2012

Table Of Contents
It is important to be aware of new layers that have been added to a drawing
or to an attached xref without your knowledge. You can avoid potential
problems, such as plotting objects that were added to the drawing by the
addition of a new layer.
You can control when to evaluate a drawing for new layers. You can specify
which commands, such as SAVE or PLOT, trigger the program to check the
layer list and alert you of new layers. This can include new layers that have
been added to attached xrefs.
The LAYEREVAL and LAYERNOTIFY system variables work together to control
whether the layer list is evaluated and when notification occurs. Both system
variables are saved in the drawing so you have control over which drawings
are checked for new layers. When a project is started, it may not be necessary
to know when new layers have been created. For drawings that are nearing
completion, it may be important to be aware if new information has been
introduced into the drawing from the addition of new layers.
The LAYEREVALCTL controls the overall Unreconciled New Layer filter list
in the Layer Properties Manager which is evaluated for new layers. When the
New Layer Notification is checked (LAYEREVALCTL = 1), the new layer
notification feature is enabled and functions based on the LAYEREVAL and
LAYERNOTIFY drawing system variables. There should be no filter
(Unreconciled Layer filter) displayed when LAYEREVALCTL = 0. If one is
currently displayed, it will be turned off.
By default, LAYEREVAL is set to detect any new layers that have been added
to attached xrefs but not in the drawing. LAYERNOTIFY is set to notify you
of new layers when opening the drawing, when loading, reloading, or attaching
xrefs, or when restoring a layer state. To make changes to these settings, you
can either use the system variables or the Layer Settings dialog box.
When layer notification is turned on, an Unreconciled New Layers icon displays
on the status bar.
At that time, you can choose to view the new layers by right-clicking the icon
and clicking the View Unreconciled New Layers link from the menu. When
you click the link, the Layer Properties Manager opens, and the Unreconciled
New Layers filter is automatically selected. All new layers that have been added
to the drawing or attached xrefs are displayed in the list view.
544 | Chapter 16 Control the Properties of Objects