Get "RETURN" key press using "CurrentCharacter" returns and empty string.

Dear all,

I am tryiing to write a GUI in which the user must enter the command (RETURN or DELETE) from the keyboard. For that purpose, I wrote a code where I set the 'KeyPressFcn' to read the key pressed by the user. The mais problem is that when the user types "RETURN" or "DELETE" all I get is an empty string.

Here is the code:

function getKey(axeshandle)

fig = ancestor(axeshandle, 'figure');
set(fig, 'KeyPressFcn', @keyRead);
uiwait(fig);

      function keyRead(src, callback)
          key = get(fig, 'CurrentCharacter');
          strcmp(key, 'return')
          class(key)
      end

end

Any idea on how can I solve this?

Answer 1

[Geoff Hayes]

Gabriel - to be clear, are you expecting the user to type in RETURN or DELETE or press the return or delete keys on the keyboard? The following line of code

 key = get(fig, 'CurrentCharacter');

will just return the character of the pressed key. For a button like return, key will be an empty character.

If you want to capture the input from the keyboard, then I would change your callback to

function keyRead(src, event)
    key = event.Key;
    fprintf('The key being pressed is: %s\n', key);
end

By the way, I'm not sure why you have the uiwait or are using the f instead of fig. What is the intent of the former, and is the latter a typo?