NoData(Index: Integer): IGxImage;
Index. Scale tick mark index.
The NoData property determines the icon for the missing values.
Executing the example requires a form with the following components: the Button component named Button1, the MapBox component named MapBox1, and the UiMap component named UiMap1. UiMap1 is a data source for MapBox1. A map should be connected to the UiMap1 component. The VisualDataAdapter class that creates a dynamic data source should also be implemented. The class example is contained in the IMapVisual.DataAdapter property description. The file system should contain the files: C:\Greater.gif, C:\Exact.gif and C:\Less.gif with images.
The example is a handler of the OnClick event for the Button1 component.
Add links to the Drawing, ExtCtrls, Forms, and Map system assemblies.
Sub Button1OnClick(Sender: Object; Args: IMouseEventArgs);
Var
Map: IMap;
Layer: IMapLayer;
ImageVisual: IMapImageVisual;
ImageProp: IMapVisualIconProperty;
Scale: IMapIconScale;
Begin
Map := UiMap1.Map;
Layer := Map.Layers.FindByName("Regions");
ImageVisual := Layer.Visuals.AddImageVisual;
ImageVisual.DataAdapter := New VisualDataAdapter.Create As IMapDynamicDataAdapter;
ImageProp := ImageVisual.Image;
ImageProp.DataAdapter := ImageVisual.DataAdapter;
ImageVisual.Height.Value := 2;
ImageVisual.Width.Value := 2;
ImageProp.Dependent := True;
Scale := ImageProp.Scale;
Scale.Count := 1;
Scale.Value(0) := 50;
Scale.Greater(0) := GxImage.FromFile("C:\Greater.gif");
Scale.Less(0) := GxImage.FromFile("C:\Less.gif");
Scale.NoData := GxImage.FromFile("C:\Exact.gif");
End Sub Button1OnClick;
After executing the example the icon indicator is added to the Regions layer. The indicator icon is determined by the scale:
The values greater than fifty are indicated with the 
icon; the values less than fifty - with the 
icon; the missing values - with the 
icon.
See also: