ListBox.CellBold
From Xojo Documentation
Method
ListBox.CellBold(row as Integer, column as Integer) As Boolean
Supported for all project types and targets.
Supported for all project types and targets.
Used to add or remove the bold style from the text of the specified cell. Note that row and column are zero-based.
Example
Assign True to add the bold style and False to remove the bold style. For example:
ListBox1.CellBold(1, 1) = True