How to Change a Value of parameter in GUI and automatically change in script file.

i think the answer is easy but i'm new in MATLAB world.. i have two buttons if the user press any of them the Value of I1 will change.

this is my function:

function PU = testfun
I1=0;
B1=uicontrol('Style',...
            'pushbutton',...
            'String',' 1 ',...
            'Position',[10 350 100 30],...
            'HandleVisibility','on',...
            'Callback',@PushB1);
B2=uicontrol('Style','pushbutton',...
            'String',' 2 ',...
            'Position',[10 150 100 30],...
            'HandleVisibility','on',...
            'Callback',@PushB2);
function PushB1(~,~)

    I1=1;
end
function PushB2(~,~)

    I1=2;

end 
end

And here is the script :

GS=20;
PU = testfun
if I1 ==1 
   GS=GS-5;
end

if I1 ==2 
   GS=GS-10;
end

I DID TRY GLOBAL BUT IT DID NOT WORK. thank you.

Answer 1

[Jan]

function PU = testfun
H = figure;
uicontrol('Style',...
          'pushbutton',...
          'String',' 1 ',...
          'Position',[10 350 100 30],...
          'HandleVisibility','on',...
          'Callback', {@PushB, 1});
uicontrol('Style','pushbutton',...
          'String',' 2 ',...
          'Position',[10 150 100 30],...
          'HandleVisibility','on',...
          'Callback', {@PushB, 2});
set(H, 'UserData', 0);
uiwait(H);  % Let Matlab wait until UIRESUME is called
PU = get(H, 'UserData');
end

function PushB(ButtonH, ~, Num)  % Same callback for both buttons
H = ancestor(ButtonH, 'figure');
set(H, 'UserData', Num);
uiresume(H);
end

[Oddineus]

thank you a lot .. it work with me fine.