\f
;; Drag and drop support.
(defcustom mouse-drag-and-drop-region nil
- "If non-nil, dragging the mouse drags the region, if that exists.
-If the value is a modifier, such as `control' or `shift' or `meta',
-then if that modifier key is pressed when dropping the region, region
-text is copied instead of being cut."
+ "If non-nil, dragging the mouse drags the region, if it exists.
+If the value is a modifier, such as `control' or `shift' or
+`meta', then if that modifier key is pressed when dropping the
+region, text is copied instead of being cut."
:type `(choice
(const :tag "Disable dragging the region" nil)
,@(mapcar
:version "26.1"
:group 'mouse)
+(defcustom mouse-drag-and-drop-region-cut-when-buffers-differ nil
+ "If non-nil, cut text also when source and destination buffers differ.
+If this option is nil, `mouse-drag-and-drop-region' will leave
+the text in the source buffer alone when dropping it in a
+different buffer. If this is non-nil, it will cut the text just
+as it does when dropping text in the source buffer."
+ :type 'boolean
+ :version "26.1"
+ :group 'mouse)
+
+(defcustom mouse-drag-and-drop-region-show-tooltip 256
+ "If non-nil, text is shown by a tooltip in a graphic display.
+If this option is nil, `mouse-drag-and-drop-region' does not show
+tooltips. If this is t, it shows the entire text dragged in a
+tooltip. If this is an integer (as with the default value of
+256), it will show that many characters of the dragged text in
+a tooltip."
+ :type 'integer
+ :version "26.1"
+ :group 'mouse)
+
+(defcustom mouse-drag-and-drop-region-show-cursor t
+ "If non-nil, move point with mouse cursor during dragging.
+If this is nil, `mouse-drag-and-drop-region' leaves point alone.
+Otherwise, it will move point together with the mouse cursor and,
+in addition, temporarily highlight the original region with the
+`mouse-drag-and-drop-region' face."
+ :type 'boolean
+ :version "26.1"
+ :group 'mouse)
+
+(defface mouse-drag-and-drop-region '((t :inherit region))
+ "Face to highlight original text during dragging.
+This face is used by `mouse-drag-and-drop-region' to temporarily
+highlight the original region when
+`mouse-drag-and-drop-region-show-cursor' is non-nil."
+ :version "26.1"
+ :group 'mouse)
+
(defun mouse-drag-and-drop-region (event)
"Move text in the region to point where mouse is dragged to.
The transportation of text is also referred as `drag and drop'.
variable `mouse-drag-and-drop-region' is that modifier, the text
is copied instead of being cut."
(interactive "e")
- (require 'tooltip)
- (let ((start (region-beginning))
- (end (region-end))
- (point (point))
- (buffer (current-buffer))
- (window (selected-window))
- value-selection)
- (track-mouse
- ;; When event was click instead of drag, skip loop
- (while (progn
- (setq event (read-event))
- (or (mouse-movement-p event)
- ;; Handle `mouse-autoselect-window'.
- (eq (car-safe event) 'select-window)))
- (unless value-selection ; initialization
- (delete-overlay mouse-secondary-overlay)
- (setq value-selection (buffer-substring start end))
- (move-overlay mouse-secondary-overlay start end)) ; (deactivate-mark)
- (ignore-errors (deactivate-mark) ; care existing region in other window
- (mouse-set-point event)
- (tooltip-show value-selection)))
- (tooltip-hide))
- ;; Do not modify buffer under mouse when "event was click",
- ;; "drag negligible", or
- ;; "drag to read-only".
- (if (or (equal (mouse-posn-property (event-end event) 'face) 'region) ; "event was click"
- (member 'secondary-selection ; "drag negligible"
- (mapcar (lambda (xxx) (overlay-get xxx 'face))
- (overlays-at (posn-point (event-end event)))))
- buffer-read-only)
- ;; Do not modify buffer under mouse.
+ (let* ((mouse-button (event-basic-type last-input-event))
+ (mouse-drag-and-drop-region-show-tooltip
+ (when (and mouse-drag-and-drop-region-show-tooltip
+ (display-multi-frame-p)
+ (require 'tooltip))
+ mouse-drag-and-drop-region-show-tooltip))
+ (start (region-beginning))
+ (end (region-end))
+ (point (point))
+ (buffer (current-buffer))
+ (window (selected-window))
+ (text-from-read-only buffer-read-only)
+ (mouse-drag-and-drop-overlay (make-overlay start end))
+ point-to-paste
+ point-to-paste-read-only
+ window-to-paste
+ buffer-to-paste
+ cursor-in-text-area
+ no-modifier-on-drop
+ drag-but-negligible
+ clicked
+ value-selection ; This remains nil when event was "click".
