【IOS】异步调用--- 简单使用记录

/××
  ×实现功能：店铺被删除后，先显示提示toast.然后，页面休眠5秒后，再返回到店铺列表页面。
×/

- (void)processDeleteShopError
{
    _isLoadingData = NO;
    [_tableView refreshScrollViewDataSourceDidFinishedLoading:_tableView];
    [self showToast:@"店铺被删除,返回店铺列表页面刷新数据"];
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, );
    dispatch_async(queue, ^{
        [NSThread sleepForTimeInterval:5];
        dispatch_async(dispatch_get_main_queue(), ^{
            [self backToPreController];
        });
    });
}

- (void)backToPreController
{
    [_shopEditDelegate shopDeleted:_shop];
    [self.navigationController popToRootViewControllerAnimated:YES];
}

注意和以下代码比较，其效果不一样。

- (void)processDeleteShopError
{
    _isLoadingData = NO;
    [_tableView refreshScrollViewDataSourceDidFinishedLoading:_tableView];
    [self showToast:@"店铺被删除,返回店铺列表页面刷新数据"];

    [[NSThread alloc]performSelector:@selector(backToPreController) withObject:nil afterDelay:];
}

- (void) backToPreController
{
    [_shopEditDelegate shopDeleted:_shop];
    [self.navigationController popToRootViewControllerAnimated:YES];
}