Disable layer checkbox if no geometry on that zoomlevel (source=wms)?

Question

I have a map application using GXP which displays different data coming from different WMS sources. Some geometry is only available on certain zoomlevels (available via MaxScaleDenominator on the GetCapabilities). It should be only possible to select an overlay layer when you are at that minimum zoom level, otherwise it should be disabled. Any idea on how to do this?

Answer 1

Try comparing the Map's current resolution (map.getResolution() or layer.getResolution()) to the layer's minimum resolution (wmsLayer.minResolution)

non tested sudo code:

if(map.getResolution() < wmsLayer.minResolution){
     //disable layer selection.
}else{
     //enable layer selection.
}

Update:

Please take a look at this wiki page.