diff options
author | Lars Ingebrigtsen <larsi@gnus.org> | 2019-07-30 15:21:29 +0200 |
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committer | Lars Ingebrigtsen <larsi@gnus.org> | 2019-07-30 15:21:29 +0200 |
commit | b75fb81e362b8afbf37da0d2480676269430694c (patch) | |
tree | 82e1f67de4a7f4340b46a2219ed573c9be1c1def /lisp/button.el | |
parent | 99156a03bfee8304cf2644470dceb668e6262c98 (diff) | |
download | emacs-b75fb81e362b8afbf37da0d2480676269430694c.tar.gz |
Extend button.el to take callback data
* doc/lispref/display.texi (Button Buffer Commands)
(Button Buffer Commands): Document this.
* lisp/button.el (backward-button, forward-button): Accept a
NO-ERROR parameter.
(button-activate): Make it possible to have specific data in the
callback action.
Diffstat (limited to 'lisp/button.el')
-rw-r--r-- | lisp/button.el | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/lisp/button.el b/lisp/button.el index 921e84dfa68..ca6f0d3b6ea 100644 --- a/lisp/button.el +++ b/lisp/button.el @@ -235,15 +235,19 @@ The action can either be a marker or a function. If it's a marker then goto it. Otherwise if it is a function then it is called with BUTTON as only argument. BUTTON is either an overlay, a buffer position, or (for buttons in the mode-line or -header-line) a string." +header-line) a string. + +If BUTTON has a `button-data' value, call the function with this +value instad of BUTTON." (let ((action (or (and use-mouse-action (button-get button 'mouse-action)) - (button-get button 'action)))) + (button-get button 'action))) + (data (button-get button 'button-data))) (if (markerp action) (save-selected-window (select-window (display-buffer (marker-buffer action))) (goto-char action) (recenter 0)) - (funcall action button)))) + (funcall action (or data button))))) (defun button-label (button) "Return BUTTON's text label." @@ -324,6 +328,10 @@ using `make-text-button'. Note, however, that if there is an existing face property at the site of the button, the button face may not be visible. You may want to use `make-button' in that case. +If the property `button-data' is present, it will later be used +as the argument for the `action' callback function instead of the +default argument, which is the button itself. + BEG can also be a string, in which case it is made into a button. Also see `insert-text-button'." @@ -462,13 +470,17 @@ return t." (button-activate button use-mouse-action) t)))) -(defun forward-button (n &optional wrap display-message) +(defun forward-button (n &optional wrap display-message no-error) "Move to the Nth next button, or Nth previous button if N is negative. If N is 0, move to the start of any button at point. If WRAP is non-nil, moving past either end of the buffer continues from the other end. If DISPLAY-MESSAGE is non-nil, the button's help-echo string is displayed. Any button with a non-nil `skip' property is skipped over. + +If NO-ERROR, return nil if no further buttons could be found +instead of erroring out. + Returns the button found." (interactive "p\nd\nd") (let (button) @@ -497,22 +509,28 @@ Returns the button found." (unless (button-get button 'skip) (setq n (1- n))))))) (if (null button) - (user-error (if wrap "No buttons!" "No more buttons")) + (if no-error + nil + (user-error (if wrap "No buttons!" "No more buttons"))) (let ((msg (and display-message (button-get button 'help-echo)))) (when msg (message "%s" msg))) button))) -(defun backward-button (n &optional wrap display-message) +(defun backward-button (n &optional wrap display-message no-error) "Move to the Nth previous button, or Nth next button if N is negative. If N is 0, move to the start of any button at point. If WRAP is non-nil, moving past either end of the buffer continues from the other end. If DISPLAY-MESSAGE is non-nil, the button's help-echo string is displayed. Any button with a non-nil `skip' property is skipped over. + +If NO-ERROR, return nil if no further buttons could be found +instead of erroring out. + Returns the button found." (interactive "p\nd\nd") - (forward-button (- n) wrap display-message)) + (forward-button (- n) wrap display-message no-error)) (provide 'button) |