Batch Geocode MKLocalSearchResponse

Question

我有一个搜索设置，在UITableVIew中显示MKLocalSearchRequest的响应

我想从每个搜索的响应中清理所有响应。这是我到目前为止完成这个任务的机会，灵感来自这篇文章在地图上的多个位置(使用MKMapItem和CLGeocoder)

这是我的代码。

@interface ViewController () <UISearchBarDelegate,UISearchDisplayDelegate,UITextFieldDelegate>
@property (nonatomic, strong) UISearchDisplayController *searchController;
@property (nonatomic, strong) UISearchBar *searchBar;
@property (nonatomic, strong) MKLocalSearch *localSearch;
@property (nonatomic, strong) MKLocalSearchResponse *localSearchResponse;
@property (nonatomic, strong) NSArray *dirtyResponseArray;
@property (nonatomic, strong) NSMutableArray *geocodedResultsArray;
@end
@implementation ViewController
-(void)startSearch:(NSString *)searchString
{
    if (self.localSearch.searching)
        [self.localSearch cancel];
    MKLocalSearchRequest *request = [[MKLocalSearchRequest alloc] init];
    request.naturalLanguageQuery = searchString;
    request.region = MKCoordinateRegionMake(self.currentLocation.coordinate, self.mapView.region.span);
    MKLocalSearchCompletionHandler completionHandler = ^(MKLocalSearchResponse *response, NSError *error){
        if (error != nil) return;
        else {
            self.dirtyResponseArray = response.mapItems;                
            [self operation];
            [self.searchController.searchResultsTableView reloadData];
            [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
        }
        [self.searchDisplayController.searchResultsTableView reloadData];
    };
    if (self.localSearch != nil)
        self.localSearch = nil;
    self.localSearch = [[MKLocalSearch alloc] initWithRequest:request];
    [self.localSearch startWithCompletionHandler:completionHandler];
}
-(void)operation
{
    CLGeocoder *geocoder = [[CLGeocoder alloc]init];
    NSOperationQueue *queue = [[NSOperationQueue alloc] init];
    NSOperation *finalCompletionOperation = [NSBlockOperation blockOperationWithBlock:^{
        [MKMapItem openMapsWithItems:self.geocodedResultsArray launchOptions:nil];
        NSLog(@"Local Search Response To use in tableview =================== %@", self.geocodedResultsArray);
    }];
    NSOperation *previousCompletionHandler = nil;
    //Issue is probably right here. How should I handle the MKMapItem in the array?
    //NSString *address = [self.dirtyResponseArray valueForKey:@"address"][@"formattedAddress"]; ??
    for (NSString *address in self.dirtyResponseArray) {
        NSBlockOperation *geocodeRequest = [[NSBlockOperation alloc] init];
        if (previousCompletionHandler) [geocodeRequest addDependency:previousCompletionHandler];
        NSBlockOperation *geocodeCompletionHandler = [[NSBlockOperation alloc] init];
        [finalCompletionOperation addDependency:geocodeCompletionHandler];
        [geocodeRequest addExecutionBlock:^{ [geocoder geocodeAddressString:address 
                        completionHandler:^(NSArray *placemarks, NSError *error) 
        {
                [geocodeCompletionHandler addExecutionBlock:^{
                    if (error) NSLog(@"%@", error);
                    else if ([placemarks count] > 0)
                    {
                        CLPlacemark *geocodedPlacemark = [placemarks objectAtIndex:0];
                        MKPlacemark *placemark = [[MKPlacemark alloc] initWithCoordinate:geocodedPlacemark.location.coordinate
                                                                       addressDictionary:geocodedPlacemark.addressDictionary];
                        MKMapItem *mapItem = [[MKMapItem alloc] initWithPlacemark:placemark];
                        [mapItem setName:geocodedPlacemark.name];
                        [self.geocodedResultsArray addObject:mapItem];
                    }
                }];
                [queue addOperation:geocodeCompletionHandler];
            }];
        }];
        [queue addOperation:geocodeRequest];
        previousCompletionHandler = geocodeCompletionHandler;
    }
    [queue addOperation:finalCompletionOperation];
}
@end

我不确定如何处理每个MKMapItem。现在它抛出这个错误

 -[MKMapItem length]: unrecognized selector sent to instance 0x7f813c9c6200

Answer 1

在另一个问题中引用的CLGeocoder方法geocodeAddressString是为对地址进行地理编码而设计的。

但是您在特定区域内执行MKLocalSearch，它返回已经进行地理编码的MKMapItem对象。因此，您可以从代码示例中完全删除geocodeAddressString代码。

事实上，这解释了异常的来源，您正在使用MKLocalSearch返回的MKMapItem，并试图将其用作CLGeocoder方法geocodeAddressString的搜索字符串参数(仅用于查找地址的字符串表示)。

最重要的是，在地图应用程序中进行本地搜索并显示结果比你上面想象的要容易得多。你所需要做的就是:

MKLocalSearchRequest *request = [[MKLocalSearchRequest alloc] init];
request.naturalLanguageQuery = searchString;
request.region = region;
MKLocalSearch *search = [[MKLocalSearch alloc] initWithRequest:request];
[search startWithCompletionHandler:^(MKLocalSearchResponse *response, NSError *error) {
    [MKMapItem openMapsWithItems:response.mapItems launchOptions:nil];
}];

或者，如果你想在你自己的MKMapView上显示它，你可以这样做

MKLocalSearchRequest *request = [[MKLocalSearchRequest alloc] init];
request.naturalLanguageQuery = searchString;
request.region = region;
MKLocalSearch *search = [[MKLocalSearch alloc] initWithRequest:request];
[search startWithCompletionHandler:^(MKLocalSearchResponse *response, NSError *error) {
    for (MKMapItem *item in response.mapItems) {
        [self.mapView addAnnotation:item.placemark];
    }
}];

实际上，在后一个示例中，您将在自己的地图视图上显示结果，您可能会创建自己的自定义注释类，以便在viewForAnnotation方法中更好地控制注释视图的呈现。但希望这说明了主要观察结果，即当使用MKLocalSearch时，您不应该使用CLGeocoder方法geocodeAddressString。