legendId

LegendID is a term used in information technology to denote an identifier associated with an entry in a legend, typically in the context of maps, charts, or user interface components. It is not a formal standard, but a common naming convention used in data schemas and software libraries to link a visual legend item to the underlying data series, symbol, or category.

In GIS and cartography, legends describe symbols or patterns. Each symbol entry can have an ID that maps to a symbol, styling rule, or data subset, allowing applications to update or localize the legend without altering the view. The legendId can be used to programmatically reference a legend item for actions such as highlighting, filtering, or accessibility.

In data visualization libraries and dashboards, a legend item often carries a legendId property that connects the legend to a specific data series or category. This enables interactions such as clicking a legend item to toggle visibility, or synchronizing legend states with other components. Naming conventions vary by language and library, with legendId, legend_id, or LegendID all seen in practice. Typical values are strings or UUIDs, but numeric IDs are also possible. In practice, exact naming varies; some codebases use the form 'legendid' as a single-word field name or URL parameter, while others use camelCase like legendId or snake_case like legend_id.

Common considerations include ensuring global uniqueness within a document, respecting serialization formats, and documenting the mapping between legendId and the corresponding data or symbol. See also legend, data visualization, mapping, user interface.