Choroplethenkarten erstellen

Plattform auswählen: Android iOS JavaScript

Eine Choroplethenkarte (Intensitätskarte) ist eine thematische Karte, bei der Verwaltungsgebiete gemäß einem Datenwert eingefärbt bzw. schattiert werden. Mit GMSFeatureLayer können Sie den Stil einer Karte basierend auf Daten definieren, wobei jedem Verwaltungsgebiet ein numerischer Wertebereich zugeordnet ist.

Ein Diagramm mit einer Choroplethenkarte mit Grenzen

In diesem Beispiel bestehen die Daten aus einem Array von Schlüssel/Wert-Paaren, bei dem der Anzeigename eines Bundesstaates mit einem numerischen Wert für die Bevölkerung verknüpft ist.

Swift

//..

let featureLayer = mapView.featureLayer(of: FeatureType.administrativeAreaLevel1)

let populationOfStates = [
"ChIJdf5LHzR_hogR6czIUzU0VV4": 5_039_877,
"ChIJG8CuwJzfAFQRNduKqSde27w": 732673,
"ChIJaxhMy-sIK4cRcc3Bf7EnOUI": 7_276_316,
"ChIJYSc_dD-e0ocR0NLf_z5pBaQ": 3_025_891,
"ChIJPV4oX_65j4ARVW8IJ6IJUYs": 39_237_836,  // California
"ChIJt1YYm3QUQIcR_6eQSTGDVMc": 5_812_069,
"ChIJpVER8hFT5okR5XBhBVttmq4": 3_605_597,
"ChIJO9YMTXYFx4kReOgEjBItHZQ": 1_003_384,
"ChIJvypWkWV2wYgR0E7HW9MTLvc": 21_781_128,
"ChIJV4FfHcU28YgR5xBP7BC8hGY": 10_799_566,
"ChIJBeB5Twbb_3sRKIbMdNKCd0s": 1_441_553,
"ChIJ6Znkhaj_WFMRWIf3FQUwa9A": 1_900_923,
"ChIJGSZubzgtC4gRVlkRZFCCFX8": 12_671_469,
"ChIJHRv42bxQa4gRcuwyy84vEH4": 6_805_985,
"ChIJGWD48W9e7ocR2VnHV0pj78Y": 3_193_079,
"ChIJawF8cXEXo4cRXwk-S6m0wmg": 2_934_582,
"ChIJyVMZi0xzQogR_N_MxU5vH3c": 4_509_394,
"ChIJZYIRslSkIIYRA0flgTL3Vck": 4_624_047,
"ChIJ1YpTHd4dsEwR0KggZ2_MedY": 1_372_247,
"ChIJ35Dx6etNtokRsfZVdmU3r_I": 6_165_129,
"ChIJ_b9z6W1l44kRHA2DVTbQxkU": 6_984_723,
"ChIJEQTKxz2qTE0Rs8liellI3Zc": 10_050_811,
"ChIJmwt4YJpbWE0RD6L-EJvJogI": 5_707_390,
"ChIJGdRK5OQyKIYR2qbc6X8XDWI": 2_949_965,
"ChIJfeMiSNXmwIcRcr1mBFnEW7U": 6_168_187,
"ChIJ04p7LZwrQVMRGGwqz1jWcfU": 1_104_271,
"ChIJ7fwMtciNk4cRxArzDwyQJ6E": 1_963_692,
"ChIJcbTe-KEKmYARs5X8qooDR88": 3_143_991,
"ChIJ66bAnUtEs0wR64CmJa8CyNc": 1_388_992,
"ChIJn0AAnpX7wIkRjW0_-Ad70iw": 9_267_130,
"ChIJqVKY50NQGIcRup41Yxpuv0Y": 2_115_877,
"ChIJqaUj8fBLzEwRZ5UY3sHGz90": 19_835_913,
"ChIJgRo4_MQfVIgRGa4i6fUwP60": 10_551_162,
"ChIJY-nYVxKD11IRyc9egzmahA0": 774948,
"ChIJwY5NtXrpNogRFtmfnDlkzeU": 11_780_017,
"ChIJnU-ssRE5rIcRSOoKQDPPHF0": 3_986_639,
"ChIJVWqfm3xuk1QRdrgLettlTH0": 4_246_155,
"ChIJieUyHiaALYgRPbQiUEchRsI": 12_964_056,
"ChIJD9cOYhQ15IkR5wbB57wYTh4": 1_095_610,
"ChIJ49ExeWml-IgRnhcF9TKh_7k": 5_190_705,
"ChIJpTjphS1DfYcRt6SGMSnW8Ac": 895376,
"ChIJA8-XniNLYYgRVpGBpcEgPgM": 6_975_218,
"ChIJSTKCCzZwQIYRPN4IGI8c6xY": 29_527_941,
"ChIJzfkTj8drTIcRP0bXbKVK370": 3_337_975,
"ChIJ_87aSGzctEwRtGtUNnSJTSY": 645570,
"ChIJzbK8vXDWTIgRlaZGt0lBTsA": 8_642_274,
"ChIJ-bDD5__lhVQRuvNfbGh4QpQ": 7_738_692,
"ChIJRQnL1KVUSogRQzrN3mjHALs": 1_782_959,
"ChIJr-OEkw_0qFIR1kmG-LjV1fI": 5_895_908,
"ChIJaS7hSDTiXocRLzh90nkisCY": 578803,  // Wyoming
]

featureLayer.style = { feature in
  FeatureStyle(
    fill: populationOfStates[feature.placeID].map {
      UIColor(
        hue: log(CGFloat($0) / 5e5) / 7.5,
        saturation: 1,
        brightness: 0.75,
        alpha: 0.5)
    } ?? nil,
    stroke: nil,
    strokeWidth: 0
  )
}

self.view = mapView

Objective-C

//..

