Bản đồ choropleth là một loại bản đồ theo chủ đề trong đó các khu vực hành chính
được tô màu hoặc tô bóng theo giá trị dữ liệu. Bạn có thể sử dụng
google.maps.FeatureStyleFunction
để tạo kiểu cho bản đồ dựa trên một tập dữ liệu nơi từng khu vực hành chính được liên kết
có một dải giá trị số. Bản đồ mẫu sau đây thể hiện bản đồ choropleth
mô tả dữ liệu dân số của tiểu bang cho Hoa Kỳ.
Trong ví dụ này, dữ liệu bao gồm một mảng các cặp khoá-giá trị, khớp với
tên hiển thị của mỗi trạng thái bằng giá trị dân số dạng số. Chiến lược phát hành đĩa đơn
maps.FeatureStyleFunction tô màu có điều kiện cho từng khu vực dựa trên
các giá trị trong mảng.
TypeScript
featureLayer.style = featureStyleFunctionOptions => {
const placeFeature = featureStyleFunctionOptions.feature as google.maps.PlaceFeature;
const population = states[placeFeature.placeId];
let fillColor;
// Specify colors using any of the following:
// * Named ('green')
// * Hexadecimal ('#FF0000')
// * RGB ('rgb(0, 0, 255)')
// * HSL ('hsl(60, 100%, 50%)')
if (population < 2000000) {
fillColor = 'green'
} else if (population < 5000000) {
fillColor = 'red'
} else if (population < 10000000) {
fillColor = 'blue'
} else if (population < 40000000) {
fillColor = 'yellow'
}
return {
fillColor,
fillOpacity: 0.5
}
}
JavaScript
featureLayer.style = (featureStyleFunctionOptions) => {
const placeFeature = featureStyleFunctionOptions.feature;
const population = states[placeFeature.placeId];
let fillColor;
// Specify colors using any of the following:
// * Named ('green')
// * Hexadecimal ('#FF0000')
// * RGB ('rgb(0, 0, 255)')
// * HSL ('hsl(60, 100%, 50%)')
if (population < 2000000) {
fillColor = "green";
} else if (population < 5000000) {
fillColor = "red";
} else if (population < 10000000) {
fillColor = "blue";
} else if (population < 40000000) {
fillColor = "yellow";
}
return {
fillColor,
fillOpacity: 0.5,
};
};
Mã mẫu hoàn chỉnh
TypeScript
async function initMap() {
// Request needed libraries.
const { Map } = await google.maps.importLibrary("maps") as google.maps.MapsLibrary;
const map = new Map(document.getElementById('map') as HTMLElement, {
center: { lat: 40.76, lng: -101.64 },
zoom: 5,
// In the cloud console, configure this Map ID with a style that enables the
// "Administrative Area Level 1" feature layer.
mapId: '7ba16be0c9375fa7',
});
const featureLayer = map.getFeatureLayer(google.maps.FeatureType.ADMINISTRATIVE_AREA_LEVEL_1);
featureLayer.style = featureStyleFunctionOptions => {
const placeFeature = featureStyleFunctionOptions.feature as google.maps.PlaceFeature;
const population = states[placeFeature.placeId];
let fillColor;
// Specify colors using any of the following:
// * Named ('green')
// * Hexadecimal ('#FF0000')
// * RGB ('rgb(0, 0, 255)')
// * HSL ('hsl(60, 100%, 50%)')
if (population < 2000000) {
fillColor = 'green'
} else if (population < 5000000) {
fillColor = 'red'
} else if (population < 10000000) {
fillColor = 'blue'
} else if (population < 40000000) {
fillColor = 'yellow'
}
return {
fillColor,
fillOpacity: 0.5
}
}
// Population data by state.
