移动互联网一浪高过一浪专题打包archszlizhong

1、OverViewCocoa开发现状ReactiveCocoaMVVMDemo使用经验Cocoa开发现状需要考虑的情况是否已经登录是否已经赞过赞的过程中不能操作与服务端交互完成后改变赞的状态- (void)likeButtonTappedif (self.hasLoggedIn) else / popup a login view- (void)likeButtonTappedif (self.hasLoggedIn) if (!self.isLiking) else/ popup a login view- (void)likeButtonTappedif (self.hasLoggedIn)

2、 if (!self.isLiking) if (self.hasLiked) else else/ popup a login view-(void)likeButtonTappedif (self.hasLoggedIn) if (!self.isLiking) if (self.hasLiked)self.isLikingself.api=YES;plete:self.isLiking = NO; self.likeButton.highlighted = NO;plete: else self.isLiking = YES; self.apiself.isLiking = NO;sel

3、f.likeButton.highlighted = YES; else / popup a login viewStateThe Art of Unix Programming“编程的本质是控制复杂度”State能有效增加复杂度BOOL visible;2 statesBOOL enabled;4 statesBOOL highlighted;8 statesBOOL selected;16 statesState是一种缓存“There are only two hard things in Computer Science: cache invalidation and naming th

4、ings”Phil Karlton如何消灭/减少State?搞定产品经理只做简单的App改行换一种编程思路？ReactiveCocoa走出舒适区Shunryu Suzuki“In the beginners mind there are many possibilities, in the experts mind there are few.”Input - Process - OutputInput键盘输入点击手势操作网络请求磁盘DelegatetableView:didSelectRowAtIndexPathBlock Callbackplete:(NSArray*)-Actionlog

5、outButtonTapped:TimerstimerWithTimeInterval:selector:userInfo:repeats:KVOOutputUI的变化Model的变化网络请求CrashSignalviewWillAppearuserLoggedInfetchLatestData&CombineLatestRACSignalcombineLatest:viewWillAppearSignal, loggedInSignal subscribeNext:(id x) / fetch latestdata;networkErrorserverErrorpresentError|me

6、rgeRACSignalmerge:netErrorSignal, serverErrorSignal subscribeNext:(id x) / present Error;filtermapanyNumberSignal filter:BOOL(NSNumber *number) return number intValue % 2;&|&mand通常用来表示某个Action常常跟UIControl绑定使用有几个重要属性executingexecutionSignalserrorsMVVMMVVMDemoRACObserve(self, shouldPopLoginView) subsc

7、ribeNext:(id x) / pop up login view;RAC(self, likeButton.highlighted) = mand.executionSignalsswitchToLatestmap:id(id value) / handle result return YES; / or NO;self.mand = mand allocinitWithEnabled:mand.executing not signalBlock:RACSignal *(id input) if (!self.hasLoggedIn) self.shouldPopLoginView =

8、YES;mand execute:nil; else return nil;登录用户名登录登录用户名登录RAC(self.loginButton, enabled) = formValid;RACSignal *formValid = RACSignalcombineLatest: self.usernameField.rac_textSignal, self.passwordField.rac_textSignal,reduce:(NSString *name, NSString *password) return name.length & password.length;登录用户名登录R

9、ACSignal *textColor = executing map:(NSNumber *x) return x.boolValue ? gray : black;RAC(self.usernameField.textColor) = textColor; RAC(self.passwordField.textColor) = textColor;RACSignal *notProcessing = executing map:(NSNumber *x) return (!x.boolValue);RAC(self.usernameField.enabled) = notProcessin

10、g; RAC(self.password.enabled) = notProcessing;iPhotoiPhotoRACObserve(viewModel, indexPath) subscribeNext:(NSIndexPath *indexPath) self.collectionViewscrollToItemAtIndexPath:indexPath;CellViewModel *cvm = viewModel.cellViewModelsindexPath.row;cvm.active = YES; CellViewModel *lastActiveCVM =viewModel.

11、lastActiveCellViewModel;lastActiveCVM.active = NO;viewModel.lastActiveCellViewModel = cvm;iPhoto- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView/ 根据scrollView算出indexPath viewModel.indexPath = indexPath;- (void)collectionView:(UICollectionView *)collectionViewdidSelectItemAtIndexPath:(

12、NSIndexPath *)indexPath/ 处理viewModel.indexPath = indexPath;注意事项使用经验解题思路性能调试内存使用sendNextScheduler使用property还是signalProperty TableView的处理RAC在花瓣的使用场景解题思路百思不得解想到法，但好像不够RAC算了，时间有限，还是回到熟悉的编程模式吧性能subscribeNext很慢，比纯KVO慢了1个数量级接收到变化比较慢，比纯KVO慢了大约5倍调试signal subscribeNext:(id x);调试signal subscribeNext:(id x);sendNext由于ObjectiveC语言的限制，无法得知next的值到底是哪种类型，使用起来略有不便，需要看注释/代码，才能知道传的是什么值，然后手动转一下。SchedulerdeliverOn:subscribeOn:使用property还是signalProperty如无必要，使用正常的property即可，外部可以对它RACObserve或KVOTableView的处理把每个TableViewCell视为一个独立的View，也给它提供一个cellViewModel，而这个c