GEOG 863:
Web Application Development for Geospatial Professionals

5.4 Layer Types


5.4 Layer Types

ArcGIS Server publishes data layers of several different types, depending on whether the underlying data source is vector or raster, the amount of data being served, the needs of the apps consuming them, etc.  In this part of the lesson, we’re going to walk through the most commonly used types, describing how they differ from one another, how they can be distinguished from layers of other types, under what circumstances they’re intended to be used, and how they are incorporated into an app.

In a moment, we'll take a detailed look at the most useful layer types one by one.  Before doing so, here are some important properties that are defined under the abstract Layer class that is the parent to all of the layer sub-classes:

  • opacity: set to a value from 0 to 1, with 0 making the layer completely transparent and 1 making it completely opaque (solid),
  • title: set to a string specifying how the layer is labeled in widgets like the Legend and LayerList,
  • visible: set to a Boolean controlling whether or not the layer is turned on/off.