Re: Fix some tooltip related problems

[Alan Third <alan@idiocy.org>]

[-- Attachment #1: Type: text/plain, Size: 1538 bytes --]

On Wed, Jan 10, 2018 at 01:02:42PM -0800, Drew Adams wrote:
>    Given that limitation, I repeat the question: Can't we
>    use a ("normal") Emacs frame, where things such as faces
>    do work, to implement tooltips?

I believe it should be possible now we have undecorated frames
available. I’ve made a (really bad) attempt at proving we can do it.
Patch attached.

My emacs lisp skills are rather bad, so I couldn’t work out how to get
tooltip-hide to work, or how exactly I should set the size of the
tooltip, or how to not display the modeline, but it kind of works...
Someone who knows what they’re doing should be able to make a better
fist of it than me.

One possible issue is that it might be difficult to stop frame‐based
tooltips from crossing screens on multi‐monitor setups. I know we fix
that in Objective‐C code in NS, I don’t know if lisp knows enough
about screen geometry to get round it.

(BTW, I just noticed that under NS toolbar tooltips are native, while
other tooltips aren’t.)

>    Did someone have to explain to you what a dimmed menu item
>    is all about?  Is that inherently confusing the first time
>    someone sees it?  I think not.  A tooltip with dimmed text
>    is no more confusing.

I disagree, a menu item is interactive, or not if it’s dimmed, so it
becomes clear quite quickly what dimming means. A dimmed tooltip is
still a tooltip, just a bit harder to read. It takes further action to
discover that the information its giving you isn’t currently usable.

-- 
Alan Third

[-- Attachment #2: 0001-Implement-rubbish-frame-base-tooltips.patch --]
[-- Type: text/plain, Size: 2928 bytes --]

From 36a9a38619d2b1658a2ee4b96faa89a2b17843ae Mon Sep 17 00:00:00 2001
From: Alan Third <alan@idiocy.org>
Date: Wed, 10 Jan 2018 23:03:36 +0000
Subject: [PATCH] Implement rubbish frame-base tooltips

---
 lisp/tooltip.el | 45 +++++++++++++++++++++++++++++++++++++++------
 1 file changed, 39 insertions(+), 6 deletions(-)

diff --git a/lisp/tooltip.el b/lisp/tooltip.el
index 81df229a13..2117d2aaa3 100644
--- a/lisp/tooltip.el
+++ b/lisp/tooltip.el
@@ -190,6 +190,8 @@ tooltip-hide-time
 
 (defvar gud-tooltip-mode) ;; Prevent warning.
 
+(defvar tooltip-frame)
+
 ;;; Event accessors
 
 (defun tooltip-event-buffer (event)
@@ -262,12 +264,41 @@ tooltip-show
 	    (setf (alist-get 'border-color params) fg))
 	  (when (stringp bg)
 	    (setf (alist-get 'background-color params) bg))
-	  (x-show-tip (propertize text 'face 'tooltip)
-		      (selected-frame)
-		      params
-		      tooltip-hide-delay
-		      tooltip-x-offset
-		      tooltip-y-offset))
+          (let* ((buf (get-buffer-create "*tooltip*"))
+                 (frame (make-frame
+                         (append
+                          `((no-focus-on-map . t)
+                            (undecorated . t)
+                            (tool-bar-lines . 0)
+	                    (menu-bar-lines . 0)
+	                    (minibuffer . nil)
+	                    (vertical-scroll-bars . nil)
+	                    (horizontal-scroll-bars . nil)
+	                    (left-fringe . 0)
+	                    (right-fringe . 0))
+                          (if (not (alist-get 'left params))
+                              `((left . ,(+ tooltip-x-offset (car (mouse-absolute-pixel-position)))))
+                            '())
+                          (if (not (alist-get 'top params))
+                              `((top . ,(+ tooltip-y-offset (cdr (mouse-absolute-pixel-position)))))
+                            '())
+                          params))))
+            (with-current-buffer buf
+              (erase-buffer)
+              (insert (propertize text 'face 'tooltip)))
+            (set-window-buffer (frame-root-window frame) buf)
+            (setq tooltip-frame frame)
+            (run-at-time tooltip-hide-delay nil
+                         (lambda () (delete-frame tooltip-frame))))
+
+
+	  ;; (x-show-tip (propertize text 'face 'tooltip)
+	  ;;             (selected-frame)
+	  ;;             params
+	  ;;             tooltip-hide-delay
+	  ;;             tooltip-x-offset
+	  ;;             tooltip-y-offset))
+          )
       (error
        (message "Error while displaying tooltip: %s" error)
        (sit-for 1)
@@ -279,6 +310,8 @@ tooltip-hide
   "Hide a tooltip, if one is displayed.
 Value is non-nil if tooltip was open."
   (tooltip-cancel-delayed-tip)
+  ;; (if (not (null tooltip-frame))
+  ;;     (delete-frame tooltip-frame))
   (when (x-hide-tip)
     (setq tooltip-hide-time (float-time))))
 
-- 
2.14.3