A theme is a set of geographic features in a
This data can be on a local disk or accessed across a network. A theme points
to the geographic data it represents. It does not contain the data itself.
The themes in a view are listed in its Table of Contents. For example, a view
of a country might have one theme representing cities, one theme representing
roads, one representing an satellite image, etc.
Normally, a theme represents all the features in a particular feature class,
but you can also define a feature selection property for a theme so that it only
represents a specific subset of these features. For example, if you have a
data source containing roads you can define a theme that represents just the major
roads.
Themes have a number of other properties that you can set to control their
characteristics. For example, you can specify the range of scales at which the
theme will be drawn on the view.
Each theme has its own legend displayed in the Table of Contents. A theme's
legend controls how the theme is displayed on the view. To change the colors and
symbols used to display a theme, you edit the theme's legend.
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See also
What is a theme?
A spatial data source such as an "ARC/INFO coverage" or "ArcView shapefile".
Most ARC/INFO coverages contain several different classes of features, such as
polygons and label points, in which case only one of these classes is
represented in the theme. An ArcView shapefile can represent point, line or polygon
features. You can edit the features of a theme that is based on the ArcView
shapefile format.
An image data source such as a satellite photo.
A tabular data source containing events such as a table with XY coordinates,
or a file of customers that ArcView can geocode.