How can I have a dialog box or user prompt with a time-out period?

Can I get code that provides time-out functionality for dialog boxes/input functions such as INPUTDLG, QUESTDLG, INPUT?

This function or dialog that times-out after a given period and returns default answers.

Answer 1

[MathWorks Support Team]

Currently, there is no built-in command in MATLAB that includes a time-out period for the dialog/input prompt.

As a workaround, you can use the TIMER function to close the dialog at time-out. An example is provided below.

function varargout = timeoutDlg(dlg, delay, varargin)

% Dialog function with timeout property

% dlg is a handle to the dialog function to be called

% delay is the length of the delay in seconds

% other input arguments as required by the dialog

% EXAMPLE FUNCTION-CALL

% To display an input dialog box (REFER MATLAB HELP DOC) with a 

% timeout = 6 second say, the function call would be:

%

% [matrix_size_value, colormap_string] = timeoutdlg(@inputdlg, 6, ...

%                                {'Enter matrix size:','Enter colormap name:'}, ...

%                                'Input for peaks function', 1, {'20','hsv'})

% Setup a timer to close the dialog in a moment

f1 = findall(0, 'Type', 'figures');

t = timer('TimerFcn', {@closeit f1}, 'StartDelay', delay);

start(t);

% Call the dialog

retvals = dlg(varargin{:});

if numel(retvals) == nargout

      varargout = retvals(:);

else

      varargout = cell(1, nargout);

end

% Delete the timer

if strcmp(t.Running, 'on')

       stop(t);

end

delete(t);

function closeit(src, event, f1)

disp('Time out!');

f2 = findall(0, 'Type', 'figure');

fnew = setdiff(f2, f1);

if ishandle(fnew);

      close(fnew);

end

[Kouichi C. Nakamura]

Thank you. It worked with brilliantly with questdlg() as well.

function button = questdlgtimeout(delay, varargin)
% questdlg function with timeout property
%
% Based on timeoutDlg by MathWorks Support Team
% https://uk.mathworks.com/matlabcentral/answers/96229-how-can-i-have-a-dialog-box-or-user-prompt-with-a-time-out-period
%
% button = questdlgtimeout(delay,'qstring')
% button = questdlgtimeout(delay,qstring,title)
% button = questdlgtimeout(delay,qstring,title,default)
% button = questdlgtimeout(delay,qstring,title,str1,str2,default)
% button = questdlgtimeout(delay,qstring,title,str1,str2,str3,default)
% button = questdlgtimeout(delay,qstring,title, ..., options)
%
% INPUT ARGUMENTS
% delay       Duration in second during withich the dialog is maintained
%
% var1,var2,...
%             Accepts input arguments for builtin questdlg. See
%             documentation of questdlg
%
% OUTPUT ARGUMENTS
% button       The dialog has three default buttons, Yes, No, and Cancel.
%              If the user presses one of these three buttons, button is
%              set to the name of the button pressed. If the user presses
%              the close button on the dialog without making a choice,
%              button returns as an empty character vector (''). If the
%              user presses the Return key, button returns with a value of
%              'Yes'.
%
%              If you provide default or options, button will be the
%              default value.
%
%
% See also
% questdlg, timer, scr20170308_154424_questdlgtimeout
%
% Written by Kouichi C. Nakamura Ph.D.
% MRC Brain Network Dynamics Unit
% University of Oxford
% 08-Mar-2017 16:06:58

f1 = findall(0, 'Type', 'figures');
t = timer('TimerFcn', {@closeit f1}, 'StartDelay', delay);
start(t);

dlg = @questdlg;

% Call the dialog
button = dlg(varargin{:});

if isempty(button)
  if length(varargin) >= 3
      if  isstruct(varargin{end})
          button = varargin{end}.Default;
      elseif ischar(varargin{end})

            button = varargin{end};

        else
            error('unexpected syntax')
        end
    else % no default provided
        % leave button empty
    end
end

% Delete the timer
if strcmp(t.Running, 'on')
  stop(t);
end
delete(t);

function closeit(src, event, f1)
disp('Time out');
f2 = findall(0, 'Type', 'figure');
fnew = setdiff(f2, f1);
if ishandle(fnew)
  close(fnew);
end