skip to main content
Gantt > Programmer's documentation > Developing with the JViews Charts SDK > Handling chart renderers > Chart renderers
 
Chart renderers
The way data is rendered on the screen (polyline, bar, area, and so on) is handled by dedicated objects called renderers.
Renderers are divided into three categories:
*Single renderers, which display data from one (or several) specific data set(s).
*Composite renderers, which display data from a specific data source, using one or more single renderers.
*Simple renderers, which display data from a specific data source.
The composite renderers are defined as a combination of other renderers, which can be either single renderers or other composite renderers, so that each data set in the associated data source is rendered by one of these child renderers.
The simple renderers do the rendering of an entire data source by themselves, without dispatching the drawings of different data sets to different renderers.
Chart renderers are instances of IlvChartRenderer subclasses. The composite renderer classes inherit from the IlvCompositeChartRenderer abstract class, and the single renderer classes inherit from the IlvSingleChartRenderer abstract class. The simple renderer classes inherit from the IlvSimpleChartRenderer abstract class.
In addition to these three main categories, we can distinguish a special type of composite renderers that handles a one-to-one relation between its child renderers and its data sets (that is, one child renderer per data set). These composite renderers are instances of the IlvSimpleCompositeChartRenderer class, and handle IlvSingleChartRenderer instances as child renderers.
Most of the composite chart renderer classes available in the JViews Charts library are subclasses of IlvSimpleCompositeChartRenderer.
Chart Renderer Hierarchy shows the chart renderer hierarchy:
Chart Renderer Hierarchy
A data model is drawn in a chart when it is bound to a renderer added to a chart. Depending on the data model, this association is performed between:
*A data source and a composite chart renderer if the data model is a data source.
Set the data source as the current renderer data source by means of the setDataSource method.
*A data set and a single chart renderer if the data model is a data set.
Add the data set to the renderer data source by means of the addDataSet method.

Copyright © 2018, Rogue Wave Software, Inc. All Rights Reserved.