ios - 拉动刷新崩溃 ios 应用程序

Question

我在我的应用程序中使用拉动来刷新 Collection View ，但应用程序因错误而崩溃。

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 2 beyond bounds for empty array'

我正在使用异步队列从服务器获取数据。

以下是我从服务器获取数据并成功更新用户界面的代码:

     refreshControl = [[UIRefreshControl alloc] init];
     [refreshControl addTarget:self action:@selector(startRefresh:)
           forControlEvents:UIControlEventValueChanged];

- (void)startRefresh:(UIRefreshControl *)refreshcontrol
{
    dispatch_queue_t fetchQueue = dispatch_queue_create("fetch Queue", NULL);

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
     //webservice call which on success post notification
    });
}


- (void)onSuccess:(NSNotification *)success { //notification after success of webservice
    [storyCollectionView setHidden:NO];
    NSLog(@"fun:%s", __func__);

    dispatch_async(dispatch_get_main_queue(), ^{//in the main queue i'm ending refresing
        if ([refreshControl isRefreshing]) {
        [refreshControl endRefreshing];
        } 

    [CollectionView reloadData];// reloading collection view
    }
                   );

  }

Answer 1

我认为您应该在调用refreshcontrol.endrefreshing 后重新加载 Collection View 或 TableView 。 喜欢:-

@objc func refresh(sender:AnyObject) {
        // Code to refresh table view
        //Do all other API Calling stuff here
        refreshControl.endRefreshing()
        self.tableviewList?.reloadData()
    }

它将完美运行!! :)