GMSFeatureLayer<GMSPlaceFeature *> *featureLayer =
    [mapView featureLayerOfFeatureType:GMSFeatureTypeAdministrativeAreaLevel1];

NSDictionary<NSString *, NSNumber *> *populationOfStates = @{
  @"ChIJdf5LHzR_hogR6czIUzU0VV4" : @(5039877),
  @"ChIJG8CuwJzfAFQRNduKqSde27w" : @(732673),
  @"ChIJaxhMy-sIK4cRcc3Bf7EnOUI" : @(7276316),
  @"ChIJYSc_dD-e0ocR0NLf_z5pBaQ" : @(3025891),
  @"ChIJPV4oX_65j4ARVW8IJ6IJUYs" : @(39237836),  // California
  @"ChIJt1YYm3QUQIcR_6eQSTGDVMc" : @(5812069),
  @"ChIJpVER8hFT5okR5XBhBVttmq4" : @(3605597),
  @"ChIJO9YMTXYFx4kReOgEjBItHZQ" : @(1003384),
  @"ChIJvypWkWV2wYgR0E7HW9MTLvc" : @(21781128),
  @"ChIJV4FfHcU28YgR5xBP7BC8hGY" : @(10799566),
  @"ChIJBeB5Twbb_3sRKIbMdNKCd0s" : @(1441553),
  @"ChIJ6Znkhaj_WFMRWIf3FQUwa9A" : @(1900923),
  @"ChIJGSZubzgtC4gRVlkRZFCCFX8" : @(12671469),
  @"ChIJHRv42bxQa4gRcuwyy84vEH4" : @(6805985),
  @"ChIJGWD48W9e7ocR2VnHV0pj78Y" : @(3193079),
  @"ChIJawF8cXEXo4cRXwk-S6m0wmg" : @(2934582),
  @"ChIJyVMZi0xzQogR_N_MxU5vH3c" : @(4509394),
  @"ChIJZYIRslSkIIYRA0flgTL3Vck" : @(4624047),
  @"ChIJ1YpTHd4dsEwR0KggZ2_MedY" : @(1372247),
  @"ChIJ35Dx6etNtokRsfZVdmU3r_I" : @(6165129),
  @"ChIJ_b9z6W1l44kRHA2DVTbQxkU" : @(6984723),
  @"ChIJEQTKxz2qTE0Rs8liellI3Zc" : @(10050811),
  @"ChIJmwt4YJpbWE0RD6L-EJvJogI" : @(5707390),
  @"ChIJGdRK5OQyKIYR2qbc6X8XDWI" : @(2949965),
  @"ChIJfeMiSNXmwIcRcr1mBFnEW7U" : @(6168187),
  @"ChIJ04p7LZwrQVMRGGwqz1jWcfU" : @(1104271),
  @"ChIJ7fwMtciNk4cRxArzDwyQJ6E" : @(1963692),
  @"ChIJcbTe-KEKmYARs5X8qooDR88" : @(3143991),
  @"ChIJ66bAnUtEs0wR64CmJa8CyNc" : @(1388992),
  @"ChIJn0AAnpX7wIkRjW0_-Ad70iw" : @(9267130),
  @"ChIJqVKY50NQGIcRup41Yxpuv0Y" : @(2115877),
  @"ChIJqaUj8fBLzEwRZ5UY3sHGz90" : @(19835913),
  @"ChIJgRo4_MQfVIgRGa4i6fUwP60" : @(10551162),
  @"ChIJY-nYVxKD11IRyc9egzmahA0" : @(774948),
  @"ChIJwY5NtXrpNogRFtmfnDlkzeU" : @(11780017),
  @"ChIJnU-ssRE5rIcRSOoKQDPPHF0" : @(3986639),
  @"ChIJVWqfm3xuk1QRdrgLettlTH0" : @(4246155),
  @"ChIJieUyHiaALYgRPbQiUEchRsI" : @(12964056),
  @"ChIJD9cOYhQ15IkR5wbB57wYTh4" : @(1095610),
  @"ChIJ49ExeWml-IgRnhcF9TKh_7k" : @(5190705),
  @"ChIJpTjphS1DfYcRt6SGMSnW8Ac" : @(895376),
  @"ChIJA8-XniNLYYgRVpGBpcEgPgM" : @(6975218),
  @"ChIJSTKCCzZwQIYRPN4IGI8c6xY" : @(29527941),
  @"ChIJzfkTj8drTIcRP0bXbKVK370" : @(3337975),
  @"ChIJ_87aSGzctEwRtGtUNnSJTSY" : @(645570),
  @"ChIJzbK8vXDWTIgRlaZGt0lBTsA" : @(8642274),
  @"ChIJ-bDD5__lhVQRuvNfbGh4QpQ" : @(7738692),
  @"ChIJRQnL1KVUSogRQzrN3mjHALs" : @(1782959),
  @"ChIJr-OEkw_0qFIR1kmG-LjV1fI" : @(5895908),
  @"ChIJaS7hSDTiXocRLzh90nkisCY" : @(578803),  // Wyoming
};

featureLayer.style = ^(GMSPlaceFeature *feature) {
  NSNumber *population = populationOfStates[feature.placeID];
  UIColor *fillColor = population ? [UIColor colorWithHue:(log(population.doubleValue / 5e5) / 7.5) saturation:1 brightness:0.5 alpha:0.5] : nil;
  return [GMSFeatureStyle styleWithFillColor:fillColor strokeColor:nil strokeWidth:0.0];
};

self.view = mapView;