ios - GMSGeocoder iOS SDK - 没有收到反向地理编码的回调

Question

我正在滚动浏览 Assets 组中的每个 Assets ，并尝试从 Google Maps sdk 1.9.1 中使用的图像的现有数据中检索位置。这是我写的代码

-(NSString *) doRevGeoCodingForLocationWithLat:(double)lat AndLon:(double)lon {
__block NSString *finalAddress = nil;
GMSGeocoder *sharedInstance = [[GMSGeocoder alloc] init];
if (sharedInstance) {
    dispatch_semaphore_t sema = dispatch_semaphore_create(0);
    CLLocationCoordinate2D coordinate = CLLocationCoordinate2DMake(lat, lon);
    GMSReverseGeocodeCallback handler = ^(GMSReverseGeocodeResponse *response, NSError *error) {
        if (!error && response) {
            NSLog(@"Mil gaya");
            GMSAddress *firstAddress = [response firstResult];
            NSString *formattedAddress = nil;
            if (firstAddress.locality)
                formattedAddress = [NSString stringWithString:firstAddress.locality];

            if (firstAddress.administrativeArea) {
                if (formattedAddress)
                    formattedAddress = [formattedAddress stringByAppendingFormat:@", %@", firstAddress.administrativeArea];
                else
                    formattedAddress = [NSString stringWithString:firstAddress.administrativeArea];
            }
            if (firstAddress.country) {
                if (formattedAddress)
                    formattedAddress = [formattedAddress stringByAppendingFormat:@", %@", firstAddress.country];
                else
                    formattedAddress = [NSString stringWithString:firstAddress.country];
            }
            if (formattedAddress) {
                finalAddress = [NSString stringWithString:formattedAddress];
            }
        }
        dispatch_semaphore_signal(sema);
    };

    [sharedInstance reverseGeocodeCoordinate:coordinate completionHandler:handler];
    dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
}
return finalAddress;
}

问题是 completionHandler 回调从不从 SDK 回调。我已经设置了 google APIs 控制台，并且与 sdk 捆绑在一起的演示应用程序运行良好。

我从文档中了解到在应用程序的主队列上调用了 completionHandler。问题是否会发生，因为此操作是在通过 Assets 枚举的并发队列上发生的？任何帮助将不胜感激。

Answer 1

Arc 正在立即释放您忠实的 Geocoder 变量，并且无法进行任何异步调用。

作为测试/hack，将 sharedInstance 设置为全局，以便保留它。