Add file

1 files changed, 120 insertions, 0 deletions

diff --git a/spinner.el b/spinner.el
new file mode 100644
index 0000000..bd96a8e
--- /dev/null
+++ b/spinner.el
@@ -0,0 +1,120 @@
+;;; spinner.el --- Mode-line spinner for operations in progress  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2015  Artur Malabarba
+
+;; Author: Artur Malabarba <bruce.connor.am@gmail.com>
+;; Version: 1.0
+;; Keywords: processes mode-line
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Run `(spinner-start)' to see the effect.
+
+
+;;; Code:
+
+(defconst spinner-types
+  '((line . ["┤" "┘" "┴" "└" "├" "┌" "┬" "┐"])
+    (progress-bar . ["[    ]" "[=   ]" "[==  ]" "[=== ]" "[====]"])
+    (vertical . ["▁" "▃" "▄" "▅" "▆" "▇" "█" "▇" "▆" "▅" "▄" "▃"])
+    (horizontal . ["▉" "▊" "▋" "▌" "▍" "▎" "▏" "▎" "▍" "▌" "▋" "▊" "▉"])
+    (minibox . ["▖" "▘" "▝" "▗"])
+    (triangle . ["◢" "◣" "◤" "◥"])
+    (box-in-box . ["◰" "◳" "◲" "◱"])
+    (box-in-circle . ["◴" "◷" "◶" "◵"])
+    (half-circle . ["◐" "◓" "◑" "◒"])
+    (arrow . ["←" "↖" "↑" "↗" "→" "↘" "↓" "↙"])) 
+  "Predefined alist of spinners.
+Each car is a symbol identifying the spinner, and each cdr is a
+vector, the spinner itself.")
+
+(defvar spinner-current nil
+  "Spinner curently being displayed on the mode-line.")
+(make-variable-buffer-local 'spinner-current)
+
+(defun spinner-stop ()
+  "Stop the current buffer's spinner."
+  (when (timerp spinner--timer)
+    (cancel-timer spinner--timer))
+  (setq spinner--timer nil
+        spinner-current nil)
+  (setq mode-line-format
+        (remove 'spinner--mode-line-construct mode-line-format)))
+
+(defconst spinner--mode-line-construct
+  '((spinner-current
+     (" "
+      (:eval (elt spinner-current
+                  (% (cadr (current-time))
+                     (length spinner-current)))))
+     (spinner--timer
+      (:eval (spinner-stop)))))
+  "Construct used to display the spinner.")
+(put 'spinner--mode-line-construct 'risky-local-variable t)
+
+(defvar spinner--timer nil
+  "Holds the timer being used on the current buffer.")
+(make-variable-buffer-local 'spinner--timer)
+
+(defun spinner-start (&optional type)
+  "Start a mode-line spinner of given TYPE.
+Spinners are buffer local.  Call `spinner-stop' in the same buffer
+to stop it.
+
+If TYPE is nil, use the first element of `spinner-types'.
+If TYPE is `random', use a random element of `spinner-types'.
+If it is a symbol, it specifies an element of `spinner-types'.
+If it is a vector, it used as the spinner.
+If it is a list, it should be a list of symbols, and a random one
+is chosen as the spinner type."
+  ;; Choose type.
+  (setq spinner-current
+        (cond
+         ((vectorp type) type)
+         ((not type) (cdr (car spinner-types)))
+         ((eq type 'random)
+          (cdr (elt spinner-types
+                    (random (length spinner-types)))))
+         ((listp type)
+          (cdr (assq (elt type (random (length type)))
+                     spinner-types)))
+         ((symbolp type) (cdr (assq type spinner-types)))
+         (t (error "Unknown spinner type: %s" type))))
+  
+  ;; Maybe add to mode-line.
+  (unless (memq 'spinner--mode-line-construct mode-line-format)
+    (setq mode-line-format (copy-list mode-line-format))
+    (let ((cell (memq 'mode-line-buffer-identification mode-line-format)))
+      (if cell
+          (setcdr cell (cons 'spinner--mode-line-construct (cdr cell)))
+        (setcdr (last mode-line-format) '(spinner--mode-line-construct)))))
+
+  ;; Create timer.
+  (when (timerp spinner--timer)
+    (cancel-timer spinner--timer))
+  (let ((buffer (current-buffer))
+        ;; Create the timer as a lex variable so it can cancel itself.
+        (timer (run-at-time t 1 #'ignore)))
+    (timer-set-function
+     timer (lambda ()
+             (if (buffer-live-p buffer)
+                 (with-current-buffer buffer
+                   (force-mode-line-update))
+               (ignore-errors (cancel-timer timer)))))
+    (setq spinner--timer timer))) 
+
+(provide 'spinner)
+;;; spinner.el ends here