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