Menangani peristiwa ketukan

Pilih platform: Android iOS JavaScript

Buat fitur data merespons peristiwa ketuk, dan gunakan peristiwa tersebut untuk menampilkan nilai atribut untuk fitur yang diketuk.

Terapkan gaya visual sebagai respons terhadap peristiwa ketuk.

Menangani peristiwa lapisan set data

Contoh ini menunjukkan fitur data untuk set data dengan ID YOUR_DATASET_ID, dan menerapkan fungsi delegate untuk menampilkan nilai atribut untuk fitur yang diketuk.

Dalam contoh ini, set data menampilkan taman di New York City. Untuk setiap fitur set data, yang sesuai dengan taman, set data berisi atribut bernama acres yang berisi luas permukaan taman. Untuk taman yang diketuk, tampilkan nilai atribut acres.

Swift

class SampleViewController: UIViewController {

  private lazy var mapView: GMSMapView = GMSMapView(frame: .zero, mapID: GMSMapID(identifier: "YOUR_MAP_ID"), camera: GMSCameraPosition(latitude: 40.7, longitude: -74, zoom: 12))

  // Set default styles.
  view = mapView
  let style = FeatureStyle(fill: .green.withAlphaComponent(0.5), stroke: .green, strokeWidth: 2)
  mapView.datasetFeatureLayer(of: "YOUR_DATASET_ID").style = { _ in style }
  mapView.delegate = self
}

extension SampleViewController: GMSMapViewDelegate {
  func mapView(_ mapView: GMSMapView, didTap features: [Feature], in featureLayer: FeatureLayer<Feature>, atLocation: CLLocationCoordinate2D) {
    let toast = UIAlertController(title: "Area of park", message: (features.compactMap { ($0 as? DatasetFeature)?.datasetAttributes["acres"] }).joined(separator: ", "), preferredStyle: .alert)
    present(toast, animated: true, completion: nil)
  }
}

Objective-C

@interface SampleViewController: UIViewController <GMSMapViewDelegate>
@end

@implementation SampleViewController
- (void)loadView {
    GMSMapView *mapView = [GMSMapView mapWithFrame:CGRectZero mapID:[GMSMapID mapIDWithIdentifier:@"YOUR_MAP_ID"] camera:[GMSCameraPosition cameraWithLatitude:40.7 longitude:-74 zoom:12]];
    mapView.delegete = self;

    // Set default styles.
    GMSFeatureStyle *style = [GMSFeatureStyle styleWithFillColor:[[UIColor greenColor] colorWithAlphaComponent:0.5] strokeColor:[UIColor greenColor] strokeWidth:2.0];
    [_mapView datasetFeatureLayerOfDatasetID:@"YOUR_DATASET_ID"].style = ^(GMSDatasetFeature *feature) { return style; };

    self.view = mapView;
}

- (void)mapView:(GMSMapView *)mapView didTapFeatures:(NSArray<id<GMSFeature>> *)features inFeatureLayer:(GMSFeatureLayer *)featureLayer atLocation:(CLLocationCoordinate2D)location {
  NSMutableArray<NSString *> *parkAreas = [NSMutableArray array];

  for (id<GMSFeature> feature in features) {
    if (![feature isKindOfClass:[GMSDatasetFeature class]]) { continue; }
    NSString *nameDefinedInDataset = ((GMSDatasetFeature *)feature).datasetAttributes[@"acres"];
    [parkAreas addObject:nameDefinedInDataset];
  }

  UIAlertController *toast = [UIAlertController alertControllerWithTitle:@"Area of park" message:[parkAreas componentsJoinedByString:@", "] preferredStyle:UIAlertControllerStyleAlert];
  [self presentViewController:toast animated:YES completion:nil];
}
@end