topic Re: UniqueValueRenderer change polygon fill color dynamically in ArcGIS API for Silverlight Questions

UniqueValueRenderer change polygon fill color dynamically

xariaD — Fri, 16 Jul 2010 03:16:00 GMT

How to change the fill color of a particular polygon at runtime?

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Fri, 16 Jul 2010 13:55:57 GMT

This thread http://forums.arcgis.com/threads/6481-Dynamically-change-color-of-a-symbol?highlight=symbol+binding could help (by replacing markersymbol by fillsymbol).

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Mon, 19 Jul 2010 00:37:40 GMT

My problem lies in retrieving the polygon from feature layer.
The feature layer has multiple polygons. Also, I have a table stored in SQL database which stores status values of these polygons.
When the status changes the color should change.
So suppose if for polygon 1 status is 1 color is green,
then when the status for polygon changes to 0 the color should be red.

How do I apply the color change to polygon 1wiithout changing the color of other polygons?

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Mon, 19 Jul 2010 08:22:09 GMT

Looks like a standard usage of an UniqueValueRenderer.

Create two symbols (in your resources), one green and one red.
In your UniqueValueRenderer, affect the red symbol to value 0 and the green one to value 1.

The symbol will automatically change when the status value changes.

See sample http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#RenderersXAML

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Mon, 19 Jul 2010 09:02:20 GMT

So does that mean Status should be defined as an attribute of the feature?

But the status changes dynamically, and the status is passed to the WPF application via WCF operation.
So how to assign the new attribute value?

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Sat, 11 Dec 2021 10:54:14 GMT

So does that mean Status should be defined as an attribute of the feature?

Yes, it's the easiest way.

But the status changes dynamically, and the status is passed to the WPF application via WCF operation.
So how to assign the new attribute value?

You can add attributes at runtime :

 
if (graphic.Attributes.ContainsKey("Status"))
  graphic.Attributes["Status"] = status;
else
  graphic.Attributes.Add("Status", status);

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Sat, 11 Dec 2021 10:54:17 GMT

Yes, it's the easiest way.

You can add attributes at runtime :

 
if (graphic.Attributes.ContainsKey("Status"))
  graphic.Attributes["Status"] = status;
else
  graphic.Attributes.Add("Status", status);

When should the attribute be added? During layer Initialization? Or do I need to add a task?

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Tue, 20 Jul 2010 06:32:00 GMT

The attributes are not displayed in the WPF application.
I have attributes like ObjectId, RefName, text, txtMemo, status
but the feature layer has attribute
RefName, Shape_Length and Shape_area
😞

Ans as usual the web application is showing the attributes under the identify feature correctly!!!!!
:mad:

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Tue, 20 Jul 2010 15:56:25 GMT

I have added attributes to the map in ArcMap, and the REST service also displays all the attributes as fields. The web application displays all attributes in the identify table.

But WPF Application does not display those attributes. WHAT could be the reason? What should I check please guide me.

Re: UniqueValueRenderer change polygon fill color dynamically

dotMorten_esri — Tue, 20 Jul 2010 16:49:59 GMT

Did you set the OutFields property on the FeatureLayer?

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Wed, 21 Jul 2010 00:56:41 GMT

Did you set the OutFields property on the FeatureLayer?

Yeah I missed that.

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Wed, 21 Jul 2010 01:34:39 GMT

But I still don't understand how to dynamically apply the renderer.
The status of all graphic when the map is loaded is 0.
The status changes after the application starts.
So when I set the graphic.Attributes["status"] to newstatus value, it is not rendered.
How to refresh renderer or apply new renderer?

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Wed, 21 Jul 2010 07:09:07 GMT

It should be automatic when you change the value of an attribute which is used in the renderer.

How looks your renderer which is using the attribute 'status'?

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Sat, 11 Dec 2021 10:54:20 GMT

 <esriSymbols:SimpleFillSymbol x:Key="MyYellowFillSymbol" Fill="YellowGreen" BorderBrush="Transparent" BorderThickness="2" />
            <esriSymbols:SimpleFillSymbol x:Key="MyRedFillSymbol" Fill="Red" BorderBrush="Transparent" BorderThickness="2" />
            <esri:UniqueValueRenderer x:Key="MyUniqueValueRenderer" Attribute="Status" >
                <esri:UniqueValueRenderer.Infos>
                    <esri:UniqueValueInfo Value="Off" Symbol="{StaticResource MyRedFillSymbol}" />
                    <esri:UniqueValueInfo Value="On" Symbol="{StaticResource MyYellowFillSymbol}"/>                    
                </esri:UniqueValueRenderer.Infos>
            </esri:UniqueValueRenderer>

And the feature layer is

<esri:FeatureLayer ID="towers" Url="http://MyMapURL/MapServer/0"
       Where="1=1" Renderer="{StaticResource MyUniqueValueRenderer}"
        MouseLeftButtonDown="FeatureLayer_MouseLeftButtonDown">
 <esri:FeatureLayer.OutFields>
         <sys:String>RefName</sys:String>
         <sys:String>Status</sys:String>
         <sys:String>Text</sys:String>
 </esri:FeatureLayer.OutFields>
</esri:FeatureLayer>

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Wed, 21 Jul 2010 11:27:00 GMT

So when I set the graphic.Attributes["status"] to newstatus value, it is not rendered.

<esri:UniqueValueRenderer x:Key="MyUniqueValueRenderer" Attribute="Status" >

Looks like you are using status in code and Status in XAML.
Attribute names are case sensitive.

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Wed, 21 Jul 2010 12:29:38 GMT

NOoooooooooooooooooooooooooo

I know it is case-sensitive, and I am using "Status" in code behind.

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Wed, 21 Jul 2010 14:23:23 GMT

Might be that the status is initialized with coded values such as 0 and 1 and your renderer is using strings "On"/"Off".

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Wed, 21 Jul 2010 14:55:00 GMT

No, that is not the case either.
The status is defined as String "On"/"Off" and I am assigning the same in code behind.
😞

Re: UniqueValueRenderer change polygon fill color dynamically

xariaD — Sat, 11 Dec 2021 10:54:23 GMT

 private void FeatureLayer_MouseLeftButtonDown(object sender, GraphicMouseButtonEventArgs e)
        {
            Graphic feature = e.Graphic;          
            feature.Attributes["Status"] = "On";
        }

This is what I have in code behind.
What to do??

Re: UniqueValueRenderer change polygon fill color dynamically

DominiqueBroux — Thu, 22 Jul 2010 09:09:08 GMT

I tested with your code and I didn't get any problem.
So I don't understand:confused:

I guess you have verified that your event handler 'FeatureLayer_MouseLeftButtonDown' is executed?

Which ArcGIS SL API version are you using?