1. takeUntil
takeUntil:someSignal 的作用是当someSignal sendNext时,当前的signal就sendCompleted,someSignal就像一个拳击裁判,哨声响起就意味着比赛终止。
它的常用场景之一是处理cell的button的点击事件,比如点击Cell的详情按钮,需要push一个VC,就可以这样:
[[[cell.detailButton rac_signalForControlEvents:UIControlEventTouchUpInside] takeUntil:cell.rac_prepareForReuseSignal] subscribeNext:^(id x) { // generate and push ViewController }];
如果不加takeUntil:cell.rac_prepareForReuseSignal,那么每次Cell被重用时,该button都会被addTarget:selector。
2.swtichToLatest
switchToLatest: 的作用是自动切换signal of signals到最后一个,比如之前的command.executionSignals就可以使用switchToLatest:。
3.interval
4.delay
next和complete事件延迟一段时间发出,而error时间仍立即发出
5.take
6.throttle
一段时间内如果有多个Next,只取最新的Next,之前的抛弃掉
7.startWith
8.replay
9.subcribeOn
10.deliverOn
11.then
忽略上个信号的Next,等上个信号complete后,再产生新的信号
/////////////////////////RACSignal (Operations)///////////////////////////
@interface RACSignal (Operations) /// Do the given block on `next`. This should be used to inject side effects into /// the signal. - (RACSignal *)doNext:(void (^)(id x))block; /// Do the given block on `error`. This should be used to inject side effects /// into the signal. - (RACSignal *)doError:(void (^)(NSError *error))block; /// Do the given block on `completed`. This should be used to inject side effects /// into the signal. - (RACSignal *)doCompleted:(void (^)(void))block; /// Send `next`s only if we don‘t receive another `next` in `interval` seconds. /// /// If a `next` is received, and then another `next` is received before /// `interval` seconds have passed, the first value is discarded. /// /// After `interval` seconds have passed since the most recent `next` was sent, /// the most recent `next` is forwarded on the scheduler that the value was /// originally received on. If +[RACScheduler currentScheduler] was nil at the /// time, a private background scheduler is used. /// /// Returns a signal which sends throttled and delayed `next` events. Completion /// and errors are always forwarded immediately. - (RACSignal *)throttle:(NSTimeInterval)interval; /// Throttles `next`s for which `predicate` returns YES. /// /// When `predicate` returns YES for a `next`: /// /// 1. If another `next` is received before `interval` seconds have passed, the /// prior value is discarded. This happens regardless of whether the new /// value will be throttled. /// 2. After `interval` seconds have passed since the value was originally /// received, it will be forwarded on the scheduler that it was received /// upon. If +[RACScheduler currentScheduler] was nil at the time, a private /// background scheduler is used. /// /// When `predicate` returns NO for a `next`, it is forwarded immediately, /// without any throttling. /// /// interval - The number of seconds for which to buffer the latest value that /// passes `predicate`. /// predicate - Passed each `next` from the receiver, this block returns /// whether the given value should be throttled. This argument must /// not be nil. /// /// Returns a signal which sends `next` events, throttled when `predicate` /// returns YES. Completion and errors are always forwarded immediately. - (RACSignal *)throttle:(NSTimeInterval)interval valuesPassingTest:(BOOL (^)(id next))predicate; /// Forwards `next` and `completed` events after delaying for `interval` seconds /// on the current scheduler (on which the events were delivered). /// /// If +[RACScheduler currentScheduler] is nil when `next` or `completed` is /// received, a private background scheduler is used. /// /// Returns a signal which sends delayed `next` and `completed` events. Errors /// are always forwarded immediately. - (RACSignal *)delay:(NSTimeInterval)interval; /// Resubscribes when the signal completes. - (RACSignal *)repeat; /// Execute the given block each time a subscription is created. /// /// block - A block which defines the subscription side effects. Cannot be `nil`. /// /// Example: /// /// // Write new file, with backup. /// [[[[fileManager /// rac_createFileAtPath:path contents:data] /// initially:^{ /// // 2. Second, backup current file /// [fileManager moveItemAtPath:path toPath:backupPath error:nil]; /// }] /// initially:^{ /// // 1. First, acquire write lock. /// [writeLock lock]; /// }] /// finally:^{ /// [writeLock unlock]; /// }]; /// /// Returns a signal that passes through all events of the receiver, plus /// introduces side effects which occur prior to any subscription side effects /// of the receiver. - (RACSignal *)initially:(void (^)(void))block; /// Execute the given block when the signal completes or errors. - (RACSignal *)finally:(void (^)(void))block; /// Divides the receiver‘s `next`s into buffers which deliver every `interval` /// seconds. /// /// interval - The interval in which values are grouped into one buffer. /// scheduler - The scheduler upon which the returned signal will deliver its /// values. This must not be nil or +[RACScheduler /// immediateScheduler]. /// /// Returns a signal which sends RACTuples of the buffered values at each /// interval on `scheduler`. When the receiver completes, any currently-buffered /// values will be sent immediately. - (RACSignal *)bufferWithTime:(NSTimeInterval)interval onScheduler:(RACScheduler *)scheduler; /// Collect all receiver‘s `next`s into a NSArray. nil values will be converted /// to NSNull. /// /// This corresponds to the `ToArray` method in Rx. /// /// Returns a signal which sends a single NSArray when the receiver completes /// successfully. - (RACSignal *)collect; /// Takes the last `count` `next`s after the receiving signal completes. - (RACSignal *)takeLast:(NSUInteger)count; /// Combines the latest values from the receiver and the given signal into /// RACTuples, once both have sent at least one `next`. /// /// Any additional `next`s will result in a new RACTuple with the latest values /// from both signals. /// /// signal - The signal to combine with. This argument must not be nil. /// /// Returns a signal which sends RACTuples of the combined values, forwards any /// `error` events, and completes when both input signals complete. - (RACSignal *)combineLatestWith:(RACSignal *)signal; /// Combines the latest values from the given signals into RACTuples, once all /// the signals have sent at least one `next`. /// /// Any additional `next`s will result in a new RACTuple with the latest values /// from all signals. /// /// signals - The signals to combine. If this collection is empty, the returned /// signal will immediately complete upon subscription. /// /// Returns a signal which sends RACTuples of the combined values, forwards any /// `error` events, and completes when all input signals complete. + (RACSignal *)combineLatest:(id<NSFastEnumeration>)signals; /// Combines signals using +combineLatest:, then reduces the resulting tuples /// into a single value using -reduceEach:. /// /// signals - The signals to combine. If this collection is empty, the /// returned signal will immediately complete upon subscription. /// reduceBlock - The block which reduces the latest values from all the /// signals into one value. It must take as many arguments as the /// number of signals given. Each argument will be an object /// argument. The return value must be an object. This argument /// must not be nil. /// /// Example: /// /// [RACSignal combineLatest:@[ stringSignal, intSignal ] reduce:^(NSString *string, NSNumber *number) { /// return [NSString stringWithFormat:@"%@: %@", string, number]; /// }]; /// /// Returns a signal which sends the results from each invocation of /// `reduceBlock`. + (RACSignal *)combineLatest:(id<NSFastEnumeration>)signals reduce:(id (^)())reduceBlock; /// Sends the latest `next` from any of the signals. /// /// Returns a signal that passes through values from each of the given signals, /// and sends `completed` when all of them complete. If any signal sends an error, /// the returned signal sends `error` immediately. + (RACSignal *)merge:(id<NSFastEnumeration>)signals; /// Merges the signals sent by the receiver into a flattened signal, but only /// subscribes to `maxConcurrent` number of signals at a time. New signals are /// queued and subscribed to as other signals complete. /// /// If an error occurs on any of the signals, it is sent on the returned signal. /// It completes only after the receiver and all sent signals have completed. /// /// This corresponds to `Merge<TSource>(IObservable<IObservable<TSource>>, Int32)` /// in Rx. /// /// maxConcurrent - the maximum number of signals to subscribe to at a /// time. If 0, it subscribes to an unlimited number of /// signals. - (RACSignal *)flatten:(NSUInteger)maxConcurrent; /// Ignores all `next`s from the receiver, waits for the receiver to complete, /// then subscribes to a new signal. /// /// block - A block which will create or obtain a new signal to subscribe to, /// executed only after the receiver completes. This block must not be /// nil, and it must not return a nil signal. /// /// Returns a signal which will pass through the events of the signal created in /// `block`. If the receiver errors out, the returned signal will error as well. - (RACSignal *)then:(RACSignal * (^)(void))block; /// Concats the inner signals of a signal of signals. - (RACSignal *)concat; /// Aggregate `next`s with the given start and combination. - (RACSignal *)aggregateWithStart:(id)start reduce:(id (^)(id running, id next))reduceBlock; /// Aggregate `next`s with the given start and combination. The start factory /// block is called to get a new start object for each subscription. - (RACSignal *)aggregateWithStartFactory:(id (^)(void))startFactory reduce:(id (^)(id running, id next))reduceBlock; /// Invokes -setKeyPath:onObject:nilValue: with `nil` for the nil value. - (RACDisposable *)setKeyPath:(NSString *)keyPath onObject:(NSObject *)object; /// Binds the receiver to an object, automatically setting the given key path on /// every `next`. When the signal completes, the binding is automatically /// disposed of. /// /// Sending an error on the signal is considered undefined behavior, and will /// generate an assertion failure in Debug builds. /// /// A given key on an object should only have one active signal bound to it at any /// given time. Binding more than one signal to the same property is considered /// undefined behavior. /// /// keyPath - The key path to update with `next`s from the receiver. /// object - The object that `keyPath` is relative to. /// nilValue - The value to set at the key path whenever `nil` is sent by the /// receiver. This may be nil when binding to object properties, but /// an NSValue should be used for primitive properties, to avoid an /// exception if `nil` is sent (which might occur if an intermediate /// object is set to `nil`). /// /// Returns a disposable which can be used to terminate the binding. - (RACDisposable *)setKeyPath:(NSString *)keyPath onObject:(NSObject *)object nilValue:(id)nilValue; /// Sends NSDate.date every `interval` seconds. /// /// interval - The time interval in seconds at which the current time is sent. /// scheduler - The scheduler upon which the current NSDate should be sent. This /// must not be nil or +[RACScheduler immediateScheduler]. /// /// Returns a signal that sends the current date/time every `interval` on /// `scheduler`. + (RACSignal *)interval:(NSTimeInterval)interval onScheduler:(RACScheduler *)scheduler; /// Sends NSDate.date at intervals of at least `interval` seconds, up to /// approximately `interval` + `leeway` seconds. /// /// The created signal will defer sending each `next` for at least `interval` /// seconds, and for an additional amount of time up to `leeway` seconds in the /// interest of performance or power consumption. Note that some additional /// latency is to be expected, even when specifying a `leeway` of 0. /// /// interval - The base interval between `next`s. /// scheduler - The scheduler upon which the current NSDate should be sent. This /// must not be nil or +[RACScheduler immediateScheduler]. /// leeway - The maximum amount of additional time the `next` can be deferred. /// /// Returns a signal that sends the current date/time at intervals of at least /// `interval seconds` up to approximately `interval` + `leeway` seconds on /// `scheduler`. + (RACSignal *)interval:(NSTimeInterval)interval onScheduler:(RACScheduler *)scheduler withLeeway:(NSTimeInterval)leeway; /// Take `next`s until the `signalTrigger` sends `next` or `completed`. /// /// Returns a signal which passes through all events from the receiver until /// `signalTrigger` sends `next` or `completed`, at which point the returned signal /// will send `completed`. - (RACSignal *)takeUntil:(RACSignal *)signalTrigger; /// Take `next`s until the `replacement` sends an event. /// /// replacement - The signal which replaces the receiver as soon as it sends an /// event. /// /// Returns a signal which passes through `next`s and `error` from the receiver /// until `replacement` sends an event, at which point the returned signal will /// send that event and switch to passing through events from `replacement` /// instead, regardless of whether the receiver has sent events already. - (RACSignal *)takeUntilReplacement:(RACSignal *)replacement; /// Subscribe to the returned signal when an error occurs. - (RACSignal *)catch:(RACSignal * (^)(NSError *error))catchBlock; /// Subscribe to the given signal when an error occurs. - (RACSignal *)catchTo:(RACSignal *)signal; /// Runs `tryBlock` against each of the receiver‘s values, passing values /// until `tryBlock` returns NO, or the receiver completes. /// /// tryBlock - An action to run against each of the receiver‘s values. /// The block should return YES to indicate that the action was /// successful. This block must not be nil. /// /// Example: /// /// // The returned signal will send an error if data values cannot be /// // written to `someFileURL`. /// [signal try:^(NSData *data, NSError **errorPtr) { /// return [data writeToURL:someFileURL options:NSDataWritingAtomic error:errorPtr]; /// }]; /// /// Returns a signal which passes through all the values of the receiver. If /// `tryBlock` fails for any value, the returned signal will error using the /// `NSError` passed out from the block. - (RACSignal *)try:(BOOL (^)(id value, NSError **errorPtr))tryBlock; /// Runs `mapBlock` against each of the receiver‘s values, mapping values until /// `mapBlock` returns nil, or the receiver completes. /// /// mapBlock - An action to map each of the receiver‘s values. The block should /// return a non-nil value to indicate that the action was successful. /// This block must not be nil. /// /// Example: /// /// // The returned signal will send an error if data cannot be read from /// // `fileURL`. /// [signal tryMap:^(NSURL *fileURL, NSError **errorPtr) { /// return [NSData dataWithContentsOfURL:fileURL options:0 error:errorPtr]; /// }]; /// /// Returns a signal which transforms all the values of the receiver. If /// `mapBlock` returns nil for any value, the returned signal will error using /// the `NSError` passed out from the block. - (RACSignal *)tryMap:(id (^)(id value, NSError **errorPtr))mapBlock; /// Returns the first `next`. Note that this is a blocking call. - (id)first; /// Returns the first `next` or `defaultValue` if the signal completes or errors /// without sending a `next`. Note that this is a blocking call. - (id)firstOrDefault:(id)defaultValue; /// Returns the first `next` or `defaultValue` if the signal completes or errors /// without sending a `next`. If an error occurs success will be NO and error /// will be populated. Note that this is a blocking call. /// /// Both success and error may be NULL. - (id)firstOrDefault:(id)defaultValue success:(BOOL *)success error:(NSError **)error; /// Blocks the caller and waits for the signal to complete. /// /// error - If not NULL, set to any error that occurs. /// /// Returns whether the signal completed successfully. If NO, `error` will be set /// to the error that occurred. - (BOOL)waitUntilCompleted:(NSError **)error; /// Defer creation of a signal until the signal‘s actually subscribed to. /// /// This can be used to effectively turn a hot signal into a cold signal. + (RACSignal *)defer:(RACSignal * (^)(void))block; /// Every time the receiver sends a new RACSignal, subscribes and sends `next`s and /// `error`s only for that signal. /// /// The receiver must be a signal of signals. /// /// Returns a signal which passes through `next`s and `error`s from the latest /// signal sent by the receiver, and sends `completed` when both the receiver and /// the last sent signal complete. - (RACSignal *)switchToLatest; /// Switches between the signals in `cases` as well as `defaultSignal` based on /// the latest value sent by `signal`. /// /// signal - A signal of objects used as keys in the `cases` dictionary. /// This argument must not be nil. /// cases - A dictionary that has signals as values. This argument must /// not be nil. A RACTupleNil key in this dictionary will match /// nil `next` events that are received on `signal`. /// defaultSignal - The signal to pass through after `signal` sends a value for /// which `cases` does not contain a signal. If nil, any /// unmatched values will result in /// a RACSignalErrorNoMatchingCase error. /// /// Returns a signal which passes through `next`s and `error`s from one of the /// the signals in `cases` or `defaultSignal`, and sends `completed` when both /// `signal` and the last used signal complete. If no `defaultSignal` is given, /// an unmatched `next` will result in an error on the returned signal. + (RACSignal *)switch:(RACSignal *)signal cases:(NSDictionary *)cases default:(RACSignal *)defaultSignal; /// Switches between `trueSignal` and `falseSignal` based on the latest value /// sent by `boolSignal`. /// /// boolSignal - A signal of BOOLs determining whether `trueSignal` or /// `falseSignal` should be active. This argument must not be nil. /// trueSignal - The signal to pass through after `boolSignal` has sent YES. /// This argument must not be nil. /// falseSignal - The signal to pass through after `boolSignal` has sent NO. This /// argument must not be nil. /// /// Returns a signal which passes through `next`s and `error`s from `trueSignal` /// and/or `falseSignal`, and sends `completed` when both `boolSignal` and the /// last switched signal complete. + (RACSignal *)if:(RACSignal *)boolSignal then:(RACSignal *)trueSignal else:(RACSignal *)falseSignal; /// Add every `next` to an array. Nils are represented by NSNulls. Note that this /// is a blocking call. /// /// **This is not the same as the `ToArray` method in Rx.** See -collect for /// that behavior instead. /// /// Returns the array of `next` values, or nil if an error occurs. - (NSArray *)toArray; /// Add every `next` to a sequence. Nils are represented by NSNulls. /// /// This corresponds to the `ToEnumerable` method in Rx. /// /// Returns a sequence which provides values from the signal as they‘re sent. /// Trying to retrieve a value from the sequence which has not yet been sent will /// block. @property (nonatomic, strong, readonly) RACSequence *sequence; /// Creates and returns a multicast connection. This allows you to share a single /// subscription to the underlying signal. - (RACMulticastConnection *)publish; /// Creates and returns a multicast connection that pushes values into the given /// subject. This allows you to share a single subscription to the underlying /// signal. - (RACMulticastConnection *)multicast:(RACSubject *)subject; /// Multicasts the signal to a RACReplaySubject of unlimited capacity, and /// immediately connects to the resulting RACMulticastConnection. /// /// Returns the connected, multicasted signal. - (RACSignal *)replay; /// Multicasts the signal to a RACReplaySubject of capacity 1, and immediately /// connects to the resulting RACMulticastConnection. /// /// Returns the connected, multicasted signal. - (RACSignal *)replayLast; /// Multicasts the signal to a RACReplaySubject of unlimited capacity, and /// lazily connects to the resulting RACMulticastConnection. /// /// This means the returned signal will subscribe to the multicasted signal only /// when the former receives its first subscription. /// /// Returns the lazily connected, multicasted signal. - (RACSignal *)replayLazily; /// Sends an error after `interval` seconds if the source doesn‘t complete /// before then. /// /// The error will be in the RACSignalErrorDomain and have a code of /// RACSignalErrorTimedOut. /// /// interval - The number of seconds after which the signal should error out. /// scheduler - The scheduler upon which any timeout error should be sent. This /// must not be nil or +[RACScheduler immediateScheduler]. /// /// Returns a signal that passes through the receiver‘s events, until the stream /// finishes or times out, at which point an error will be sent on `scheduler`. - (RACSignal *)timeout:(NSTimeInterval)interval onScheduler:(RACScheduler *)scheduler; /// Creates and returns a signal that delivers its events on the given scheduler. /// Any side effects of the receiver will still be performed on the original /// thread. /// /// This is ideal when the signal already performs its work on the desired /// thread, but you want to handle its events elsewhere. /// /// This corresponds to the `ObserveOn` method in Rx. - (RACSignal *)deliverOn:(RACScheduler *)scheduler; /// Creates and returns a signal that executes its side effects and delivers its /// events on the given scheduler. /// /// Use of this operator should be avoided whenever possible, because the /// receiver‘s side effects may not be safe to run on another thread. If you just /// want to receive the signal‘s events on `scheduler`, use -deliverOn: instead. - (RACSignal *)subscribeOn:(RACScheduler *)scheduler; /// Groups each received object into a group, as determined by calling `keyBlock` /// with that object. The object sent is transformed by calling `transformBlock` /// with the object. If `transformBlock` is nil, it sends the original object. /// /// The returned signal is a signal of RACGroupedSignal. - (RACSignal *)groupBy:(id<NSCopying> (^)(id object))keyBlock transform:(id (^)(id object))transformBlock; /// Calls -[RACSignal groupBy:keyBlock transform:nil]. - (RACSignal *)groupBy:(id<NSCopying> (^)(id object))keyBlock; /// Sends an [NSNumber numberWithBool:YES] if the receiving signal sends any /// objects. - (RACSignal *)any; /// Sends an [NSNumber numberWithBool:YES] if the receiving signal sends any /// objects that pass `predicateBlock`. /// /// predicateBlock - cannot be nil. - (RACSignal *)any:(BOOL (^)(id object))predicateBlock; /// Sends an [NSNumber numberWithBool:YES] if all the objects the receiving /// signal sends pass `predicateBlock`. /// /// predicateBlock - cannot be nil. - (RACSignal *)all:(BOOL (^)(id object))predicateBlock; /// Resubscribes to the receiving signal if an error occurs, up until it has /// retried the given number of times. /// /// retryCount - if 0, it keeps retrying until it completes. - (RACSignal *)retry:(NSInteger)retryCount; /// Resubscribes to the receiving signal if an error occurs. - (RACSignal *)retry; /// Sends the latest value from the receiver only when `sampler` sends a value. /// The returned signal could repeat values if `sampler` fires more often than /// the receiver. Values from `sampler` are ignored before the receiver sends /// its first value. /// /// sampler - The signal that controls when the latest value from the receiver /// is sent. Cannot be nil. - (RACSignal *)sample:(RACSignal *)sampler; /// Ignores all `next`s from the receiver. /// /// Returns a signal which only passes through `error` or `completed` events from /// the receiver. - (RACSignal *)ignoreValues; /// Converts each of the receiver‘s events into a RACEvent object. /// /// Returns a signal which sends the receiver‘s events as RACEvents, and /// completes after the receiver sends `completed` or `error`. - (RACSignal *)materialize; /// Converts each RACEvent in the receiver back into "real" RACSignal events. /// /// Returns a signal which sends `next` for each value RACEvent, `error` for each /// error RACEvent, and `completed` for each completed RACEvent. - (RACSignal *)dematerialize; /// Inverts each NSNumber-wrapped BOOL sent by the receiver. It will assert if /// the receiver sends anything other than NSNumbers. /// /// Returns a signal of inverted NSNumber-wrapped BOOLs. - (RACSignal *)not; /// Performs a boolean AND on all of the RACTuple of NSNumbers in sent by the receiver. /// /// Asserts if the receiver sends anything other than a RACTuple of one or more NSNumbers. /// /// Returns a signal that applies AND to each NSNumber in the tuple. - (RACSignal *)and; /// Performs a boolean OR on all of the RACTuple of NSNumbers in sent by the receiver. /// /// Asserts if the receiver sends anything other than a RACTuple of one or more NSNumbers. /// /// Returns a signal that applies OR to each NSNumber in the tuple. - (RACSignal *)or; @end
时间: 2024-10-18 09:13:21