飛線圖
簡介
QTEventBus 事件總線集中管理事件流,跟ReactiveCocoa函數(shù)響應(yīng)式編程框架類似(Functional reactive programming毫蚓，簡稱FRP）能很好的,省略膠水代碼.
Event(事件)
支持事件類型有NSString NSObject Notificaton QTJsonEvent QTAppEvent(應(yīng)用生命周期事件) 等同于RAC里的signal
Subscribe(訂閱)
訂閱先于事件發(fā)布
dispatch(發(fā)布)
事件源出發(fā)布需要傳遞的事件
使用前先訂閱事件
// QTSub(self, DemoEvent) 是個(gè)宏
[QTSub(self, DemoEvent) next:^(DemoEvent *event) {
NSLog(@"%ld",event.count);
}];
宏展開后
// self 事件訂閱者 _className_ 泛型指定了 next 回調(diào)參數(shù)類型 subscribeSharedBus 是通過NSObject擴(kuò)展里實(shí)現(xiàn)
#define QTSub(_object_,_className_) ((QTEventSubscriberMaker<_className_ *> *)[_object_ subscribeSharedBus:[_className_ class]])
subscribeSharedBus 在NSObject分類里實(shí)現(xiàn)
// 此處是對(duì) QTEventSubscriberMaker 做事件存儲(chǔ)以及封裝釋放的處理
- (QTEventSubscriberMaker *)subscribeSharedBus:(Class)eventClass{
return [QTEventBus shared].on(eventClass).freeWith(self);
}
// on是 QTEventSubscriberMaker對(duì)象的block屬性 用來
- (QTEventSubscriberMaker<id> *(^)(Class eventClass))on{
return ^QTEventSubscriberMaker *(Class eventClass){
return [[QTEventSubscriberMaker alloc] initWithEventBus:self
eventClass:eventClass];
};
}
// QTEventSubscriberMaker 對(duì)象
@interface QTEventSubscriberMaker()
- (instancetype)initWithEventBus:(QTEventBus *)eventBus
eventClass:(Class)eventClass;
@property (strong, nonatomic) Class eventClass; // 事件類型
@property (strong, nonatomic) NSObject * lifeTimeTracker; // QTEventSubscriberMaker釋放的時(shí)候用
@property (strong, nonatomic) dispatch_queue_t queue;// 事件響應(yīng)的隊(duì)列
@property (strong, nonatomic) NSMutableArray * eventSubTypes; // 存儲(chǔ)二級(jí)事件
@property (strong, nonatomic) QTEventBus * eventBus; // 事件處理對(duì)象
@property (copy, nonatomic) void(^hander)(__kindof NSObject *);// 訂閱者需要處理的任務(wù)
@end
// next:^(DemoEvent *event) { 將創(chuàng)建監(jiān)聽者 并保存至QTEventBusCollection中(內(nèi)部實(shí)現(xiàn)是雙向鏈表)
[QTSub(self, DemoEvent) next:^(DemoEvent *event) {
NSLog(@"%ld",event.count);
}];
- (id<QTEventToken>)next:(QTEventNextBlock)hander{
return self.next(hander);
}
- (id<QTEventToken>(^)(void(^)(id event)))next{
return ^id<QTEventToken>(void(^hander)(__kindof NSObject * event)){
self.hander = hander;
return [self.eventBus _createNewSubscriber:self];
};
}
- (id<QTEventToken>)_createNewSubscriber:(QTEventSubscriberMaker *)maker{
if (!maker.hander) {
return nil;
}
if (maker.eventSubTypes.count == 0) {//一級(jí)事件
_QTEventToken * token = [self _addSubscriberWithMaker:maker eventType:nil];
return token;
}
NSMutableArray * tokens = [[NSMutableArray alloc] init];
for (NSString * eventType in maker.eventSubTypes) {
_QTEventToken * token = [self _addSubscriberWithMaker:maker eventType:eventType];
[tokens addObject:token];
}
_QTComposeToken * token = [[_QTComposeToken alloc] initWithTokens:tokens];
