal];NSArray*signals = @[nameSignal,pwdSignal];//訂閱信號[[RACSignal combineLatest:signals]subscribeNext:^(RACTuple *x) {NSString*name = x.first;NSString*pawd = x.second;NSLog(@"%@%@",x,name);if(name.length>0&& pawd.length>0) {self.photoImageView.image= [UIImageimageNamed:@"Demo"];? ? ? ? }elseif(name.length>0|| pawd.length>0){self.photoImageView.image= [UIImageimageNamed:@"Demo1"];? ? ? ? }? ? }];}//rac及時刷新UI-(void)racWithUI{? ? [_nameTextFiled.rac_textSignalsubscribeNext:^(idx) {self.nameLabel.text= x;? ? }];}//rRAC中的集合類,用于代替NSArray,NSDictionary,可以使用它來快速遍歷數(shù)組和字典。-(void)racWithSeq{NSArray*array = @[@"7",@"3",@"4",@"5"];//? ? //把數(shù)組轉(zhuǎn)為一個集合//? ? RACSequence *sequence = array.rac_sequence;////? ? //把集合轉(zhuǎn)為一個信號//? ? RACSignal *signal = sequence.signal;////? ? //使用訂閱者訂閱信號//? ? [signal subscribeNext:^(id x) {////? ? ? ? NSLog(@"%@",x);//? ? }];[array.rac_sequence.signalsubscribeNext:^(idx) {NSLog(@"%@",x);? ? }];}-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent*)event{self.person.name= [NSStringstringWithFormat:@"liuYAHUA－－－%u",arc4random_uniform(100)];}//rac中的kvo-(void)racWithKvo{? ? @weakify(self)//觀察person的name屬性[RACObserve(self.person, name) subscribeNext:^(idx) {? ? ? ? @strongify(self)self.nameLabel.text= x;? ? }];}//rac中訂閱者的取消-(void)racWithSignalDisposable{//rac中最核心的就是信號? 1:創(chuàng)建信號? 2:訂閱信號? 3:發(fā)送信號//1:創(chuàng)建信號RACSignal *signal = [RACSignal createSignal:^RACDisposable *(id subscriber) {//didSubscribe調(diào)用：只有被訂閱了，才會調(diào)用//didSubscribe作用：發(fā)送數(shù)據(jù)_subscriber = subscriber;//3:發(fā)送信號[subscriber sendNext:@"劉亞華"];return[RACDisposable disposableWithBlock:^{NSLog(@"劉亞華被取消了");? ? ? ? }];? ? }];//2:訂閱信號RACDisposable *disposable =? [signal subscribeNext:^(idx) {//nextBlock調(diào)用：只有發(fā)送了數(shù)據(jù)才會調(diào)用//nextBlock作用：接受數(shù)據(jù)，展示UINSLog(@"%@",x);? ? }];//取消[disposable dispose];}-(void)racWithSignal{//rac中最核心的就是信號? 1:創(chuàng)建信號? 2:訂閱信號? 3:發(fā)送信號//1:創(chuàng)建信號RACSignal *signal = [RACSignal createSignal:^RACDisposable *(id subscriber) {//didSubscribe調(diào)用：只有被訂閱了，才會調(diào)用//didSubscribe作用：發(fā)送數(shù)據(jù)//3:發(fā)送信號[subscriber sendNext:@"劉亞華"];returnnil;? ? }];//2:訂閱信號[signal subscribeNext:^(idx) {//nextBlock調(diào)用：只有發(fā)送了數(shù)據(jù)才會調(diào)用//nextBlock作用：接受數(shù)據(jù)，展示UINSLog(@"%@",x);? ? }];}

＃鏈?zhǔn)骄幊?/p>

p.p1 {margin:0.0px0.0px0.0px0.0px; font:11.0px Menlo; color:#ffffff}p.p2 {margin:0.0px0.0px0.0px0.0px; font:11.0px Menlo; color: #ffffff; min-height:13.0px}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #c2349b}span.s3 {font-variant-ligatures: no-common-ligatures; color: #00afca}span.s4 {font-variant-ligatures: no-common-ligatures; color: #e44448}span.s5 {font-variant-ligatures: no-common-ligatures; color: #93c86a}-(void)run{? ? NSLog(@"run");}-(void)play{? ? NSLog(@"play");}-(Person *(^)(CGFloat))run1{return^(CGFloat DIS){? ? ? ? NSLog(@"run1%f",DIS);returnself;? ? };}-(Person *(^)(NSString *))play1{return^(NSString *qiu){? ? ? ? NSLog(@"play1%@",qiu);returnself;? ? };}

文／海綿寶寶不要哭（簡書作者）

原文鏈接：http://www.lxweimin.com/p/1d4248724ad2

著作權(quán)歸作者所有，轉(zhuǎn)載請聯(lián)系作者獲得授權(quán)，并標(biāo)注“簡書作者”。

最后編輯于 ：
?著作權(quán)歸作者所有,轉(zhuǎn)載或內(nèi)容合作請聯(lián)系作者
平臺聲明：文章內(nèi)容（如有圖片或視頻亦包括在內(nèi)）由作者上傳并發(fā)布，文章內(nèi)容僅代表作者本人觀點，簡書系信息發(fā)布平臺，僅提供信息存儲服務(wù)。

推薦閱讀更多精彩內(nèi)容