You can create custom labels for a map legend using an expression that references several columns of text in a map layer table. For a description of how to do this, see Using an Expression to Customize Legend Label Text.
The attributes for each legend frame, such as the title and label styles, can be derived from the additional sources. These are:
- Joined tables Select to join tables "on-the-fly", to obtain legend feature descriptions from another table while you are creating a legend, see Creating a Legend with Joined Information.
- Map table metadata Save default settings that are unique to a map layer as metadata in its table, see Saving Legend Attributes to Metadata.