使用UIRefreshControl

应用中用到UIRefreshControl。

遇到一些问题，请大神解答。

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.searchDisplayController.delegate = self;
    UIRefreshControl *refreshControl = [[UIRefreshControl alloc] init];
    [refreshControl addTarget:self action:@selector(refresh:) forControlEvents:UIControlEventValueChanged];
    [self.rearTableView addSubview:refreshControl];
}
- (void)refresh:(UIRefreshControl *)refreshControl {
    [refreshControl beginRefreshing];
    [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(endRefresh:) userInfo:nil repeats:NO];
}
- (void)endRefresh:(UIRefreshControl *)refresh
{
    [refresh endRefreshing];
}

拖拽tableView会初始化计时器，但是提前2秒。然后应用就崩溃了：

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFTimer endRefreshing]: unrecognized selector sent to instance 0x9c093c0'