Get dynpro width / height

Hey guys,

whats that crap with specifing the width / height of a dynpro in lines and columns?

I try to find a value for the "extension" parameter of cl_gui_docking_container constructor.

What I want to achieve is that this parameter is filled with the current dynpro width (or height if I dock the container on top). But all I have is the current number of columns from sy-scols (or lines from sy-srows). The extension parameter can use millimeters or pixels but not columns or lines.

Can anyone tell me how to convert columns (rows) to millimeters?

Thanks in advance for all answers!

Best regards,

Torben