[OpenLayers-Users] Re: Example of GeoJson fetch via HTTP?

[Scott Chapman]

Hmm. Coordinates are not normal Lat/Lon?? Here's what my server is
returning, which should put a point over the center of the US.
How to make this work?

    md = {
            "type": "FeatureCollection",
            "features": [
              {"geometry": {
                  "type": "GeometryCollection",
                  "geometries": [
                      {
                          "type":"Point",
                          "coordinates":[-98.4375,39.774769]
                      }
                  ]
              },
              "type": "Feature",
              "id": "OpenLayers.Feature.Vector_107",
              "properties": {}}
            ]
         }
    return md


On Tue, Feb 28, 2012 at 2:41 PM, Scott Chapman <scott at mischko.com> wrote:
> Here's how you do this:
>
>        var vector_layer = new OpenLayers.Layer.Vector();
>        map.addLayer(vector_layer);
>
>        OpenLayers.Request.GET({
>               url: "/kiosks_status_geoJSON/",
>               headers: {'Accept':'application/json'},
>               success: function (req)
>                        {
>                        var g = new OpenLayers.Format.GeoJSON();
>                        var feature_collection = g.read(req.responseText);
>                        vector_layer.destroyFeatures();
>                        vector_layer.addFeatures(feature_collection);
>                        }
>           });
>
> If anyone has any pointers, I'd be happy to hear them!
>
> Scott
>
>
> On Mon, Feb 27, 2012 at 7:36 PM, Scott Chapman <scott at mischko.com> wrote:
>> I've got a map and want to add a layer to it from a bunch of GeoJSON
>> formatted features that I can fetch from the server at
>> /kiosks_status_geoJSON/.  The server will return JSON format output.
>>
>> Can someone point me to an example of how to do this or lay it out for me?
>>
>> Some of my points of confusion include:
>>
>> 1) The docs (http://dev.openlayers.org/releases/OpenLayers-2.11/doc/apidocs/files/OpenLayers/Format/GeoJSON-js.html)
>> say that a GeoJSON Format.read() will deserialize a GeoJSON string,
>> but the example
>> (http://dev.openlayers.org/releases/OpenLayers-2.11/examples/geojson.html)
>> shows a GeoJSON.read() being passed an actual javascript object that's
>> already been deserialized.  Is it smart enough to deal with both
>> cases?
>>
>> 2) The overall flow of things.   I think I should make a Request.GET
>> to fetch the URL, an event handler to deal with the response having a
>> Format.geoJSON.read() the result and vector_layer.addFeatures on that.
>>  I'd love to see an example of this setup.
>>
>> Thanks!
>> Scott