(momentary): New face.

(momentary-string-display): Display the string via a temporary
overlay using the new face, instead of inserting it in the buffer.

2 files changed, 25 insertions, 29 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 6cb365666a4..e4ea386e686 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2007-01-04  Kevin Rodgers  <kevin.d.rodgers@gmail.com>
+
+        * subr.el (momentary): New face.
+        (momentary-string-display): Display the string via a temporary
+        overlay using the new face, instead of inserting it in the buffer.
+
 2007-01-04  Andreas Schwab  <schwab@suse.de>
 
         * progmodes/ebrowse.el (ebrowse-global-prefix-key): Fix typo in
diff --git a/lisp/subr.el b/lisp/subr.el
index c98e14b6334..31d220a8dd3 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1884,6 +1884,11 @@ menu bar menus and the frame title."
   (if all (save-excursion (set-buffer (other-buffer))))
   (set-buffer-modified-p (buffer-modified-p)))
 
+(defface momentary
+  '((t (:inherit mode-line)))
+  "Face for momentarily displaying text in the current buffer."
+  :group 'display)
+
 (defun momentary-string-display (string pos &optional exit-char message)
   "Momentarily display STRING in the buffer at POS.
 Display remains until next event is input.
@@ -1895,32 +1900,21 @@ input (as a command if nothing else).
 Display MESSAGE (optional fourth arg) in the echo area.
 If MESSAGE is nil, instructions to type EXIT-CHAR are displayed there."
   (or exit-char (setq exit-char ?\s))
-  (let ((inhibit-read-only t)
-        ;; Don't modify the undo list at all.
-        (buffer-undo-list t)
-        (modified (buffer-modified-p))
-        (name buffer-file-name)
-        insert-end)
+  (let ((momentary-overlay (make-overlay pos pos nil t)))
+    (overlay-put momentary-overlay 'before-string
+                 (propertize string 'face 'momentary))
     (unwind-protect
         (progn
-          (save-excursion
-            (goto-char pos)
-            ;; To avoid trouble with out-of-bounds position
-            (setq pos (point))
-            ;; defeat file locking... don't try this at home, kids!
-            (setq buffer-file-name nil)
-            (insert-before-markers string)
-            (setq insert-end (point))
-            ;; If the message end is off screen, recenter now.
-            (if (< (window-end nil t) insert-end)
-                (recenter (/ (window-height) 2)))
-            ;; If that pushed message start off the screen,
-            ;; scroll to start it at the top of the screen.
-            (move-to-window-line 0)
-            (if (> (point) pos)
-                (progn
-                  (goto-char pos)
-                  (recenter 0))))
+          ;; If the message end is off screen, recenter now.
+          (if (< (window-end nil t) (+ pos (length string)))
+              (recenter (/ (window-height) 2)))
+          ;; If that pushed message start off the screen,
+          ;; scroll to start it at the top of the screen.
+          (move-to-window-line 0)
+          (if (> (point) pos)
+              (progn
+                (goto-char pos)
+                (recenter 0)))
           (message (or message "Type %s to continue editing.")
                    (single-key-description exit-char))
           (let (char)
@@ -1940,11 +1934,7 @@ If MESSAGE is nil, instructions to type EXIT-CHAR are displayed there."
               (or (eq char exit-char)
                   (eq char (event-convert-list exit-char))
                   (setq unread-command-events (list char))))))
-      (if insert-end
-          (save-excursion
-            (delete-region pos insert-end)))
-      (setq buffer-file-name name)
-      (set-buffer-modified-p modified))))
+      (delete-overlay momentary-overlay))))
 
 
 ;;;; Overlay operations