Setting transparency on sublayers of an ArcGISDynamicMapServiceLayer?

[lhdasilva]

I am working on a Flex component to allow users to change a layer's transparency. This component gets what layer to use from another component that is a TOC. I want to be able to change the transparency of a sublayer in an ArcGISDynamicMapServiceLayer, but I see that the item type I get is LayerInfo (no alpha...).

Is this possible at all, or can I only change transparency on the entire map service layer (thus affecting all the sublayers)?

Any insight would be appreciated!

(Note: I am using Flex API 2.4).

Thanks,
-Luiza

[rockzZ25]

I think at the moment it only works with the map service itself and not the sublayers.

[ibespalov]

ihdasilva,

no, it is not possible. (The only way, if you initialize each sub layer as ArcGISDynamicMapServiceLayer )

Here is important to understand how is it works.

1 - ArcGISDynamicMapServiceLayer is container for IMAGE exported from server,
parameters you set for ArcGISDynamicMapServiceLayer are IMAGE export parameters.
Not 55 images for 55 sublayers, but 1 image exported form server for 55 sublayers.

2 - Flex Map is container for all layers:
static layer (navigation, scalebar, copyright, logo ...),
map layers (each 1 is something like flex display object / container ))
The transparency you set for ArcGISDynamicMapServiceLayer is alpha parameter for flex component (for IMAGE - 1 image for 55 sublayers)

Right?

Look at this discussion. May be you do not need to change transparency in flex code, but you set layers transparency in mxd file.

[dpaddock]

You can control the transparency of the sublayers if you're using ArcGIS 10.1 and the 3.0 API.

See:
http://resourcesbeta.arcgis.com/en/h...ons.html#alpha

[ykchin]

One opinion (if there really is not other way) is to romove the sublayer from the mapservicelayer in code and to bring in the same mapservicelayer again with only the sublayer.