RAC簡(jiǎn)介
RAC就是一個(gè)第三方庫庙睡，他可以大大簡(jiǎn)化你的代碼過程阅嘶。
官方的說巷折，ReactiveCocoa（其簡(jiǎn)稱為RAC）是由GitHub開源的一個(gè)應(yīng)用于iOS和OS X開發(fā)的新框架媳禁。RAC具有函數(shù)式編程和響應(yīng)式編程的特性轨奄。
為什么我們要學(xué)習(xí)RAC赚哗？
為了提高我們的開發(fā)效率嗦锐。RAC在某些特定情況下開發(fā)時(shí)可以大大簡(jiǎn)化代碼顶猜，并且目前來看安全可靠晌姚。
RAC高級(jí)用法--組合《iOS RAC - 組合》
我們來配置RAC
pod 'ReactiveObjC', '~> 3.0.0' //建議純oc代碼使用ReactiveObjC
下面介紹RAC的一些簡(jiǎn)單用法
按鈕添加點(diǎn)擊事件
[[btn rac_signalForControlEvents:UIControlEventTouchUpInside]subscribeNext:^(__kindof UIControl * _Nullable x) {
}];
KVO使用
//方法一
[_redView rac_observeKeyPath:@"frame" options:NSKeyValueObservingOptionNew observer:nil block:^(id value, NSDictionary *change, BOOL causedByDealloc, BOOL affectedOnlyLastComponent) {
NSLog(@"方法一 %@",value);
}];
//方法二
[[_redView rac_valuesForKeyPath:@"frame" observer:nil] subscribeNext:^(id _Nullable x) {
NSLog(@"方法二 %@",x);
}];
//方法三 宏寫法
[RACObserve(_redView, frame) subscribeNext:^(id _Nullable x) {
NSLog(@"方法三%@",x);
}];
對(duì)textfield文字改變的監(jiān)聽
[[self.textFild rac_textSignal] subscribeNext:^(id x) {
NSLog(@"%@",x);
}];
對(duì)Label imageView添加點(diǎn)擊事件
UILabel *mylabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 100, 20)];
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] init];
[[tap rac_gestureSignal] subscribeNext:^(id x) {
NSLog(@"tap");
}];
[mylabel addGestureRecognizer:tap];
[self.view addSubview:mylabel];
通知
- (void)viewDidLoad {
[super viewDidLoad];
[[[NSNotificationCenter defaultCenter] rac_addObserverForName:@"postData" object:nil] subscribeNext:^(NSNotification * _Nullable x) {
NSLog(@"%@",x);
}];
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[[NSNotificationCenter defaultCenter] postNotificationName:@"postData" object:@{@"a":@"1223"}];
}
定時(shí)器使用
-(void)btnClick{
self.time = 10;
//這個(gè)就是RAC中的GCD
//每一秒執(zhí)行一次,這里要加上釋放信號(hào),否則控制器推出后依舊會(huì)執(zhí)行,看具體需求吧
@weakify(self)
//RACDisposable* disposable
self.disposable = [[RACSignal interval:1.0 onScheduler:[RACScheduler mainThreadScheduler]] subscribeNext:^(NSDate * _Nullable x) {
@strongify(self)
self.time --;
NSString *title =self.time>0?[NSString stringWithFormat:@"剩余%ld",self.time]:@"重新發(fā)送";
[self.btn setTitle:title forState:UIControlStateNormal];
if (self.time == 0) {
[self.disposable dispose];
}
}];
}
/*
創(chuàng)建一個(gè)RACDisposable粤剧，調(diào)用disposable方法等時(shí)候就會(huì)進(jìn)入創(chuàng)建對(duì)象的block，把定時(shí)器釋放掉
這兩個(gè)宏就是為了解決循環(huán)引用的挥唠，且必須配套使用抵恋。
@weakify(self)
@strongify(self)
相當(dāng)于下面：
__weak typeof(self) weakSelf = self;
__strong typeof(weakSelf) strongSelf = weakSelf;
*/
多個(gè)信號(hào)同時(shí)執(zhí)行 rac_liftSelector
- 主要應(yīng)用一個(gè)頁面有多個(gè)請(qǐng)求，然后又要等到數(shù)據(jù)全部請(qǐng)求到宝磨，在刷新UI的時(shí)候
-(void)demo{
RACSignal *signal1 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber> _Nonnull subscriber) {
[subscriber sendNext:@"111"];
return nil;
}];
RACSignal *signal2 = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber> _Nonnull subscriber) {
[subscriber sendNext:@"22222"];
return nil;
}];
[self rac_liftSelector:@selector(refeshUI::) withSignals:signal1,signal2, nil] ;
