Mapkit：如何在MKLocalSearch結果地標上添加註釋？

基本上我需要一種方法來對所有搜索請求所提取的「Walmarts」進行註釋。我不使用接口生成器，我只是使用這個應用程序的代碼。Mapkit：如何在MKLocalSearch結果地標上添加註釋？

MKMapView * map = [[MKMapView alloc] initWithFrame: 
        CGRectMake(0, 0, 320, 480)]; 
map.delegate = self; 
[self.view addSubview:map]; 
[super viewDidLoad]; 
// Do any additional setup after loading the view, typically from a nib. 



MKLocalSearchRequest *request = [[MKLocalSearchRequest alloc] init]; 
request.naturalLanguageQuery = @"Walmart"; 
request.region = map.region;

來源

2013-04-15 moomoo

您的初始化也需要改變 - 遵循XCode註釋所說 - 所有的mapview初始化必須在[super viewDidLoad]之後發生。 –

@moomoo - 僅供參考，如果在緩慢的網絡上工作，我已經更新了我的答案，以便在啓動新網絡之前取消先前的搜索（如果還在進行中），請進行更新。 – Rob

我建議乾脆在viewDidLoad創建的MapView：

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    MKMapView * map = [[MKMapView alloc] initWithFrame:self.view.bounds]; 
    map.delegate = self; 

    [self.view addSubview:map]; 
}

但是當用戶移動地圖，尋找Walmarts並添加註釋：

- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated 
{ 
    // if on slow network, it's useful to keep track of the previous 
    // search, and cancel it if it still exists 

    [self.previousSearch cancel]; 

    // create new search request 

    MKLocalSearchRequest *request = [[MKLocalSearchRequest alloc] init]; 
    request.naturalLanguageQuery = @"Walmart"; 
    request.region = mapView.region; 

    // initiate new search 

    MKLocalSearch *localSearch = [[MKLocalSearch alloc] initWithRequest:request]; 
    [localSearch startWithCompletionHandler:^(MKLocalSearchResponse *response, NSError *error) { 

     NSMutableArray *annotations = [NSMutableArray array]; 

     [response.mapItems enumerateObjectsUsingBlock:^(MKMapItem *item, NSUInteger idx, BOOL *stop) { 

      // if we already have an annotation for this MKMapItem, 
      // just return because you don't have to add it again 

      for (id<MKAnnotation>annotation in mapView.annotations) 
      { 
       if (annotation.coordinate.latitude == item.placemark.coordinate.latitude && 
        annotation.coordinate.longitude == item.placemark.coordinate.longitude) 
       { 
        return; 
       } 
      } 

      // otherwise, add it to our list of new annotations 
      // ideally, I'd suggest a custom annotation or MKPinAnnotation, but I want to keep this example simple 

      [annotations addObject:item.placemark]; 
     }]; 

     [mapView addAnnotations:annotations]; 
    }]; 

    // update our "previous" search, so we can cancel it if necessary 

    self.previousSearch = localSearch; 
}

顯然，此代碼示例假定您有一個weak屬性用於以前的搜索操作。（這不，嚴格來說，必要的，但如果在地圖上隨便逛逛，當你有一個緩慢的互聯網連接可能會給你更好的性能。）無論如何，該屬性將被定義如下：

@property (nonatomic, weak) MKLocalSearch *previousSearch;

還有其他可能的改進方案（如UIActivityIndicatorView或網絡活動指示符，如果正在進行搜索，可能會刪除不在地圖當前區域內的註釋等），但希望您能明白。

來源

2013-04-15 19:07:56 Rob

這裏是方法：

MKLocalSearch *localSearch = [[MKLocalSearch alloc] initWithRequest:request]; 
[self.localSearch startWithCompletionHandler:^(MKLocalSearchResponse *response, NSError *error) { 

if(error) 
{ 
     NSLog(@"localSearch startWithCompletionHandlerFailed! Error: %@", error); 
     return; 
} 
else 
{ 
     for(MKMapItem *mapItem in response.mapItems) 
     { 
      MKPinAnnotation *annotation = [[MKPinAnnotation alloc] initWithCoordinate: mapItem.placemark.location.coordinate]; 
      [map addAnnotation:annotation]; 
      NSLog(@"Name for result: = %@", mapItem.name); 
     } 
}}];

來源

2013-04-15 18:43:55

Mapkit：如何在MKLocalSearch結果地標上添加註釋？

回答

相關問題