Question

罗伯托的帮助后编辑：

Python新手。该应用程序在前端使用Maps Javascript API v3。后端是webapp2 / GAE。我假设我也没有正确地做json。传递JSON后标记未正确创建。

    q = Building.query()
    buildings = q.fetch()
    some_json = []
    for building in buildings:
        some_json.append(OrderedDict([('lat', float(building.lat)), ('lng', float(building.lng)), ('content', building.uuid)]))
    appended_json = json.dumps(some_json)

HTML：

<!DOCTYPE html>
<html>
  <head>
    <style type="text/css">
      html, body, #map-canvas { height: 100%; margin: 0; padding: 0;}
    </style>
                <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
    <script type="text/javascript"
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyDMfzvCXM-LUe43cZ0mB2iDxx4aNOySkrQ">
    </script>
    <script type="text/javascript">
function initialize() {
            var input_value = document.getElementById("lat").value;
            var converted_value = JSON.stringify(input_value);
            console.log(input_value);
            var json = JSON.parse(converted_value);
            console.log(json);
            var locations = json;

    var map = new google.maps.Map(document.getElementById('map-canvas'), {
      zoom: 10,
      center: new google.maps.LatLng(-33.92, 151.25),
      mapTypeId: google.maps.MapTypeId.ROADMAP
    });

    var infowindow = new google.maps.InfoWindow();

    var marker, i;

    for (i = 0; i < locations.length; i++) {
      marker = new google.maps.Marker({
        position: new google.maps.LatLng(locations[i][0], locations[i][1]),
        map: map
      });

      google.maps.event.addListener(marker, 'click', (function(marker, i) {
        return function() {
          infowindow.setContent(locations[i][2]);
          infowindow.open(map, marker);
        }
      })(marker, i));
    }
    }
   google.maps.event.addDomListener(window, 'load', initialize);
    </script>
  </head>
  <body>
<div id="map-canvas"></div>
    <input id="lat" hidden="hidden" value="{{ appended_json }}">

  </body>
</html>

如果输出正确并且没有引发任何错误，控制台将输出以下内容：

 [{"lat": 39.2831792, "lng": -80.56741099999999, "content": "782f7100c13511e49f92ab5e18d4b38e"}] viewbuildings:17 
[{"lat": 39.2831792, "lng": -80.56741099999999, "content": "782f7100c13511e49f92ab5e18d4b38e"}]

即使输出不正确，它仍然不会引发任何事情。

编辑：

确切的HTML浏览器看到如下

<!DOCTYPE html>
<html>
  <head>
    <style type="text/css">
      html, body, #map-canvas { height: 100%; margin: 0; padding: 0;}
    </style>
                <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
    <script type="text/javascript"
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyDMfzvCXM-LUe43cZ0mB2iDxx4aNOySkrQ">
    </script>
    <script type="text/javascript">
function initialize() {
            var input_value = document.getElementById("lat").value;
            var converted_value = JSON.stringify(input_value);
            console.log(input_value);
            var json = JSON.parse(converted_value);
            console.log(json);
            var locations = json;

    var map = new google.maps.Map(document.getElementById('map-canvas'), {
      zoom: 10,
      center: new google.maps.LatLng(-33.92, 151.25),
      mapTypeId: google.maps.MapTypeId.ROADMAP
    });

    var infowindow = new google.maps.InfoWindow();

    var marker, i;

    for (i = 0; i < locations.length; i++) {
      marker = new google.maps.Marker({
        position: new google.maps.LatLng(locations[i][0], locations[i][1]),
        map: map
      });

      google.maps.event.addListener(marker, 'click', (function(marker, i) {
        return function() {
          infowindow.setContent(locations[i][2]);
          infowindow.open(map, marker);
        }
      })(marker, i));
    }
    }
   google.maps.event.addDomListener(window, 'load', initialize);
    </script>
  </head>
  <body>
<div id="map-canvas"></div>
    <input id="lat" hidden="hidden" value="[{&quot;lat&quot;: 39.2831792, &quot;lng&quot;: -80.56741099999999, &quot;content&quot;: &quot;782f7100c13511e49f92ab5e18d4b38e&quot;}]">

  </body>
</html>

Answer 1

您的代码期望您的JSON看起来像这样：

[[39.2831792,-80.56741099999999,"782f7100c13511e49f92ab5e18d4b38e"]]

你的JSON看起来不像，看起来像：

[{"lat": 39.2831792,"lng": -80.56741099999999,"content": "782f7100c13511e49f92ab5e18d4b38e"}];

更改代码以处理您的JSON格式：

for (i = 0; i < locations.length; i++) {
    marker = new google.maps.Marker({
        position: new google.maps.LatLng(locations[i].lat, locations[i].lng),
        map: map
    });
    google.maps.event.addListener(marker, 'click', (function (marker, i) {
        return function () {
            infowindow.setContent(locations[i].content);
            infowindow.open(map, marker);
        }
    })(marker, i));
}

您还错误地使用了JSON.stringify和JSON.parse。您的input元素的内容是一个JSON字符串，您只需将其传递给JSON.parse以从中获取JSON对象：

工作代码段：

＆＃13;

function initialize() {
  var input_value = document.getElementById("lat").value;
  var json = JSON.parse(input_value);
  var locations = json;

  var map = new google.maps.Map(document.getElementById('map-canvas'), {
    zoom: 10,
    center: new google.maps.LatLng(-33.92, 151.25),
    mapTypeId: google.maps.MapTypeId.ROADMAP
  });

  var infowindow = new google.maps.InfoWindow();

  var marker, i;
  var bounds = new google.maps.LatLngBounds();
  for (i = 0; i < locations.length; i++) {
    marker = new google.maps.Marker({
      position: new google.maps.LatLng(locations[i].lat, locations[i].lng),
      map: map
    });
    bounds.extend(marker.getPosition());
    google.maps.event.addListener(marker, 'click', (function(marker, i) {
      return function() {
        infowindow.setContent(locations[i].content);
        infowindow.open(map, marker);
      }
    })(marker, i));
  }
  map.fitBounds(bounds);
}
google.maps.event.addDomListener(window, 'load', initialize);

＆＃13;

html,
body,
#map-canvas {
  height: 100%;
  margin: 0;
  padding: 0;
}

＆＃13;

<script src="https://maps.googleapis.com/maps/api/js?sensor=false&libraries=geometry,places&ext=.js"></script>
<div id="map-canvas"></div>
<input id="lat" hidden="hidden" value="[{&quot;lat&quot;: 39.2831792, &quot;lng&quot;: -80.56741099999999, &quot;content&quot;: &quot;782f7100c13511e49f92ab5e18d4b38e&quot;}]">

＆＃13;

传递JSON后未创建标记

1 个答案: