topic Re: SsnappingManager only snaps to map graphics in ArcGIS JavaScript Maps SDK Questions

SsnappingManager only snaps to map graphics

AdrianMarsden — Wed, 17 Apr 2013 13:13:21 GMT

Hi

I have a internal project about to go live, I really want to have snapping for measurements and user added graphics.

At the moment a simple

map.enableSnapping({ snapKey: dojo.keys.copyKey });

gets it on. However snapping only appears to work against already drawn graphics, not on any of my vector layers on my map. My map is made up of four ArcGISDynamicMapServiceLayer - added like this

    var background = new esri.layers.ArcGISDynamicMapServiceLayer(mapservice1, { "id": "mainbasemaps" });   // map.addLayer(background);       background.setDPI(150);     var altmaps = new esri.layers.ArcGISDynamicMapServiceLayer(altbasemaps, { "id": "altbasemaps" });    // map.addLayer(altmaps);     var aerials = new esri.layers.ArcGISDynamicMapServiceLayer(aerialservice, { "id": "aerialmaps" });       //map.addLayer(aerials);     dynamicMapServiceLayer = new esri.layers.ArcGISDynamicMapServiceLayer(mapservice2, { "id": "mainmap" });     dynamicMapServiceLayer.setOpacity(0.9);     dynamicMapServiceLayer.setDPI(96)     map.addLayers([background],[altmaps],[aerials],[dynamicMapServiceLayer]);

from the API documentation

Reference to a feature or graphics layer that will be a target snapping layer. The default option is to set all feature and graphics layers in the map to be target snapping layers.

So I would have thought it would snap to everything?

I've tried defining a specific layer like

var snappinglayer = new esri.layers.FeatureLayer(mapservice2 + "/4", {        mode: esri.layers.FeatureLayer.MODE_ONDEMAND,         outFields: ["*"]     }); ... var layerInfos = [{ layer: snappinglayer }];     snapManager.setLayerInfos(layerInfos);

But that fails.

Any ideas what I've missed?

ACM

Re: SsnappingManager only snaps to map graphics

JohnGravois — Wed, 17 Apr 2013 15:45:03 GMT

im not sure i understand. are you trying to snap to a featureLayer which hasn't been added to the map because youre already drawing it in a DynamicMapServiceLayer?

Re: SsnappingManager only snaps to map graphics

AdrianMarsden — Wed, 17 Apr 2013 16:29:36 GMT

Ah, do I understand correctly then, that the snapping only works on feature layers added to the map? I guess so

Reference to a feature or graphics layer that will be a target snapping layer. The default option is to set all feature and graphics layers in the map to be target snapping layers.

If so it would explain a lot as I have no feature layers, just dynamic ones.

So, if I add a feature layer to the map - does it have to be visible?

Cheers

ACM

Re: SsnappingManager only snaps to map graphics

JohnGravois — Wed, 17 Apr 2013 18:55:11 GMT

i haven't done any testing with this at all, but my guess would be that only the graphics being drawn would be "snap enabled".

Re: SsnappingManager only snaps to map graphics

JianHuang — Wed, 17 Apr 2013 19:50:50 GMT

Yes, the featureLayer has to be added to the map and it has to be visible.

Ah, do I understand correctly then, that the snapping only works on feature layers added to the map? I guess so

If so it would explain a lot as I have no feature layers, just dynamic ones.

So, if I add a feature layer to the map - does it have to be visible?

Cheers

ACM

Re: SsnappingManager only snaps to map graphics

AdrianMarsden — Thu, 18 Apr 2013 07:32:20 GMT

Cheers - I'm sure I tried that, but I'll have another go.

Thanks

ACM

Re: snappingManager only snaps to map graphics

AdrianMarsden — Thu, 18 Apr 2013 09:35:36 GMT

sorted - thanks - I must have read the API notes several times without noticing it said feature.

Cheers

ACM