}
-(void)refeshUI:(id)one :(id)two{
NSLog(@"%@---%@",one,two);
}
多個(gè)訂閱 RACMulticastConnection
- RACMulticastConnection其實(shí)是一個(gè)連接類弧关，就是當(dāng)一個(gè)信號(hào)被多次訂閱盅安，他可以幫我們避免多次調(diào)用創(chuàng)建信號(hào)中的block
RACSignal *signal=[RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber> _Nonnull subscriber) {
[subscriber sendNext:@"123444"];
return nil;
}];
RACMulticastConnection *mut = [signal publish];
[mut.signal subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[mut.signal subscribeNext:^(id _Nullable x) {
NSLog(@"22%@",x);
}];
[mut connect];
綁定信號(hào) bind
RACSubject *signal = [RACSubject subject];
[[signal bind:^RACSignalBindBlock _Nonnull{
return ^RACSignal *(id value, BOOL* stop){
NSLog(@"%@",value);
NSString *v = [NSString stringWithFormat:@"處理過的數(shù)據(jù)%@",value];
return [RACReturnSignal return:v];//需要導(dǎo)入頭文件#import "RACReturnSignal.h"
};
}] subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[signal sendNext:@"1111"];
映射
- 我們?cè)谑褂胢ap完成上面的功能
RACSubject *subject = [RACSubject subject];
[[subject map:^id _Nullable(id _Nullable value) {
return [NSString stringWithFormat:@"處理過的數(shù)據(jù)%@",value];
}] subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
} ];
[subject sendNext:@"11"];
- 我們?cè)谑褂胒lattenMap完成上面的功能
RACSubject*signalA = [RACSubject subject];
[[signalA flattenMap:^__kindof RACSignal * _Nullable(id _Nullable value) {
NSString *v = [NSString stringWithFormat:@"處理數(shù)據(jù):%@",value];
//這里需要返回一個(gè)信號(hào)
return [RACReturnSignal return:v];
}]subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[signalA sendNext:@"123"];
- flattenMap的獨(dú)特用法處理信號(hào)中的信號(hào)
RACSubject *subjectofsignal = [RACSubject subject];
RACSubject *subject1 = [RACSubject subject];
[[subjectofsignal flattenMap:^__kindof RACSignal * _Nullable(id _Nullable value) {
return value;
}]subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[subjectofsignal sendNext:subject1];
[subject1 sendNext:@"111"];
- flattenMap也可以處理雙重訂閱
- switchToLatest同樣可以處理雙重訂閱
RACSubject *subjectofsignal = [RACSubject subject];
RACSubject *subject1 = [RACSubject subject];
[subjectofsignal.switchToLatest subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[subjectofsignal sendNext:subject1];
[subject1 sendNext:@"111"];
過濾 filter
[[self.username.rac_textSignal filter:^BOOL(NSString * _Nullable value) {
return value.length>5;
}] subscribeNext:^(NSString * _Nullable x) {
NSLog(@"%@",x);
}];
忽略 ignore
RACSubject * subject = [RACSubject subject];
[[subject ignore:@"a"] subscribeNext:^(id _Nullable x) {
NSLog(@"%@",x);
}];
[subject sendNext:@"a"];
[subject sendNext:@"b"];
[subject sendNext:@"c"];
忽略相鄰重復(fù)數(shù)據(jù) distinctUntilChanged
RACSubject *subject = [RACSubject subject];
//忽略相鄰重復(fù)數(shù)據(jù)
[[subject distinctUntilChanged]subscribeNext:^(id _Nullable x) {
}];
[subject sendNext:@"1"];
[subject sendNext:@"1"];
[subject sendNext:@"2"];
[subject sendNext:@"1"];
[subject sendNext:@"1"];
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