const states = {
"ChIJdf5LHzR_hogR6czIUzU0VV4": 5039877, // Alabama
"ChIJG8CuwJzfAFQRNduKqSde27w": 732673, // Alaska
"ChIJaxhMy-sIK4cRcc3Bf7EnOUI": 7276316, // Arizona
"ChIJYSc_dD-e0ocR0NLf_z5pBaQ": 3025891, // Arkansas
"ChIJPV4oX_65j4ARVW8IJ6IJUYs": 39237836, // California
"ChIJt1YYm3QUQIcR_6eQSTGDVMc": 5812069, // Colorado
"ChIJpVER8hFT5okR5XBhBVttmq4": 3605597, // Connecticut
"ChIJO9YMTXYFx4kReOgEjBItHZQ": 1003384, // Delaware
"ChIJvypWkWV2wYgR0E7HW9MTLvc": 21781128, // Florida
"ChIJV4FfHcU28YgR5xBP7BC8hGY": 10799566, // Georgia
"ChIJBeB5Twbb_3sRKIbMdNKCd0s": 1441553, // Hawaii
"ChIJ6Znkhaj_WFMRWIf3FQUwa9A": 1900923, // Idaho
"ChIJGSZubzgtC4gRVlkRZFCCFX8": 12671469, // Illinois
"ChIJHRv42bxQa4gRcuwyy84vEH4": 6805985, // Indiana
"ChIJGWD48W9e7ocR2VnHV0pj78Y": 3193079, // Iowa
"ChIJawF8cXEXo4cRXwk-S6m0wmg": 2934582, // Kansas
"ChIJyVMZi0xzQogR_N_MxU5vH3c": 4509394, // Kentucky
"ChIJZYIRslSkIIYRA0flgTL3Vck": 4624047, // Louisiana
"ChIJ1YpTHd4dsEwR0KggZ2_MedY": 1372247, // Maine
"ChIJ35Dx6etNtokRsfZVdmU3r_I": 6165129, // Maryland
"ChIJ_b9z6W1l44kRHA2DVTbQxkU": 6984723, // Massachussetts
"ChIJEQTKxz2qTE0Rs8liellI3Zc": 10050811, // Michigan
"ChIJmwt4YJpbWE0RD6L-EJvJogI": 5707390, // Minnesota
"ChIJGdRK5OQyKIYR2qbc6X8XDWI": 2949965, // Mississippi
"ChIJfeMiSNXmwIcRcr1mBFnEW7U": 6168187, // Misssouri
"ChIJ04p7LZwrQVMRGGwqz1jWcfU": 1104271, // Montana
"ChIJ7fwMtciNk4cRxArzDwyQJ6E": 1963692, // Nebraska
"ChIJcbTe-KEKmYARs5X8qooDR88": 3143991, // Nevada
"ChIJ66bAnUtEs0wR64CmJa8CyNc": 1388992, // New Hampshire
"ChIJn0AAnpX7wIkRjW0_-Ad70iw": 9267130, // New Jersey
"ChIJqVKY50NQGIcRup41Yxpuv0Y": 2115877, // New Mexico
"ChIJqaUj8fBLzEwRZ5UY3sHGz90": 19835913, // New York
"ChIJgRo4_MQfVIgRGa4i6fUwP60": 10551162, // North Carolina
"ChIJY-nYVxKD11IRyc9egzmahA0": 774948, // North Dakota
"ChIJwY5NtXrpNogRFtmfnDlkzeU": 11780017, // Ohio
"ChIJnU-ssRE5rIcRSOoKQDPPHF0": 3986639, // Oklahoma
"ChIJVWqfm3xuk1QRdrgLettlTH0": 4246155, // Oregon
"ChIJieUyHiaALYgRPbQiUEchRsI": 12964056, // Pennsylvania
"ChIJD9cOYhQ15IkR5wbB57wYTh4": 1095610, // Rhode Island
"ChIJ49ExeWml-IgRnhcF9TKh_7k": 5190705, // South Carolina
"ChIJpTjphS1DfYcRt6SGMSnW8Ac": 895376, // South Dakota
"ChIJA8-XniNLYYgRVpGBpcEgPgM": 6975218, // Tennessee
"ChIJSTKCCzZwQIYRPN4IGI8c6xY": 29527941, // Texas
"ChIJzfkTj8drTIcRP0bXbKVK370": 3337975, // Utah
"ChIJ_87aSGzctEwRtGtUNnSJTSY": 645570, // Vermont
"ChIJzbK8vXDWTIgRlaZGt0lBTsA": 8642274, // Virginia
"ChIJ-bDD5__lhVQRuvNfbGh4QpQ": 7738692, // Washington
"ChIJRQnL1KVUSogRQzrN3mjHALs": 1782959, // West Virginia
"ChIJr-OEkw_0qFIR1kmG-LjV1fI": 5895908, // Wisconsin
"ChIJaS7hSDTiXocRLzh90nkisCY": 578803, // Wyoming
};
}
initMap();
JavaScript
async function initMap() {
// Request needed libraries.
