小编End*_*ama的帖子

目前有一种方法可以使用Facebook Pop框架进行自动布局,还是必须使用弹簧和支柱？我一直在阅读它是可能的,但我不知道语法是什么能够为视图的顶部约束设置动画.

所以我试图使用rest调用从数据库中获取一组Leaderboard对象.didLoadObjects返回0个对象,即使映射看起来是正确的:

 RKObjectManager *svc = [RKObjectManager sharedManager];
 NSString *resourcePath = leaderboardResourcePath;
 RKObjectMapping* mapping = [svc.mappingProvider objectMappingForClass:[Leaderboard class]];
 RKObjectLoader *loader = [[RKObjectManager sharedManager] loadObjectsAtResourcePath:resourcePath objectMapping:mapping delegate:self];

这是didLoadObjects方法

- (void)objectLoader:(RKObjectLoader*)objectLoader didLoadObjects:(NSArray*)objects { 
    if ([objectLoader.resourcePath isEqualToString:leaderboardResourcePath])
    {
        @synchronized(standings)
        {
             standings = objects;
        }
    }
}    

这是映射代码:

+ (void)setMappings
{
    //Standings mapping
    RKObjectMapping* leaderboardMapping = [RKObjectMapping mappingForClass:[Leaderboard class]];
    [leaderboardMapping mapKeyPath:@"uname" toAttribute:@"uname"];
    [leaderboardMapping mapKeyPath:@"geo" toAttribute:@"geo"];
    [leaderboardMapping mapKeyPath:@"week" toAttribute:@"week"];
    [leaderboardMapping mapKeyPath:@"year" toAttribute:@"year"];
    [leaderboardMapping mapKeyPath:@"pts" toAttribute:@"pts"];  

    [[RKObjectManager sharedManager].mappingProvider addObjectMapping:leaderboardMapping];

    RKObjectRouter *router = [RKObjectManager sharedManager].router;

    // Define a default …

所以我正在阅读如何在实现API时避免在块中捕获自身？关于内存管理如何在完成块中引用self并且让我思考:以下内容是否会导致保留周期？

伪代码:

[AFnetworking requestGet:@"http://www.website.com" completionBlock:(^)(RequestObj* request, NSError* error){
      [self.tableView reloadData];
}];

忽略语法问题,self.tableView会导致保留周期吗？是否有必要做以下事情？

__weak id weakSelf = self;
[AFnetworking requestGet:@"http://www.website.com" completionBlock:(^)(RequestObj* request, NSError* error){
      [weakSelf.tableView reloadData];
}];

或者AFNetworking是否有某种记忆魔法可以阻止这种情况？

编辑Aaron Brager的礼貌

这里没有保留周期.但是如果你这样做了,在完成块中,你应该将weakSelf转换回一个强引用,这样它就不会在你的完成块中途被解除分配.

id strongSelf = weakSelf; 
[strongSelf.tableView reloadData];