+ text-tooltip
+ states
+ window-exempt)
+
+ ;; STATES stores for each window on this frame its start and point
+ ;; positions so we can restore them on all windows but for the one
+ ;; where the drop occurs. For inter-frame drags we'll have to do
+ ;; this for all windows on all visible frames. In addition we save
+ ;; also the cursor type for the window's buffer so we can restore it
+ ;; in case we modified it.
+ ;; https://lists.gnu.org/archive/html/emacs-devel/2017-12/msg00090.html
+ (walk-window-tree
+ (lambda (window)
+ (setq states
+ (cons
+ (list
+ window
+ (copy-marker (window-start window))
+ (copy-marker (window-point window))
+ (with-current-buffer (window-buffer window)
+ cursor-type))
+ states))))
+
+ (ignore-errors
+ (track-mouse
+ ;; When event was "click" instead of "drag", skip loop.
+ (while (progn
+ (setq event (read-key)) ; read-event or read-key
+ (or (mouse-movement-p event)
+ ;; Handle `mouse-autoselect-window'.
+ (eq (car-safe event) 'select-window)))
+ ;; Obtain the dragged text in region. When the loop was
+ ;; skipped, value-selection remains nil.
+ (unless value-selection
+ (setq value-selection (buffer-substring start end))
+ (when mouse-drag-and-drop-region-show-tooltip
+ (let ((text-size mouse-drag-and-drop-region-show-tooltip))
+ (setq text-tooltip
+ (if (and (integerp text-size)
+ (> (length value-selection) text-size))
+ (concat
+ (substring value-selection 0 (/ text-size 2))
+ "\n...\n"
+ (substring value-selection (- (/ text-size 2)) -1))
+ value-selection))))
+
+ ;; Check if selected text is read-only.
+ (setq text-from-read-only (or text-from-read-only
+ (get-text-property start 'read-only)
+ (not (equal
+ (next-single-char-property-change
+ start 'read-only nil end)
+ end)))))
+ (setq window-to-paste (posn-window (event-end event)))
+ (setq point-to-paste (posn-point (event-end event)))
+ ;; Set nil when target buffer is minibuffer.
+ (setq buffer-to-paste (let (buf)
+ (when (windowp window-to-paste)
+ (setq buf (window-buffer window-to-paste))
+ (when (not (minibufferp buf))
+ buf))))
+ (setq cursor-in-text-area (and window-to-paste
+ point-to-paste
+ buffer-to-paste))
+
+ (when cursor-in-text-area
+ ;; Check if point under mouse is read-only.
+ (save-window-excursion
+ (select-window window-to-paste)
+ (setq point-to-paste-read-only
+ (or buffer-read-only
+ (get-text-property point-to-paste 'read-only))))
+
+ ;; Check if "drag but negligible". Operation "drag but
+ ;; negligible" is defined as drag-and-drop the text to
+ ;; the original region. When modifier is pressed, the
+ ;; text will be inserted to inside of the original
+ ;; region.
+ (setq drag-but-negligible
+ (and (eq (overlay-buffer mouse-drag-and-drop-overlay)
+ buffer-to-paste)
+ (< (overlay-start mouse-drag-and-drop-overlay)
+ point-to-paste)
+ (< point-to-paste
+ (overlay-end mouse-drag-and-drop-overlay)))))
+
+ ;; Show a tooltip.
+ (if mouse-drag-and-drop-region-show-tooltip
+ (tooltip-show text-tooltip)
+ (tooltip-hide))
+
+ ;; Show cursor and highlight the original region.
+ (when mouse-drag-and-drop-region-show-cursor
+ ;; Modify cursor even when point is out of frame.
+ (setq cursor-type (cond
+ ((not cursor-in-text-area)
+ nil)
+ ((or point-to-paste-read-only
+ drag-but-negligible)
+ 'hollow)
+ (t
+ 'bar)))
+ (when cursor-in-text-area
+ (overlay-put mouse-drag-and-drop-overlay
+ 'face 'mouse-drag-and-drop-region)
+ (deactivate-mark) ; Maintain region in other window.
+ (mouse-set-point event)))))
+
+ ;; Hide a tooltip.
+ (when mouse-drag-and-drop-region-show-tooltip (tooltip-hide))
+
+ ;; Check if modifier was pressed on drop.