const { Map } = await google.maps.importLibrary("maps");
const map = new Map(document.getElementById("map"), {
center: { lat: 40.76, lng: -101.64 },
zoom: 5,
// In the cloud console, configure this Map ID with a style that enables the
// "Administrative Area Level 1" feature layer.
mapId: "7ba16be0c9375fa7",
});
const featureLayer = map.getFeatureLayer(
google.maps.FeatureType.ADMINISTRATIVE_AREA_LEVEL_1,
);
featureLayer.style = (featureStyleFunctionOptions) => {
const placeFeature = featureStyleFunctionOptions.feature;
const population = states[placeFeature.placeId];
let fillColor;
// Specify colors using any of the following:
// * Named ('green')
// * Hexadecimal ('#FF0000')
// * RGB ('rgb(0, 0, 255)')
// * HSL ('hsl(60, 100%, 50%)')
if (population < 2000000) {
fillColor = "green";
} else if (population < 5000000) {
fillColor = "red";
} else if (population < 10000000) {
fillColor = "blue";
} else if (population < 40000000) {
fillColor = "yellow";
}
return {
fillColor,
fillOpacity: 0.5,
};
};
// Population data by state.
const states = {
"ChIJdf5LHzR_hogR6czIUzU0VV4": 5039877, // Alabama
"ChIJG8CuwJzfAFQRNduKqSde27w": 732673, // Alaska
"ChIJaxhMy-sIK4cRcc3Bf7EnOUI": 7276316, // Arizona
"ChIJYSc_dD-e0ocR0NLf_z5pBaQ": 3025891, // Arkansas
"ChIJPV4oX_65j4ARVW8IJ6IJUYs": 39237836, // California
"ChIJt1YYm3QUQIcR_6eQSTGDVMc": 5812069, // Colorado
"ChIJpVER8hFT5okR5XBhBVttmq4": 3605597, // Connecticut
"ChIJO9YMTXYFx4kReOgEjBItHZQ": 1003384, // Delaware
"ChIJvypWkWV2wYgR0E7HW9MTLvc": 21781128, // Florida
"ChIJV4FfHcU28YgR5xBP7BC8hGY": 10799566, // Georgia
"ChIJBeB5Twbb_3sRKIbMdNKCd0s": 1441553, // Hawaii
"ChIJ6Znkhaj_WFMRWIf3FQUwa9A": 1900923, // Idaho
"ChIJGSZubzgtC4gRVlkRZFCCFX8": 12671469, // Illinois
"ChIJHRv42bxQa4gRcuwyy84vEH4": 6805985, // Indiana
"ChIJGWD48W9e7ocR2VnHV0pj78Y": 3193079, // Iowa
"ChIJawF8cXEXo4cRXwk-S6m0wmg": 2934582, // Kansas
"ChIJyVMZi0xzQogR_N_MxU5vH3c": 4509394, // Kentucky
"ChIJZYIRslSkIIYRA0flgTL3Vck": 4624047, // Louisiana
"ChIJ1YpTHd4dsEwR0KggZ2_MedY": 1372247, // Maine
"ChIJ35Dx6etNtokRsfZVdmU3r_I": 6165129, // Maryland
"ChIJ_b9z6W1l44kRHA2DVTbQxkU": 6984723, // Massachussetts
