如何在Google地图上显示存储在Firebase数据库中的多个标记坐标 [英] How To Display Multiple Markers Coordinates Stored In Firebase Database On Google Maps

查看：176 发布时间：2018/7/4 20:34:53 html5 firebase google-maps-api-3 firebase-database geofire

本文介绍了如何在Google地图上显示存储在Firebase数据库中的多个标记坐标的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在尝试获取保存在firebase实时数据库中的坐标，并使用google maps API将它们显示在地图上。这是我到目前为止的代码。现在它打开并使用html5地理定位API显示用户当前位置，并使用Geofire将lat和long坐标同步到firebase实时数据库。

我不知道如何检索这些点并在谷歌地图上同时显示不同用户的多个点位置。如果有人能帮助我，我会非常感激。

 < script src =https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js>< / script>< script src =https://www.gstatic.com /firebasejs/4.12.1/firebase.js\"></script><!DOCTYPE html>< html> < HEAD> <标题>地理位置< /标题> < meta name =viewportcontent =initial-scale = 1.0，user-scalable = no> < meta charset =utf-8> <风格> / *始终显式设置地图高度以定义包含地图的div *元素的大小。 * / #map {height：100％; / / *可选：使示例页面填满窗口。 * / html，身体{身高：100％;保证金：0;填充：0; }< / style> <！ - 将其置于HTML头部内;现在不要使用异步延迟 - >< script src =https://www.gstatic.com/firebasejs/4.12.1/firebase.js>< / script>< script src = https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js\"></script> <脚本> var config = {apiKey：AIzaSyCWZjRe2CK8Hu2VN35AgZOQ7lQZKcI-UWM，authDomain：carrier-35d7c.firebaseapp.com，databaseURL：https://carrier-35d7c.firebaseio.com，projectId：carrier-35d7c，storageBucket： carrier-35d7c.appspot.com，messagingSenderId：827792028763}; if（！firebase.apps.length）{firebase.initializeApp（config）; } //在firebase位置创建一个节点，将位置添加为子键var locationsRef = firebase.database（）。ref（locations）; //在用户Firebase位置创建新的GeoFire密钥var geoFire = new GeoFire（locationsRef.push（））; < /脚本> < /头> <身体GT; < div id =map>< / div> <脚本> //注意：此示例要求您在浏览器提示//时同意位置共享。如果您看到错误地理位置服务//失败。，则表示您可能未授权浏览器找到您。 var map，infoWindow; var lat，lng; function initMap（）{map = new google.maps.Map（document.getElementById（'map'），{center：{lat：-34.397，lng：150.644}，zoom：18}）; infoWindow = new google.maps.InfoWindow; //尝试HTML5地理位置。 if（navigator.geolocation）{navigator.geolocation.getCurrentPosition（function（position）{lat = position.coords.latitude; lng = position.coords.longitude; var pos = {lat：lat，lng：lng}; _setGeoFire（） ; infoWindow.setPosition（pos）; infoWindow.setContent（'Location found。'）; infoWindow.open（map）; map.setCenter（pos）;}，function（）{handleLocationError（true，infoWindow，map.getCenter（） ）;}）; } else {//浏览器不支持Geolocation handleLocationError（false，infoWindow，map.getCenter（））; function handleLocationError（browserHasGeolocation，infoWindow，pos）{infoWindow.setPosition（pos）; infoWindow.setContent（browserHasGeolocation？'错误：Geolocation服务失败。'：'错误：您的浏览器不支持地理定位。'）; infoWindow.open（地图）; } function _setGeoFire（）{geoFire.set（User，[lat，lng]）。then（（）=> {console.log（Location added）;}）。catch（function（error）{console .log（错误）;}）;}< / script> < script src =https://maps.googleapis.com/maps/api/js?key=AIzaSyD2nPlSt_nM7PSKD8So8anbUbBYICFWcCA&callback=initMap> < /脚本> < / body>< / html>

