[OpenLayers-Users] wms untiled 'busy loading' message or image

[Richard Duivenvoorde]

Hi List,

What is the preferred way to implement some kind of 'loading or busy 
message' for a slow wms server?

I've got a map with some (faster) tiled reference layers, and one (slow) 
untiled wms top layer. While the reference layer loads pretty fast, the 
(dynamic) top layer is sometimes loaded after a few seconds. I want to 
inform users that they have to be patient for a while :-)

If there is some kind of callback mechanisme possible which is called 
when the image is loaded? So I can show an image while loading, and 
remove it when this callback function is called.

TIA

Richard Duivenvoorde