在我的项目中,我试图通过MVVM工作,
所以在.h文件中的VM中
所以在.h文件中的VM中
@property (nonatomic,strong) NSArray *cities;
在.m文件中
- (NSArray *)cities {
return [[GPCity allObjects] valueForKey:@"name"];
}
GPCity是一个RLMObject子类
如何通过ReactiveCocoa绑定此(我的意思是看所有城市更新/添加/删除)？
就像是：
RAC(self,cities) = [[GPCity allObjects] map:(GPCity *)city {return city.name;}];
解决方法
您可以在RAC信号中包装Realm更改通知：
@interface RLMResults (RACSupport)
- (RACSignal *)gp_signal;
@end
@implementation RLMResults (RACSupport)
- (RACSignal *)gp_signal {
return [RACSignal createSignal:^(id<RACSubscriber> subscriber) {
id token = [self.realm addNotificationBlock:^(NSString *notification,RLMRealm *realm) {
if (notification == RLMRealmDidChangeNotification) {
[subscriber sendNext:self];
}
}];
return [RACDisposable disposableWithBlock:^{
[self.realm removeNotification:token];
}];
}];
}
@end
然后做：
RAC(self,cities) = [[[RLMObject allObjects] gp_signal]
map:^(RLMResults<GPCity *> *cities) { return [cities valueForKey:@"name"]; }];
不幸的是,这会在每次写入事务后更新信号,而不仅仅是修改城市的信号.一旦Realm 0.98与support for per-RLMResults notifications一起发布,您将能够执行以下操作,只有在更新GPCity对象时才会更新：
@interface RLMResults (RACSupport)
- (RACSignal *)gp_signal;
@end
@implementation RLMResults (RACSupport)
- (RACSignal *)gp_signal {
return [RACSignal createSignal:^(id<RACSubscriber> subscriber) {
id token = [self addNotificationBlock:^(RLMResults *results,NSError *error) {
if (error) {
[subscriber sendError:error];
}
else {
[subscriber sendNext:results];
}
}];
return [RACDisposable disposableWithBlock:^{
[token stop];
}];
}];
}
@end
