How to make a buffer-local key binding in Emacs?

Question

I've been working on an Emacs minor mode lately and part of its functionality was displaying images in separate buffers. So far I've been using a function like this:

(defun create-buffer-with-image (name)
  (let ((buffer (generate-new-buffer name))
        (image (get-svg-for-kanji-code name)))
    (switch-to-buffer buffer)
    (turn-on-iimage-mode)
    (iimage-mode-buffer t)
    (insert-image image)))

and it produces a buffer with the image passed as argument, but closing the buffer requires hitting C-x k and Return, which started to get cumbersome after a while. The way to simplify closing of such transient buffers would be to have a key binding for the kill-this-buffer function, but it would need to be buffer-specific, so as not to mess up anything else. The question is how to make such a binding with the creation of a buffer.

Answer 1

From EmacsWiki: https://www.emacswiki.org/emacs/BufferLocalKeys

For buffer-local keys, you cannot use local-set-key, unless you want to modify the keymap of the entire major-mode in question: local-set-key is local to a major-mode, not to a buffer.

For buffer-local modifications, use this instead:

(use-local-map (copy-keymap foo-mode-map))
(local-set-key "d" 'some-function)

Written by:  TiagoSaboga

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To inspect the change, type C-h b aka M-x describe-bindings

Answer 2

I'd suggest you add a call to special-mode after the call to switch-to-buffer. In the longer run, you'll want to use your own major mode, so you'd do:

(define-derived-mode my-image-mode special-mode "MyImage"
  "My own major mode to display images."
  ;; We could add more things here
  )

(defun create-buffer-with-image (name)
  (with-current-buffer (generate-new-buffer name)
    (my-image-mode)
    (let ((image (get-svg-for-kanji-code name)))
      (turn-on-iimage-mode)
      (iimage-mode-buffer t)
      (insert-image image)
      (pop-to-bffer (current-buffer)))))