Creating a (small) GUI

For example creating a GUI by changing some parameters:

scf(4);
addmenu(4,'Load',['New Sample'],list(0,'Load'));
Load_4=['disp(''act1=444;'')'];

that works well: and now I like to create something like this:

addmenu(4,'Load',['New Sample'],list(2,'Load'));
Load_4=[uigetfile(["*.*"])];
//Load_4=['uigetfile(["*.*"])'];=error
//4-number of window
//2-scilab subroutine

That means, by click on the button 'New Sample' the subroutine should open the getfile-dialog - but it does not.

The disp-operation is useless, because act1=444 is only an string and not further usable like: if act1=444 ...

Any thing that can help me?

Thank you!