Waitbar error during calculation

Hello,

if I press button "x"- that I want to close waitbar for example during for i=1:a during calculation, I got error, why?

The second argument must be a message string or a handle to an existing waitbar.

Error in ==> Simulator>pushbutton5_Callback at 2543
                  waitbar(step/steps,calculation,sprintf([calculation,' %d%%
                  ...'],round(step/steps*100)));

This is my code:

calculation = waitbar(0,'Calculation...','Name','Status of calculation');

   for i=1:a; 
   step = 1+step;
   waitbar(step/steps,calculation,sprintf([actual caltulation,' %d%%...'],round(step/steps*100)));                      
   end;

for i=1:b; 
 step = 1+step;
 waitbar(step/steps,calculation,sprintf([actual caltulation,' %d%%...'],round(step/steps*100)));                      
 end;

for i=1:c; 
 step = 1+step;
 waitbar(step/steps,calculation,sprintf([actual caltulation,' %d%%...'],round(step/steps*100)));                      
 end;

Answer 1

[Image Analyst]

It was not expecting you to close it after you set it up and tried to use it again. To avoid the error message, wrap the call to waitbar in a try catch

try
  waitbar(step/steps,calculation,sprintf([actual caltulation,' %d%%...'],round(step/steps*100)));  
catch
  % Don't do anything in the catch, just ignore the error.
end

[john]

Is there possible to disable button "x"?