I should admit the map property is not sufficient for the described use-case.
To modify the incoming data, the most feasible solution is to use data scheme. The full list of scheme methods you can find in the related docs chapter.
Also, please be aware that height: "100% is an invalid declaration for component sizing. The sizing properties ( height, width, gravity, etc. ) accept only numeric values, and the default behaviour ( no strict sizes ) assumes that the view will take all available space.
The only scenario where height and width can be set to a string value “auto” is the type of a data component ( such settings will be applied to all data items in a component ).