topic Re: Dynamically Remove Layer in ArcGIS API for Silverlight Questions

Dynamically Remove Layer

MikeTischler — Fri, 14 May 2010 19:10:21 GMT

Hi,
I've followed the API Example for adding a layer dynamically....but how do I remove one dynamically? I see plenty of examples for toggling visibility, but how do I actually remove it from the map? I'm buidling a table of contents that dynamically updates when a new layer is added. However, I can't figure out how to remove a layer if it's no longer necessary.

thanks,
mike

Re: Dynamically Remove Layer

DominiqueBroux — Sat, 15 May 2010 09:50:17 GMT

Remove the layer from the layer collection associated to the map.
Something like:

myMap.Layers.Remove(myLayer);

Re: Dynamically Remove Layer

MikeTischler — Tue, 18 May 2010 15:29:18 GMT

which seems easy enough...

but, if you add in 3 layers dynamically (following the example), how do you link them back to a MyLayer object in XAML? How can you get a layer index? How can you query a layer name?

Is there a way to do the layer removal through XAML, or must it be a function in C#/VB?

To be a bit clearer (my original post was pretty vague, I'll admit). I'm attempting to add a list of objects to a silverlight front end much like the example at http://resources.esri.com/help/9.3/arcgisserver/apis/silverlight/samples/start.htm#LayerList. This would be done dynamically...you can put in a URL for a service and a new checkbox/slider would appear for that layer underneath the already existing ones. BUT, I would also like to add a "close" button to the individual stack panels that would 1) Remove the layer from the map entirely and 2) remove the slider/checkbox/button . I'm having a hard time figuring out how to reference a layer to remove it from the map, if it's added dynamically, and through a control that uses binding such as in the example.

thanks very much for the help!

Re: Dynamically Remove Layer

DominiqueBroux — Sat, 11 Dec 2021 07:54:32 GMT

In the example, the datacontext of each item is the layer itself (it's why we can display the name, change the opacity....).
So if you add a 'Delete' button, you have to write a code like:

private void ButtonDelete_Click(object sender, System.Windows.RoutedEventArgs e)
{
 FrameworkElement element = sender as FrameworkElement;
 this.MyMap.Layers.Remove(element.DataContext as Layer);
}

The layer will be removed from the map and the button/checkbox/slider will be removed automatically as well (thanks to the SL/WPF binding).

Concerning your question about the layer removal through XAML, I don't think you can do that out of the box.

Re: Dynamically Remove Layer

MikeTischler — Tue, 18 May 2010 17:02:21 GMT

Perfect - Exactly what I was looking for. Thanks so much!

Re: Dynamically Remove Layer

dotMorten_esri — Wed, 19 May 2010 18:53:42 GMT

or simply: myMap.Layers.RemoveAt(index)

Re: Dynamically Remove Layer

EzequiasRodrigues_da_Rocha — Thu, 08 Sep 2011 18:28:16 GMT

But how to get a Layer object if it is in a grouplayer?

Thanks in advance.

Re: Dynamically Remove Layer

JenniferNery — Sat, 11 Dec 2021 07:54:35 GMT

New to v2.3 and v3.0 is GroupLayer. I'm not sure if we are talking about the same layer type here. If yes, to remove a child layer of GroupLayer, you would do:

var groupLayer = MyMap.Layers["MyGroupLayer"] as GroupLayer;
groupLayer.ChildLayers.RemoveAt(index);

Re: Dynamically Remove Layer

EzequiasRodrigues_da_Rocha — Thu, 08 Sep 2011 23:49:56 GMT

I am using agslib2.3 and I didn't find out this class GroupLayer. Could you paste the namespace for me please Jennifer?

Re: Dynamically Remove Layer

JenniferNery — Tue, 13 Sep 2011 18:42:47 GMT

Are you using ArcGIS API for Silverlight? The current version is 2.2.

We are currently working on 2.3. But a 3.0 Beta 1 can be downloaded through ESRI Beta Community with ArcGIS Server 10.1 Beta 1. Both v2.3 and 3.0 versions include GroupLayer. beta.esri.com/community/