AW: [OpenLayers-Users] Shapefile overlay on OSM or google

[Ian Dunlop]

Hello,

Finally got around to trying this. It works.  Setting maxExtent on the
layer allows it to display on the map. Thanks for the advice.

Cheers,

Ian

On 28 March 2012 07:34, Andreas Hocevar <ahocevar at opengeo.org> wrote:

>  Hi,
>
> you need to specify a maxExtent on the overlay layer.
>
> Andreas.
> On Mar 27, 2012 9:34 AM, "Arnd Wippermann" <arnd.wippermann at web.de> wrote:
>
>> **
>> Hi,
>>
>> set always mapOptions, if you use a projection other than EPSG:4326.
>> Perhaps that solves your problem.
>>  mapOptions = {
>>     projection: new OpenLayers.Projection("EPSG:900913"),
>>     //displayProjection: new OpenLayers.Projection("EPSG:4326"),
>>     units: "m",
>>     numZoomLevels: 18,
>>     maxResolution: 5,
>>     maxExtent: new OpenLayers.Bounds(-20037508.34, -20037508.34,
>> 20037508.34, 20037508.34)
>> };
>> map = new OpenLayers.Map('map', mapOptions);
>>
>>
>> some layers with cities
>>
>> var gphy = new OpenLayers.Layer.Google(
>>     "Google Physical",
>>     {type: google.maps.MapTypeId.TERRAIN}
>> );
>> map.addLayer(gphy);
>>
>> osmLayer = new OpenLayers.Layer.OSM( "Simple OSM Map");
>> map.addLayer(osmLayer);
>>
>> esriTopo = new OpenLayers.Layer.ArcGIS93Rest( "ESRI Topo",
>>             "
>> http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer/export?f=image
>> ",
>>             {layers: "show:0"},
>>             {isBaseLayer:false, visibility:false}
>>         );
>>
>> esriTopo.setVisibility(true);
>> map.addLayers(esriTopo);
>>  Arnd
>>
>>
>>  ------------------------------
>> *Von:* openlayers-users-bounces at lists.osgeo.org [mailto:
>> openlayers-users-bounces at lists.osgeo.org] *Im Auftrag von *Ian Dunlop
>> *Gesendet:* Dienstag, 27. März 2012 12:59
>> *An:* openlayers-users at lists.osgeo.org
>> *Betreff:* [OpenLayers-Users] Shapefile overlay on OSM or google
>>
>>  Hello,
>>
>>  I am trying to overlay a shapefile polygon on top of an Open Streetmap
>> or google layer.  However, it only shows up when zoomed out and disappears
>> when zoomed in to the map. Any ideas why this would be happening? The
>> shapefile is being served by gesoserver and overlays correctly at all zoom
>> levels on another WMS layer eg
>> OpenLayers.Layer.WMS( "OpenLayers WMS", "
>> http://vmap0.tiles.osgeo.org/wms/vmap0", {layers: 'basic'} );
>>
>>  I have only just started using openlayers so there may be something I
>> am missing. If this is not possible then are there any layers in the wild
>> which have city names on them (that's all I need really).  Sample code
>> below:
>>
>>                  var map = new OpenLayers.Map('map');
>>         var mapLayer = new OpenLayers.Layer.Google();
>>         //var mapLayer = new OpenLayers.Layer.WMS( "OpenLayers WMS",
>>         //    "http://vmap0.tiles.osgeo.org/wms/vmap0", {layers:
>> 'basic'} );
>>
>>  var roads = new OpenLayers.Layer.WFS(
>>                "Roads",
>>                "http://localhost:8080/geoserver/wfs",
>>                {typename: 'topp:tasmania_roads'},
>>                {
>>                    typename: 'tasmania_roads',
>>                    featureNS: 'http://www.openplans.org/topp',
>>                    extractAttributes: false
>>                }
>>            );
>>        map.addLayers([mapLayer, roads]);
>>
>>  Cheers,
>>
>>  Ian
>>
>>  --
>> Ian Dunlop
>> myGrid Team
>> School of Computer Science
>> University of Manchester
>>
>> _______________________________________________
>> Users mailing list
>> Users at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/openlayers-users
>>
>>


-- 
Ian Dunlop
myGrid Team
School of Computer Science
University of Manchester
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