How can I determine when an overlay in the LayerGroup has been switched on/off?

[Patrick Doody]

I have a set of overlay layers in an L.layers group. When they are toggled on/off, I need various things to happen. I have yet to find a way to determine if these overlays are on/off. There are no methods to check for visibility of the layer groups, or on the markers contained in each of these groups. Is there anything I can do to check if an overlay group in the layers control is on/off, short of navigating through the DOM to get the value of the checkbox?

Thanks,

Patrick

[Stephan Meijer]

Just from the top of my head, please check and validate!

 

var myLayer = L.tileLayer('http://{s}.tile.cloudmade.com/{key}/{styleId}/256/{z}/{x}/{y}.png', {

    key: 'API-key',

    styleId: 997

}).addTo(map);

map.on('layerremove', function(event) {

     if(event.layer == myLayer) {

         // do your events.

     }

});

map.on('layeradd', function(event) {

     if(event.layer == myLayer) {

         // do your events.

     }

});

map.addLayer(myLayer);

Op woensdag 23 januari 2013 16:11:29 UTC+1 schreef Patrick Doody het volgende:

[Stephan Meijer]

Oh, and checking if an layer is turned on in the Layer Control, is equal to checking if it exists on the map. 

map.hasLayer(myLayer);

Op woensdag 23 januari 2013 16:45:17 UTC+1 schreef Stephan Meijer het volgende:

[Patrick Doody]

Perfect! HasLayer() is exactly what I needed. I missed this! Thanks Stephan.

[Arnie Shore]

Great! I'd been looking for a layer-control event, and this meets my needs.

AS

On 1/23/13, Stephan Meijer <stephan...@gmail.com> wrote:
> Just from the top of my head, please check and validate!
>
>

> var myLayer = ...