chart-items

Arguments: chart-widget

Returns the value of the chart-items property of a chart-widget. The value may be set at creation time by passing the :chart-items initarg, or any time later by calling (setf chart-items).

This property contains a tree of values that are displayed in a chart-widget. This tree is normally built indirectly by successive calls to set-chart-value. Values are looked up here when the chart is being drawn, or when an application calls chart-value.

An application normally does not need to access this property directly, though it could build the tree of values itself and call (setf chart-items) to set all of the values at once. Here is an example of a chart-items value:

((:values #((:value 164) (:value 152 :low-value 148) (:value 103))
  :id (2005 dec 12))
 (:values #((:value 168) nil (:value 145 :icon-size 6))
  :id (2006 feb 3))
 ...)

The value is a list where each element of the list represents one chart item. An element for one chart item is a property list that can contain an :id entry for the chart item's ID and/or a :values item that contains a sequence of values. The value sequence may be either a list or a vector. Each element of the value sequence is a property list that holds the values for one chart object at this chart item. This property list can contain entries for any of the allowed types of values (see set-chart-value).

In the example above, the first chart item species a value of 164 for the first chart object, a value of 152 and a low-value of 148 for the second chart object, and so on. The second chart item specifies nil as a placeholder for the second chart object (which has no value at this chart item) so that it can specify a value for the third chart object.

To avoid building this tree of values at all, use a chart-value-returner function instead.

See chart-widget and also cg-chart-widget.htm.

Copyright (c) 1998-2019, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 9.0 page.
Created 2015.5.21.