Tạo bản đồ chuyên đề

Chọn nền tảng: Android iOS JavaScript

Bản đồ dạng vùng là một loại bản đồ chuyên đề, trong đó các khu vực hành chính được tô màu hoặc tô bóng theo một giá trị dữ liệu. Bạn có thể sử dụng GMSFeatureLayer để tạo kiểu cho bản đồ dựa trên dữ liệu, trong đó mỗi khu vực hành chính được liên kết với một dải giá trị số.

Sơ đồ thể hiện bản đồ vùng biên dạng choropleth

Trong ví dụ này, dữ liệu bao gồm một mảng các cặp khoá-giá trị, khớp với tên hiển thị của mỗi tiểu bang với một giá trị dân số dạng số.

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;