解决方案

相关问题：

来自我的（有多个locat离子和上面修改过的代码）：

代码段

  function initialize（）{var infowindow = new google。 maps.InfoWindow（）; var map = new google.maps.Map（document.getElementById（map_canvas），{center：new google.maps.LatLng（37.4419，-122.1419），zoom：13，mapTypeId：google.maps.MapTypeId.ROADMAP}） ; //初始化Firebase var config = {apiKey：AIzaSyC8HcClvIT_FlG8ZwCji4LG-qNx8D9VCrs，authDomain：geocodeziptest.firebaseapp.com，databaseURL：https://geocodeziptest.firebaseio.com，projectId：geocodeziptest，storageBucket：geocodeziptest .appspot.com，messagingSenderId：1096545848604}; firebase.initializeApp（配置）; //在firebase位置创建一个节点，将位置添加为子键var locationsRef = firebase.database（）。ref（locations）; var bounds = new google.maps.LatLngBounds（）; locationsRef.on（'child_added'，function（snapshot）{var data = snapshot.val（）; console.log（data）; var marker = new google.maps.Marker（{position：{lat：data.lat，lng ：data.lng}，map：map}）; bounds.extend（marker.getPosition（））; marker.addListener（'click'，（function（data）{return function（e）{infowindow.setContent（data.name +< br>+ this.getPosition（）。toUrlValue（6）+< br>+ data.message）; infowindow.open（map，this）;}}（data）））; map。 fitBounds（bounds）;}）;} google.maps.event.addDomListener（window，load，initialize）;

  html，body，＃map_canvas {height：100％;宽度：100％;保证金：0px; padding：0px}

 < script src =https： //maps.googleapis.com/maps/api/js\"></script><script src =https://www.gstatic.com/firebasejs/4.12.1/firebase.js>< ; / script>< script src =https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js>< / script>< div id =map_canvas> ;< / div>

I am trying to get the coordinates that are saved in the firebase real-time database and display them on a map using the google maps API. This is the code I have so far. Right now it opens and shows the users current location using the html5 geolocation API and it syncs the lat and long coordinates to the firebase real-time database using Geofire.

I don't know how to retrieve these points and have multiple points on the google map at the same time showing different users locations. If anyone could help me with this I would really appreciate it.

<script src="https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js"></script>
<script src="https://www.gstatic.com/firebasejs/4.12.1/firebase.js"></script>
<!DOCTYPE html>
<html>
  <head>
    <title>Geolocation</title>
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no">
    <meta charset="utf-8">
    <style>
      /* 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;
      }
    </style>
    <!-- Place this inside the HTML head; don't use async defer for now -->
<script src="https://www.gstatic.com/firebasejs/4.12.1/firebase.js"></script>
<script src="https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js"></script>

  <script>
        
        var config = {
    apiKey: "AIzaSyCWZjRe2CK8Hu2VN35AgZOQ7lQZKcI-UWM",
    authDomain: "carrier-35d7c.firebaseapp.com",
    databaseURL: "https://carrier-35d7c.firebaseio.com",
    projectId: "carrier-35d7c",
    storageBucket: "carrier-35d7c.appspot.com",
    messagingSenderId: "827792028763"
  };

        if (!firebase.apps.length) {
            firebase.initializeApp(config);
        }
        
        //Create a node at firebase location to add locations as child keys
        var locationsRef = firebase.database().ref("locations");
        
        // Create a new GeoFire key under users Firebase location
        var geoFire = new GeoFire(locationsRef.push());
      </script>


  </head>
  <body>
    <div id="map"></div>
    <script>
      // Note: This example requires that you consent to location sharing when
      // prompted by your browser. If you see the error "The Geolocation service
      // failed.", it means you probably did not give permission for the browser to
      // locate you.

      var map, infoWindow;
      var lat, lng;
      function initMap() {
        map = new google.maps.Map(document.getElementById('map'), {
          center: {lat: -34.397, lng: 150.644},
          zoom: 18
        });
        infoWindow = new google.maps.InfoWindow;

        // Try HTML5 geolocation.
        if (navigator.geolocation) {
          navigator.geolocation.getCurrentPosition(function(position) {
            lat = position.coords.latitude;
            lng = position.coords.longitude;

            var pos = {lat: lat, lng: lng };
                _setGeoFire();
          

            infoWindow.setPosition(pos);
            infoWindow.setContent('Location found.');
            infoWindow.open(map);
            map.setCenter(pos);
          }, function() {
            handleLocationError(true, infoWindow, map.getCenter());
          });
        } else {
          // Browser doesn't support Geolocation
          handleLocationError(false, infoWindow, map.getCenter());
        }
      }

      function handleLocationError(browserHasGeolocation, infoWindow, pos) {
        infoWindow.setPosition(pos);
        infoWindow.setContent(browserHasGeolocation ?
                              'Error: The Geolocation service failed.' :
                              'Error: Your browser doesn\'t support geolocation.');
        infoWindow.open(map);
      }

      function _setGeoFire(){
    geoFire.set("User", [lat, lng]).then(()=>{
            console.log("Location added");
        }).catch(function(error) {
            console.log(error);
        });


