RACSignal,RACSubject,RACReplaySubject
- RACSignal
// **1. Create Signal**
RACSignal *signal = [RACSignal createSignal:^RACDisposable * _Nullable(id<RACSubscriber> _Nonnull subscriber) {
// The block, which is called whenever the signal is subscribed to; used primarily to send data
// **3. Send Data**
[subscriber sendNext:@"123456"];
// **3.1. Finished sending data**
[subscriber sendCompleted];
// Usually you can use return nil here; instead
return [RACDisposable disposableWithBlock:^{
// The block is called whenever the signal unsubscribes; used primarily to empty resources
// **4.1. Empty Resources**
NSLog(@"Signal resource emptied!");
}];
}];
// **2. Subscription Signal**
RACDisposable *disposable = [signal subscribeNext:^(id _Nullable x) {
NSLog(@"%@", x);
}];
// **4. Call to empty resources**
[disposable dispose];
-
RACSubject
// **1. Create Signal**
RACSubject *subject = [RACSubject subject];
// **2. Subscription Signal**
[subject subscribeNext:^(id _Nullable x) {
NSLog(@"%@", x);
}];
// **3. Send Data**
[subject sendNext:@"data"]; -
RACReplaySubject
// **1. Create Signal**
RACReplaySubject *subject = [RACReplaySubject subject];
// **2. Subscription Signal**
[subject subscribeNext:^(id _Nullable x) {
NSLog(@"%@", x);
}];
// **3. Send Data**
// In RACReplaySubject, you can send data before subscribing to a signal;
// RACSubject does not
[subject sendNext:@"replay"];
Be careful:
1. RACSubscriber: Represents the subscriber used to signal. This is a protocol, not a class, that must be complied with and implemented to become a subscriber.create a signal with a subscriber to help it send data.
2. RACDisposable: Used to unsubscribe or clean up resources, which is triggered automatically when the signal is sent or when an error is sent.
: If you do not want to listen to a signal, you can actively unsubscribe from it.
3. RACSubject: A signal provider who can act as both a signal and send a signal.(can replace agent)
4. RACReplaySubjet: Repeat the signal class (RACSubject subclass).
: The difference between RACReplaySubject and RACSubject is that RACReplaySubject can send a signal before subscribing to it; RACSubject cannot.
: If a signal is subscribed to once, it is necessary to repeat the previous value and use the repeat to provide the signal class.
: You can set the number of capacities to limit the number of values cached, that is, only the latest values are cached.
Replace proxy implementation with RACSubject
- WDYRedView.h
@interface WDYRedView : UIView
@property (nonatomic, strong) RACSubject *signalSubject;
@end- WDYRedView.m
@implementation WDYRedView
(RACSubject *)signalSubject {
if (_signalSubject == nil) { _signalSubject = [RACSubject subject];}
return _signalSubject;
}
(void)clickView:(UITapGestureRecognizer *)gesture {
[self.signalSubject sendNext:@"Clicked View View"];
}
(void)layoutSubviews {
[super layoutSubviews];
[self setBackgroundColor:[UIColor redColor]];
[self setUserInteractionEnabled:YES];
[self addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(clickView:)]];
}
@end- Called in Controller (click to post value)
// RACSubject instead of proxy implementation - > can pass value
WDYRedView *redView = [[WDYRedView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
[self.view addSubview:redView];
[redView.signalSubject subscribeNext:^(id _Nullable x) {
NSLog(@"%@", x);
}];