WMS imageryLayers removal / refresh

CesiumJS
1

I'm having a some trouble understanding how to remove this layer on a timer the basic idea is to refresh the wms layer so from what I have looked at the best way is to remove it and add it again maybe using a extra parameters like date : Math.random(); but I'm stumped on removing the layer is it something like viewer.remove(radar, true); I guess I could use a code sample to understand it more. It would be great to get a sample so I could understand it.

var radar = viewer.imageryLayers;
imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
    url : '//mesonet.agron.iastate.edu/cgi-bin/wms/nexrad/n0r.cgi?',
    layers : 'nexrad-n0r',
    parameters : {
        transparent : true,
        format : 'image/png'
    }
}));

2

Hello,

You can use viewer.imageryLayers.remove function. Here is an example:

//Add the layer
var imageryLayers = viewer.imageryLayers;
var layer = imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
url : ‘//mesonet.agron.iastate.edu/cgi-bin/wms/nexrad/n0r.cgi?’,
layers : ‘nexrad-n0r’,
parameters : {
transparent : true,
format : ‘image/png’
}
}));

//Remove the layer
imageryLayers.remove(layer);

``

Best,

Hannah

3

Got it, one more problem is come up layer.alpha = 0.5;
is not working after I readd the layer? Am I doing something incorrectly or is there a way to default the layer alpha to .5?
function myTimer() {
imageryLayers.remove(layer);
imageryLayers.remove(warnings);
var layer = imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
    url : '//mesonet.agron.iastate.edu/cgi-bin/wms/nexrad/n0r.cgi?',
    layers : 'nexrad-n0r',
    parameters : {
        transparent : true,
        format : 'image/png',
        mydata : Math.random()
    }
}));
var warnings = imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
    url : '//mesonet.agron.iastate.edu/cgi-bin/wms/us/wwa.cgi?',
    layers : 'warnings_p',
    parameters : {
        transparent : true,
        format : 'image/png',
        mydata : Math.random()
    }
}));
layer.alpha = 0.5;
}

4

Uncaught TypeError: Cannot read property ‘remove’ of undefined

wx1.html:100 Uncaught TypeError: Cannot read property ‘remove’ of undefinedmyTimer @ wx1.html:100

also getting this error?

5

You have to be careful about the scope of your variables in Javascript. Moving var layer and var warnings outside of the function should solve the problem:

var layer;
var warnings;
function myTimer() {
imageryLayers.remove(layer);
imageryLayers.remove(warnings);
layer = imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
url : '//mesonet.agron.iastate.edu/cgi-bin/wms/nexrad/n0r.cgi?’,
layers : ‘nexrad-n0r’,
parameters : {
transparent : true,
format : ‘image/png’,
mydata : Math.random()
}
}));
warnings = imageryLayers.addImageryProvider(new Cesium.WebMapServiceImageryProvider({
url : '//mesonet.agron.iastate.edu/cgi-bin/wms/us/wwa.cgi?’,
layers : ‘warnings_p’,
parameters : {
transparent : true,
format : ‘image/png’,
mydata : Math.random()
}
}));
layer.alpha = 0.5;
}

``

-Hannah

6

Make sure var imageryLayers = viewer.imagerLayers; is included in your code.

-Hannah