That vertcat line should produce an error because ListString is not the name of a variable (rather, it's a parameter that you pass in the previous line). Regardless, you don't need to convert the cell array to anything because you already have the index of the selected file in indx.
Do you ever expect more than one option to be selected in the GUI? If not, I would recommend replacing the if statements with a switch statement, like this:
list = {'H','H2','H20'};
[indx,tf] = listdlg('ListString',list);
% Call different functions depending on user's selection
switch indx
case 1
S1_H;
case 2
S2_H2;
case 3
S3_H20;
end
If the user may select more than one option, then if statements would be more appropriate. If more than one option is selected, then more than one of the functions will need to be called. This means that each string must be checked for in a separate if statement (no elses).
list = {'H','H2','H20'};
[indx,tf] = listdlg('ListString',list);
% Check whether each string was selected in GUI, run functions accordingly.
% This setup allows user to select more than one string.
if sum(indx==1)>0
S1_H;
end
if sum(indx==2)>0
S2_H2;
end
if sum(indx==3)>0
S3_H20;
end
Hope this helps!
