topic Re: Display Annotations in feature Layer in ArcGIS API for Silverlight Questions

Display Annotations in feature Layer

xariaD — Mon, 26 Jul 2010 08:20:19 GMT

How to display the labels for features of feature layer?

Re: Display Annotations in feature Layer

DominiqueBroux — Mon, 26 Jul 2010 13:44:03 GMT

You might use a custom symbol with a text which binds to an attribute.
This should be easy for points.

More difficult for polylines or polygones because you will have to find the label placement within.

Re: Display Annotations in feature Layer (using symbol ControlTemplate)

BrooksShannon — Sat, 11 Dec 2021 16:11:13 GMT

Dominique,

I'm trying to label points in a feature layer using a custom symbol (a MarkerSymbol with a custom ControlTemplate), and I think you're suggestion, above, is along the lines of what I'm attempting to do.

My question relates specifically to data binding: what I'd really like to do is use a binding statement within the XAML of my ControlTemplate to bind to one of my graphics' attributes - such that the label for each feature reflects each feature individually.

Here's the XAML I'm using, from the Renderer down to the ControlTemplate:

<esri:SimpleRenderer x:Key="AddressPointRenderer_Display">
    <esri:SimpleRenderer.Symbol>
        <esriSymbols:MarkerSymbol>
            <esriSymbols:MarkerSymbol.ControlTemplate>
                <ControlTemplate>                                        
                    <StackPanel Orientation="Vertical">                                        
                        <Ellipse x:Name="Element" Width="5" Height="5" StrokeThickness="10" 
                                    Stroke="Blue">
                            <VisualStateManager.VisualStateGroups>
                                <VisualStateGroup x:Name="SelectionStates">
                                    <VisualState x:Name="Unselected" />
                                    <VisualState x:Name="Selected">
                                        <Storyboard>
                                            <ColorAnimation Storyboard.TargetName="Element" 
                                                Storyboard.TargetProperty="(Ellipse.Stroke).(SolidColorBrush.Color)"
                                                To="Cyan" Duration="00:00:0.25"/>
                                        </Storyboard>
                                    </VisualState>
                                </VisualStateGroup>
                            </VisualStateManager.VisualStateGroups>
                        </Ellipse>
                        <TextBlock Foreground="DarkGreen" FontWeight="ExtraBold" Margin="0,10,0,0" Text="{Binding [MY_ATTRIBUTE]}" />
                    </StackPanel>
                </ControlTemplate>
            </esriSymbols:MarkerSymbol.ControlTemplate>
        </esriSymbols:MarkerSymbol>
    </esri:SimpleRenderer.Symbol>
</esri:SimpleRenderer>

The intent is that TextBlock's Text value should be whatever the "MY_ATTRIBUTE" value is, for each individual feature being rendered.

Is it possible to do this, like I'm attempting to do it? The binding fails, so I assume the DataContext is either different than what I expect it to be, or it's nonexistent (aka, I just can't do it this way).

Thanks!
Brooks

Re: Display Annotations in feature Layer

BrooksShannon — Wed, 13 Oct 2010 15:08:41 GMT

Dominique,

I figured it out. My binding statement was Text="{Binding [DLVRY_ADD]}", but it should be Text="{Binding Attributes[DLVRY_ADD]}" instead.

Have a good one,
Brooks

Re: Display Annotations in feature Layer

LakshmananVenkatesan — Fri, 22 Oct 2010 08:01:09 GMT

Hi Brooks:

Can you share full code?. I want display label for dynamic service layer as well?. Please help

SR

Re: Display Annotations in feature Layer

MattMiley — Thu, 06 Oct 2011 17:01:56 GMT

I second this, it is ridiculous that its this hard to add a label.

Re: Display Annotations in feature Layer

BrooksShannon — Fri, 07 Oct 2011 12:36:35 GMT

Guys,

What I posted above (which, mind you, just labels points) is essentially the full code. Bear in mind that my renderer XAML code, as originally pasted, had a binding expression error that I described the resolution for, in the subsequent post.

The only magic, then, to using this is to make the renderer a resource of your layer's parent - in my case a Grid, so the renderer's XAML code is a part within the Grid's <Grid.Resources> collection.

Then, in your feature layer, add an attribute to its declaration:

Renderer="{StaticResource AddressPointRenderer_Display}"

Which tells the layer that it must use your custom renderer.

Now, I can't say what tricks you'll need to do to perform special labeling in dynamic map service layers other than setting up labeling in your map service definition (via MXD or MSD)... or if you can do anything but that. This technique is really only applicable to Feature Layers (and by extension, general GraphicsLayers) as they are rendered client-side, giving you control of how the labeling occurs.

Let me know if you have any other questions.

Thanks!
Brooks