How do I get MatLab to respond to keyboard?

I would like to run some code if the letter "r" is pressed on the keyboard. How would I do this? And what syntax would be used? And should I store the code I would like to run in a separate editor?

Thank you!

[Adam]

Take a look at KeyPressFcn in Figure properties.

Answer 1

[Walter Roberson]

The methods are the same as for http://www.mathworks.com/matlabcentral/answers/307934-how-to-increase-a-value-with-the-arrow-keys#answer_239631

[Emily Smith]

I am still a little confused. I want MatLab to run some code displaying an image when i press the letter "r" on the keyboard. so far this is what I have come up with:

b = uicontrol('Style','pushbutton','Callback',@callbackfunction);

the code i want to run i saved as "callbackfunction" in an editor

Thanks!

[Walter Roberson]

set(gcf, 'Windowkeypressfcn', @callbackfunction)

function callbackfunction(src, event)
   strcmp(event.Character, 'r')
     imshow('TheImageToDisplay.jpg');
   end

[Emily Smith]

for some reason it is coming up with an error that "functions definitions are not permitted in this context" and also the code for displaying the image is already in the editor i saved as "callbackfunction"

[Adam]

Change your script into a function. You cannot define functions inside a script.

Just put

function yourFilename

at the top, where obviously 'yourFilename' should be replaced by whatever you called the file (without the .m extension)

[Emily Smith]

in the editor I named "callbackfunction" the first line of code is:

    function callbackfunction

and then in a seperate editor when I try to run the code:

    set(gcf, 'Windowkeypressfcn', @callbackfunction)

    function callbackfunction(src, event)
    strcmp(event.Character, 'r')
    end

it says it has an error

[Emily Smith]

sorry for all the questions by the way, I'm new at this

[Walter Roberson]

In the editor for callbackfunction.m change the code to be

function callbackfunction(src, event)
  if strcmp(event.Character, 'r')
    imshow('TheImageToDisplay.jpg');
  end

Then in the code that needs to tell MATLAB to allow that callback to be used, put in

    set(gcf, 'Windowkeypressfcn', @callbackfunction)