}
    </script>
    <script 
    src="https://maps.googleapis.com/maps/api/js?key=AIzaSyD2nPlSt_nM7PSKD8So8anbUbBYICFWcCA&callback=initMap">
    </script>
  </body>
</html>

解决方案

Related question:

How to retrieve data from Firebase using Javascript?

I only get one result from that database:

c20ej76jhb
45.546058,-122.813203

Using this code (uses on rather than once) with a reference to a database I created with multiple locations (and a different format of data):

var locationsRef = firebase.database().ref("locations");
locationsRef.on('child_added', function(snapshot) {
var data = snapshot.val();
var marker = new google.maps.Marker({
  position: {
    lat: data.lat,
    lng: data.lng
  },
  map: map
});
bounds.extend(marker.getPosition());
marker.addListener('click', (function(data) {
  return function(e) {
    infowindow.setContent(data.name + "<br>" + this.getPosition().toUrlValue(6) + "<br>" + data.message);
    infowindow.open(map, this);
  }
}(data)));
map.fitBounds(bounds);

});

proof of concept fiddle

from your database:

from mine (with multiple locations and the modified code above):

code snippet:

function initialize() {
  var infowindow = new google.maps.InfoWindow();
  var map = new google.maps.Map(
    document.getElementById("map_canvas"), {
      center: new google.maps.LatLng(37.4419, -122.1419),
      zoom: 13,
      mapTypeId: google.maps.MapTypeId.ROADMAP
    });
  // Initialize Firebase
  var config = {
    apiKey: "AIzaSyC8HcClvIT_FlG8ZwCji4LG-qNx8D9VCrs",
    authDomain: "geocodeziptest.firebaseapp.com",
    databaseURL: "https://geocodeziptest.firebaseio.com",
    projectId: "geocodeziptest",
    storageBucket: "geocodeziptest.appspot.com",
    messagingSenderId: "1096545848604"
  };
  firebase.initializeApp(config);
  //Create a node at firebase location to add locations as child keys
  var locationsRef = firebase.database().ref("locations");
  var bounds = new google.maps.LatLngBounds();
  locationsRef.on('child_added', function(snapshot) {
    var data = snapshot.val();
    console.log(data);
    var marker = new google.maps.Marker({
      position: {
        lat: data.lat,
        lng: data.lng
      },
      map: map
    });
    bounds.extend(marker.getPosition());
    marker.addListener('click', (function(data) {
      return function(e) {
        infowindow.setContent(data.name + "<br>" + this.getPosition().toUrlValue(6) + "<br>" + data.message);
        infowindow.open(map, this);
      }
    }(data)));
    map.fitBounds(bounds);
  });
}
google.maps.event.addDomListener(window, "load", initialize);

html,
body,
#map_canvas {
  height: 100%;
  width: 100%;
  margin: 0px;
  padding: 0px
}

<script src="https://maps.googleapis.com/maps/api/js"></script>
<script src="https://www.gstatic.com/firebasejs/4.12.1/firebase.js"></script>
<script src="https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js"></script>
<div id="map_canvas"></div>

这篇关于如何在Google地图上显示存储在Firebase数据库中的多个标记坐标的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！

查看全文

如何在Google地图上显示存储在Firebase数据库中的多个标记坐标 [英] How To Display Multiple Markers Coordinates Stored In Firebase Database On Google Maps

问题描述

相关文章

前端开发最新文章

热门教程

热门工具

登录关闭

如何在Google地图上显示存储在Firebase数据库中的多个标记坐标 [英] How To Display Multiple Markers Coordinates Stored In Firebase Database On Google Maps

问题描述

相关文章

前端开发最新文章

热门教程

热门工具

登录 关闭

登录关闭