Parallel Problem: Get keyboard input in 60 sec, otherwise jump out

Hi to all, I recently encountered a problem. I want to get the keyboard input and read it and put something on the screen if the user puts a cerntain key such as 'q'. However, if the user doesn't put in anything in 20 sec, I want the time counter to start again. This procedure loops over for 60 times.

Can anyone help me with this? Thank you very much!

Answer 1

[Sven]

Shijia, you can do something like this using callbacks. Here's an example using figure callbacks. Save it as myFunction.m and see if you can follow what it does:

function myFunction

figure('KeyPressFcn',@kp);
ticCount = 0;
lastTic = 0;
startTimer()

      function startTimer()
          ticCount = ticCount+1;
          if ticCount>10
              fprintf('We''ve already reached the end!!!!\n')
              return;
          end
          lastTic = tic;
          fprintf('Starting the timer for time number %d\n',ticCount)
          justWait(5)
      end
      function kp(~,evnt)
          fprintf('User pressed %s\n',evnt.Character)
          if evnt.Character == 'q'
              fprintf('It took the user %g seconds...\n', toc(lastTic))
              startTimer()
          end
      end
      function justWait(len)
          oldTicCount = ticCount;
          fprintf('About to wait for %g seconds...\n',len)
          pause(len)
          if ticCount==oldTicCount
              fprintf('Nothing happened for %g seconds...\n',len)
              startTimer()
          end
      end
  end