Cannot get featureLayer to display under DynamicMapServiceLayer

GarethMann

I am trying to add 2 layers to my map, 1 featureLayer and 1 dynamicMapServiceLayer. The featureLayer needs to show up underneath the dynamicMapServiceLayer.

For some reason if I try to add the featurelayer first I get a "type error" in serverapi.arcgisonline.com:14:

TypeError
arguments: Array[2]
get message: function getter() { [native code] }
get stack: function getter() { [native code] }
set message: function setter() { [native code] }
set stack: function setter() { [native code] }
type: "non_object_property_load"
__proto__: Error

If I add the featureLayer in after adding the dynamicMapServiceLayer it works fine and I get no error. However I need the featureLayer to be under the dynamicMapServiceLayer not ontop. I have tried to add it to the map with an index of 0 (map.addLayer(featureLayer,0)) but it still puts it on top. I have tried to use "map.reorderLayer" but it does not seem to do anything, it still shows up on top. What am I doing wrong and why will the featureLayer not show up under the dynamicMapServiceLayer?

Here is my page:

http://northmiamicra.org/PWorksLayout.html

StephenLead

If I add the featureLayer in after adding the dynamicMapServiceLayer it works fine and I get no error. if I try to add the featurelayer first I get a "type error"

I think the map is taking on the properties (such as extent and coordinate system) of the Dynamic layer, which then allows you to add the Feature Layer. See the Dynamic Map help entry which says: "If the first layer added to the map is an ArcGISDynamicMapServiceLayer, the map will take on the projection of this layer."

You could try specifying these properties when you declare the Map object:

//specify the initial extent and coordinate system
 var initExtent = new esri.geometry.Extent({"xmin":-9270392,"ymin":5247043,"xmax":-9269914,"ymax":5247401,"spatialReference":{"wkid":102100}});
//create map
map = new esri.Map("mapDiv",{extent:initExtent}); 

This should allow you to add the Feature layer to the map without first requiring the Dynamic layer.

What am I doing wrong and why will the featureLayer not show up under the dynamicMapServiceLayer?

A Feature layer is a type of Graphics layer, and according the help file, "Graphics layers can be reordered within the group of graphics layers. However, the graphics layer in Map.Graphics is always on top. Also, all graphics layers are always on top of TiledMapServiceLayers and DynamicMapServiceLayers."

So you may need to change the way you're adding these layers, and either use two Feature layers, or two Dynamic layers.

Steve