"ChIJEQTKxz2qTE0Rs8liellI3Zc": 10050811, // Michigan
"ChIJmwt4YJpbWE0RD6L-EJvJogI": 5707390, // Minnesota
"ChIJGdRK5OQyKIYR2qbc6X8XDWI": 2949965, // Mississippi
"ChIJfeMiSNXmwIcRcr1mBFnEW7U": 6168187, // Misssouri
"ChIJ04p7LZwrQVMRGGwqz1jWcfU": 1104271, // Montana
"ChIJ7fwMtciNk4cRxArzDwyQJ6E": 1963692, // Nebraska
"ChIJcbTe-KEKmYARs5X8qooDR88": 3143991, // Nevada
"ChIJ66bAnUtEs0wR64CmJa8CyNc": 1388992, // New Hampshire
"ChIJn0AAnpX7wIkRjW0_-Ad70iw": 9267130, // New Jersey
"ChIJqVKY50NQGIcRup41Yxpuv0Y": 2115877, // New Mexico
"ChIJqaUj8fBLzEwRZ5UY3sHGz90": 19835913, // New York
"ChIJgRo4_MQfVIgRGa4i6fUwP60": 10551162, // North Carolina
"ChIJY-nYVxKD11IRyc9egzmahA0": 774948, // North Dakota
"ChIJwY5NtXrpNogRFtmfnDlkzeU": 11780017, // Ohio
"ChIJnU-ssRE5rIcRSOoKQDPPHF0": 3986639, // Oklahoma
"ChIJVWqfm3xuk1QRdrgLettlTH0": 4246155, // Oregon
"ChIJieUyHiaALYgRPbQiUEchRsI": 12964056, // Pennsylvania
"ChIJD9cOYhQ15IkR5wbB57wYTh4": 1095610, // Rhode Island
"ChIJ49ExeWml-IgRnhcF9TKh_7k": 5190705, // South Carolina
"ChIJpTjphS1DfYcRt6SGMSnW8Ac": 895376, // South Dakota
"ChIJA8-XniNLYYgRVpGBpcEgPgM": 6975218, // Tennessee
"ChIJSTKCCzZwQIYRPN4IGI8c6xY": 29527941, // Texas
"ChIJzfkTj8drTIcRP0bXbKVK370": 3337975, // Utah
"ChIJ_87aSGzctEwRtGtUNnSJTSY": 645570, // Vermont
"ChIJzbK8vXDWTIgRlaZGt0lBTsA": 8642274, // Virginia
"ChIJ-bDD5__lhVQRuvNfbGh4QpQ": 7738692, // Washington
"ChIJRQnL1KVUSogRQzrN3mjHALs": 1782959, // West Virginia
"ChIJr-OEkw_0qFIR1kmG-LjV1fI": 5895908, // Wisconsin
"ChIJaS7hSDTiXocRLzh90nkisCY": 578803, // Wyoming
};
}
initMap();
CSS
/*
* Always set the map height explicitly to define the size of the div element
* that contains the map.
*/
#map {
height: 100%;
}
/*
* Optional: Makes the sample page fill the window.
*/
html,
body {
height: 100%;
margin: 0;
padding: 0;
}
HTML
<html>
<head>
<title>Choropleth Map</title>
<link rel="stylesheet" type="text/css" href="./style.css" />
<script type="module" src="./index.js"></script>
</head>
<body>
<div id="map"></div>
<!-- prettier-ignore -->
<script>(g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})
({key: "AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg", v: "weekly"});</script>
</body>
</html>