ArcObjects Library Reference (Carto)  

IUniqueValueRenderer Interface

Provides access to members that control a renderer where symbols are assigned to features based on unique attribute values.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Description

IUniqueValueRenderer is a way to show the features of a layer based on the unique values of one or more attributes.

Members

Description
Method AddReferenceValue Adds a value to the renderer to be grouped with refValue, which has already been added to the renderer.
Method AddValue Adds a value and corresponding symbol to the list. For multivariate cases, the specified value is a delimitted list of individual values.
Read/write property ColorScheme Color scheme (user interface property only).
Read/write property DefaultLabel Label used for unspecified values.
Read/write property DefaultSymbol Symbol used to draw any unspecified values (may be NULL).
Read/write property Description Desription for the specified label.
Read/write property Field Field at the specified index that is used to categorize features.
Read/write property FieldCount Number of fields used by the renderer (0-3).
Read/write property FieldDelimiter Delimiter used to separate field values.
Write-only property FieldType Indicates if the field at the specified index is a string.
Read/write property Heading Heading that contains the specified value.
Read/write property Label Label for the specified value.
Read/write property LookupStyleset Style used for matching (user interface property only).
Read-only property ReferenceValue Reference value for the specified value.
Method RemoveAllValues Removes all values from the renderer.
Method RemoveValue Removes a value from the renderer.
Read/write property Symbol Symbol associated with the specified value.
Read/write property UseDefaultSymbol Indicates if DefaultSymbol is used for drawing unspecified values.
Read/write property Value Value at the specified index.
Read-only property ValueCount Number of unique values used to categorize the data.

CoClasses that implement IUniqueValueRenderer

CoClasses and Classes Description
UniqueValueRenderer A unique values renderer where symbols are assigned to features based on an unique attribute values.

Remarks

Use IUniqueValueRenderer to work with the properties of a UniqueValueRenderer.

This interface is used to manage the list of categories and symbols. Each unique Value in your data can define a unique category, represented with a single Symbol, and values can also be combined by grouping so that more than one value is symbolized with the same symbol. To work with grouping use AddReferenceValue and ReferenceValue. Also, Headings can be used to organize categories in the table of contents and legend, use Heading to assign a value to a particular heading.

Unique value renderering is typically based on a single attribute Field, however up to 3 fields can be used. When more than one field is used, the combinations of the unique values from each field are used to define the categories. So, for example if two fields are used which store the values A and B; and X, Y, and Z respectively, then the initial categories will be defined as A|X, A|Y, A|Z, B|X, B|Y, and B|Z.