return token;
}
- (_QTEventToken *)_addSubscriberWithMaker:(QTEventSubscriberMaker *)maker eventType:(NSString *)eventType{
__weak typeof(self) weakSelf = self;
NSString * eventKey = __generateUnqiueKey(maker.eventClass, eventType);
NSString * groupId = [self.prefix stringByAppendingString:eventKey];
NSString * uniqueId = [groupId stringByAppendingString:@([NSDate date].timeIntervalSince1970).stringValue];
_QTEventToken * token = [[_QTEventToken alloc] initWithKey:uniqueId];
BOOL isCFNotifiction = (maker.eventClass == [NSNotification class]);
if (eventType && isCFNotifiction) {
[self _addNotificationObserverIfNeeded:eventType];
}
// 銷毀時(shí)的回調(diào)
token.onDispose = ^(NSString *uniqueId) {
__strong typeof(self) strongSelf = weakSelf;
if (!strongSelf) {
return;
}
BOOL empty = [strongSelf.collection removeUniqueId:uniqueId ofKey:groupId];
if (empty && isCFNotifiction) {
[strongSelf _removeNotificationObserver:eventType];
}
};
使用runtime 關(guān)聯(lián)QTDisposeBag 管理監(jiān)聽對(duì)象 觸發(fā)時(shí)機(jī)在監(jiān)聽者如VC dealloc后會(huì)釋放關(guān)聯(lián)對(duì)象
//創(chuàng)建監(jiān)聽者
_QTEventSubscriber * subscriber = [[_QTEventSubscriber alloc] init];
subscriber.queue = maker.queue;
subscriber.handler = maker.hander;
subscriber.uniqueId = uniqueId;
if (maker.lifeTimeTracker) {
// 銷毀
[maker.lifeTimeTracker.eb_disposeBag addToken:token];
}
[self.collection addObject:subscriber forKey:groupId];
return token;
}
以上是訂閱事件做的工作.接下來看事件發(fā)布的處理
- (IBAction)dispatchEvent:(id)sender {
static long _count = 1;
DemoEvent * event = [[DemoEvent alloc] init];
event.count = _count;
_count ++;
[[QTEventBus shared] dispatch:event];
}
- (void)dispatch:(id<QTEvent>)event{
if (!event) {
return;
}
NSString * eventSubType = [event respondsToSelector:@selector(eventSubType)] ? [event eventSubType] : nil;
if (eventSubType) {
//二級(jí)事件
NSString * key = __generateUnqiueKey(event.class, eventSubType);
[self _publishKey:key event:event];
}
//一級(jí)事件
NSString * key = __generateUnqiueKey(event.class, nil);
[self _publishKey:key event:event];
}
根據(jù) key 到collection 取出訂閱者 并執(zhí)行handle任務(wù)
- (void)_publishKey:(NSString *)eventKey event:(NSObject *)event{
NSString * groupId = [self.prefix stringByAppendingString:eventKey];
NSArray * subscribers = [self.collection objectsForKey:groupId];
if (!subscribers || subscribers.count == 0) {
return;
}
for (_QTEventSubscriber * subscriber in subscribers) {
if (subscriber.queue) { //異步分發(fā)
dispatch_async(subscriber.queue, ^{
if (subscriber.handler) {
subscriber.handler(event);
}
});
}else{ //同步分發(fā)
if (subscriber.handler) {
subscriber.handler(event);
}
}
}
}
到此結(jié)束
總結(jié)
1, 訂閱者存儲(chǔ)使用字典加鏈表的方式
2,DSL鏈?zhǔn)骄幊?br>
3,泛型的應(yīng)用
4,釋放池的關(guān)聯(lián)
https://github.com/LeoMobileDeveloper/QTEventBus
