How to see attribute values when binding to Feature Layer

Question

I have implemented the "Configurable Silverlight Template Viewer for ArcGIS 2.1"
(here's the link http://www.arcgis.com/home/item.html?id=67f62c5c30cc4b3ca942068e404c442c ) and I need to change the background color of a bound Label in the map tip ( I changed the TextBlock to a label). I understand the IValueConverter pretty well but I'm not sure how to read an attribute value from the binding in order to determine the color to use.

DominiqueBroux · Answer

You can set a background binding by code.
 
After your code:TextBlock valueBlock = new TextBlock() { TextWrapping = TextWrapping.NoWrap };

Binding valueBinding = new Binding() { Path = new PropertyPath(string.Format("[{0}]", field)), StringFormat= aliases[field] + ": {0}" };

valueBlock.SetBinding(TextBlock.TextProperty, valueBinding);

you can add code like: 
Binding colorBinding = new Binding{
    Path = new PropertyPath(string.Format("[{0}]", field)),
    Converter = new MyColorConverter()
};
valueBlock.SetBinding(TextBlock.ForegroundProperty, colorBinding );

Your converter will get the value of the field as input value (due to binding to [<field>]).

Note : in Silverlight the TextBlock has no BackGround property, so to set the background you will need to surround the textblock with a container or use the 'Label' control.

JohnLove · Answer

Thank you for your reply Dominique, The problem I'm having is due to TextBlocks being dynamically being generated with each one being assigned a different value by binding to the PropertyPath. I cannot figure out how to test each textblock as it is created in order to set it's color based on the attribute value (i.e. if the value <= 50 the color = green else the color = red). I have written a ValueConverter that returns a brush based on the value passed into it. I just don't know how to get the value to pass into it. Please see code below: private PopupWindow CreateTipWindow(FeatureLayerInfo lyrInfo, List outFields) { Dictionary aliases = new Dictionary(); foreach (Field f in lyrInfo.Fields) { if (f.Name != lyrInfo.DisplayField) aliases.Add(f.Name, f.Alias); } PopupWindow tipWindow = new PopupWindow() { ShowArrow = false, ShowCloseButton = false, }; tipWindow.Content = CreateFeatureTipContent(outFields, aliases); tipWindow.Background = this.myTaskbarWidget.Background; Binding titleBinding = new Binding() { Path = new PropertyPath(string.Format("[{0}]", lyrInfo.DisplayField)) }; tipWindow.SetBinding(PopupWindow.TitleProperty, titleBinding); if (lyrInfo.Name == "Building") tipWindow.TitleFormat = "Installation ID" + ": {0}"; else tipWindow.TitleFormat = lyrInfo.Name + ": {0}"; return tipWindow; } private FrameworkElement CreateFeatureTipContent(List fields, Dictionary aliases) { StackPanel stackBox = new StackPanel() { Margin = new Thickness(4, 1, 4, 1), Orientation = Orientation.Vertical }; foreach (string field in fields) { if (aliases.Keys.Contains(field)) { TextBlock valueBlock = new TextBlock() { TextWrapping = TextWrapping.NoWrap }; Binding valueBinding = new Binding() { Path = new PropertyPath(string.Format("[{0}]", field)), StringFormat= aliases[field] + ": {0}" }; valueBlock.SetBinding(TextBlock.TextProperty, valueBinding); stackBox.Children.Add(valueBlock); } } return stackBox; } private void MapControl_MouseClick(object sender, Map.MouseEventArgs mouseEventArgs) {

DominiqueBroux · Answer

The datacontext of the MapTip is set to the 'Attributes' of the current graphic, Attributes being a Dictionary. So a binding such as is working by supposing you have an attribute called 'Label' that you want to display. If you have an attribute storing a Brush (let's call it BackgroundBrush), you can directly set the background color by: If your attribute is just a color or a string representing a color, you need to write a value converter to convert the color to a brush: