TcxGridChartCategories Class

Categories in a Chart View.

Declaration

TcxGridChartCategories = class(
    TcxCustomGridOptions,
    IcxGridChartItem
)

Remarks

A category is used to classify data for comparison. Data groups are used to create a hierarchy of data levels which determine the categories into which series values are grouped/aggregated, and provide the drill-down functionality in Chart Views.

The default categories provide a simple classification of series values without aggregation. In terms of databases, the default category stands for a data column which uniquely identifies and refers to the values (series values) within a data record.

Categories in unbound Chart Views are represented by an instance of the TcxGridChartCategories class (the TcxGridDBChartCategories class in data-aware Chart Views). Like any chart item (a series or data group), this class provides an identifier which is used to address categories as a View item by the ID (accessible via the ID property). Use the VisibleValues property to access the collection of values which correspond to the categories (called category values) that are displayed in the chart. To access the category values which correspond to the default categories, use the Values property.

The default categories retrieve data from a data store with the help of the DataBinding object which provides properties that are used to define the data type of the category values, associate an arbitrary value (via the DataBinding.Data property) with the default categories and perform any additional operations required.

To modify properties of the default categories at design time, you need to select the rightmost data level in a chart toolbox (provided that the View’s ToolBox.DataLevelsInfoVisible option is enabled) and switch to the Object Inspector.