iPhone iOS5 CLGeocoder 如何对一大组(200)地址进行地理编码？

Question

我有一大组大约 200 个地址，我需要知道它们的纬度和经度。我创建了一个解析地址的方法，现在我尝试使用 CLGeocoder 获取这些地址的坐标。

我目前的方法是并行创建地理编码器并让它们发挥作用。我注意到他们每个人似乎都有一个单独的线程。 (所以我一次看到多达 100 个线程)。

我遇到的问题是在某些时候(大约 50 个地址之后)，地理编码停止返回任何地点标记，并且

NSLog(@"Address not recognized: *%@*",[htc objectForKey:kAddressKey]);

被调用。这是对多个线程的限制还是内置的 CLGeocoder 限制？会不会是我没有正确清理地理编码器，需要某种自动释放语句 (ARC)？

-(void)geocodeArray:(NSMutableArray*)数组 {

    NSMutableDictionary* htc = nil;
    objectsToGeocode = array.count;

    NSDictionary *htcDictionary =nil;
     for (int i = 0; i<array.count;i++) {
         htcDictionary = [array objectAtIndex:i];

        //create an updated dictionary that would hold the reverse geocoding location
        htc = [[NSMutableDictionary alloc] initWithDictionary:htcDictionary];
        NSLog(@"geocoding: %@",[htc objectForKey:kAddressKey]);

        CLGeocoder* geoCoder = [[CLGeocoder alloc] init];
        [geoCoder geocodeAddressString:[htc objectForKey:kAddressKey] completionHandler:^(NSArray *placemarks, NSError *error) {

            if(placemarks.count>0)
            {
                NSLog(@"Found placemarks for %@",[htc objectForKey:kAddressKey]);
                CLPlacemark* placemark =  [placemarks objectAtIndex:0];
                MyLocation *annotation = [[MyLocation alloc]
                                          initWithName:[htcDictionary objectForKey:kNameKey]
                                          address:[htcDictionary objectForKey:kAddressKey]
                                          coordinate:placemark.location.coordinate] ;
                annotation.faxNumber = [htc objectForKey:kFaxKey];
                annotation.phoneNumber = [htc objectForKey:kPhoneKey];
                annotation.website = [htc objectForKey:kWebsiteKey];
                annotation.type = [htc objectForKey:kFacilityTypeKey];
                [_mapView addAnnotation:annotation];  


                double placemarkToUserDistance = [self._mapView.userLocation.location distanceFromLocation:placemark.location] ;
                //convert distance to miles
                placemarkToUserDistance =placemarkToUserDistance/ 1000/ kKilometersPerMile;

                [htc setObject:[NSNumber numberWithDouble:placemarkToUserDistance] forKey:kDistanceToUserKey];
                [htc setObject:[NSNumber numberWithDouble:placemark.location.coordinate.latitude] forKey:kLatitudeKey];
                 [htc setObject:[NSNumber numberWithDouble:placemark.location.coordinate.longitude] forKey:kLongitudeKey];
                NSAssert([htc objectForKey:kLatitudeKey]!=nil,@"kLatitudeKey is not saved!");
                NSAssert([htc objectForKey:kLongitudeKey]!=nil,@"kLongitudeKey is not saved!");

            }else {
                NSLog(@"Address not recognized: *%@*",[htc objectForKey:kAddressKey]);
            }


            [self.dataSource addObject:htc];

            if(++geocodingCount >=objectsToGeocode){
                NSLog(@"%@",self.dataSource);
                    [self saveGeocoding];

            }

        } ];


        //        [temp addObject:htcDictionary];
    }

}

为了测试这是否是一个线程问题，我创建了这个方法，它将我的大型数据集拆分为 5 个数组，并尝试以 block 的形式对它们进行地理编码。我注意到第一个请求以及第二个请求的一部分通过了。但是一旦达到 (~50) 的魔数(Magic Number)，地理编码就会停止。

对可能发生的事情有什么想法吗？ 这是 Apple 对地理编码操作数量施加的限制吗？我应该增加请求之间的延迟还是尝试分别运行该应用 5 次并手动拼凑结果？

-(void)geocodeDatasource
{

        //I'm trying to build a file with coordinates of addresses and include it with the app
        geocodingCount = 0;
        self.dataSource = [[NSMutableArray alloc] initWithCapacity:self.arrayForGeocodingInitialJSON.count+5];
        haveToEmailInitialResults = YES;


    //attempt to geocode in batches

     float numberOfArrays = 5.0;
    NSMutableArray* array1 = [[NSMutableArray alloc] initWithCapacity:arrayForGeocodingInitialJSON.count/numberOfArrays];
    NSMutableArray* array2 = [[NSMutableArray alloc] initWithCapacity:arrayForGeocodingInitialJSON.count/numberOfArrays];
    NSMutableArray* array3 = [[NSMutableArray alloc] initWithCapacity:arrayForGeocodingInitialJSON.count/numberOfArrays];
    NSMutableArray* array4 = [[NSMutableArray alloc] initWithCapacity:arrayForGeocodingInitialJSON.count/numberOfArrays];
    NSMutableArray* array5 = [[NSMutableArray alloc] initWithCapacity:arrayForGeocodingInitialJSON.count/numberOfArrays];

    for(int i = 0 ;i<arrayForGeocodingInitialJSON.count;i++)
    {
        id object = [arrayForGeocodingInitialJSON objectAtIndex:i];
        if(i<arrayForGeocodingInitialJSON.count*(1/numberOfArrays))
        {
            [array1 addObject:object];
        }else if(i>=arrayForGeocodingInitialJSON.count/numberOfArrays && i<arrayForGeocodingInitialJSON.count*(2/numberOfArrays))
        {
            [array2 addObject:object];
        }else if(i>=arrayForGeocodingInitialJSON.count*(2/numberOfArrays) && i<arrayForGeocodingInitialJSON.count*(3/numberOfArrays))
        {
            [array3 addObject:object];
        }else if(i>=arrayForGeocodingInitialJSON.count*(3/numberOfArrays) && i<arrayForGeocodingInitialJSON.count*(4/numberOfArrays))
        {
            [array4 addObject:object];
        }else if(i>=arrayForGeocodingInitialJSON.count*(4/numberOfArrays) && i<arrayForGeocodingInitialJSON.count)
        {
            [array5 addObject:object];
        }



    }

    //simple delays eliminate the need for extra variables and notifications
        [self geocodeArray:array2];

        [self performSelector:@selector(geocodeArray:) withObject:array1 afterDelay:15];
        [self performSelector:@selector(geocodeArray:) withObject:array3 afterDelay:30];
        [self performSelector:@selector(geocodeArray:) withObject:array4 afterDelay:45];
        [self performSelector:@selector(geocodeArray:) withObject:array5 afterDelay:45];
}

谢谢!

Answer 1

您无法立即对大型集合进行地理编码。 iOS 会扼杀你。我看到 iOS 限制您一次只能进行 50 个地理编码，“时间”因素未知。

我遇到过类似的问题，但由于我只需要按顺序向用户呈现地理编码数据，这需要时间，所以我对所有地理编码进行了排队。

实际上，我对 25 个数据 block 进行了地理编码 - 一次向用户显示 1 个结果，每个结果之间的间隔大约为半秒。当我要显示的内容少于 4 个时，我将对接下来的 25 个进行地理编码。这将一直持续到对所有内容进行地理编码(或者在我的情况下，无限期)。

如果您需要一次对所有内容进行地理编码，则需要将您的地理编码与每个 block 之间的延迟链接在一起，并显示某种忙碌指示器，直到完成为止。大量地理编码可能需要一段时间。