+ (setq no-modifier-on-drop
+ (not (member mouse-drag-and-drop-region (event-modifiers event))))
+
+ ;; Check if event was "click".
+ (setq clicked (not value-selection))
+
+ ;; Restore status on drag to outside of text-area or non-mouse input.
+ (when (or (not cursor-in-text-area)
+ (not (equal (event-basic-type event) mouse-button)))
+ (setq drag-but-negligible t
+ no-modifier-on-drop t))
+
+ ;; Do not modify any buffers when event is "click",
+ ;; "drag but negligible", or "drag to read-only".
+ (let* ((mouse-drag-and-drop-region-cut-when-buffers-differ
+ (if no-modifier-on-drop
+ mouse-drag-and-drop-region-cut-when-buffers-differ
+ (not mouse-drag-and-drop-region-cut-when-buffers-differ)))
+ (wanna-paste-to-same-buffer (equal buffer-to-paste buffer))
+ (wanna-cut-on-same-buffer (and wanna-paste-to-same-buffer
+ no-modifier-on-drop))
+ (wanna-cut-on-other-buffer
+ (and (not wanna-paste-to-same-buffer)
+ mouse-drag-and-drop-region-cut-when-buffers-differ))
+ (cannot-paste (or point-to-paste-read-only
+ (when (or wanna-cut-on-same-buffer
+ wanna-cut-on-other-buffer)
+ text-from-read-only))))
+
(cond
- ;; "drag negligible" or "drag to read-only", restore region.
- (value-selection
- (select-window window) ; In case miss drag to other window
+ ;; Move point within region.
+ (clicked
+ (deactivate-mark)
+ (mouse-set-point event))
+ ;; Undo operation. Set back the original text as region.
+ ((or (and drag-but-negligible
+ no-modifier-on-drop)
+ cannot-paste)
+ ;; Inform user either source or destination buffer cannot be modified.
+ (when (and (not drag-but-negligible)
+ cannot-paste)
+ (message "Buffer is read-only"))
+
+ ;; Select source window back and restore region.
+ ;; (set-window-point window point)
+ (select-window window)
(goto-char point)
(setq deactivate-mark nil)
(activate-mark))
- ;; "event was click"
+ ;; Modify buffers.
(t
- (deactivate-mark)
- (mouse-set-point event)))
- ;; Modify buffer under mouse by inserting text.
- (push-mark)
- (insert value-selection)
- (when (not (equal (mark) (point))) ; on success insert
- (setq deactivate-mark nil)
- (activate-mark)) ; have region on destination
- ;; Take care of initial region on source.
- (if (equal (current-buffer) buffer) ; when same buffer
- (let (deactivate-mark) ; remove text
- (unless (member mouse-drag-and-drop-region (event-modifiers event))
- (kill-region (overlay-start mouse-secondary-overlay)
- (overlay-end mouse-secondary-overlay))))
- (let ((window1 (selected-window))) ; when beyond buffer
- (select-window window)
- (goto-char point) ; restore point on source window
- (activate-mark) ; restore region
- (select-window window1))))
- (delete-overlay mouse-secondary-overlay)))
+ ;; * DESTINATION BUFFER::
+ ;; Insert the text to destination buffer under mouse.
+ (select-window window-to-paste)
+ (setq window-exempt window-to-paste)
+ (goto-char point-to-paste)
+ (push-mark)
+ (insert value-selection)
+ ;; On success, set the text as region on destination buffer.
+ (when (not (equal (mark) (point)))
+ (setq deactivate-mark nil)
+ (activate-mark))
+
+ ;; * SOURCE BUFFER::
+ ;; Set back the original text as region or delete the original
+ ;; text, on source buffer.
+ (if wanna-paste-to-same-buffer
+ ;; When source buffer and destination buffer are the same,
+ ;; remove the original text.
+ (when no-modifier-on-drop
+ (let (deactivate-mark)
+ (delete-region (overlay-start mouse-drag-and-drop-overlay)
+ (overlay-end mouse-drag-and-drop-overlay))))
+ ;; When source buffer and destination buffer are different,
+ ;; keep (set back the original text as region) or remove the
+ ;; original text.
+ (select-window window) ; Select window with source buffer.
+ (goto-char point) ; Move point to the original text on source buffer.
+
+ (if mouse-drag-and-drop-region-cut-when-buffers-differ
+ ;; Remove the dragged text from source buffer like
+ ;; operation `cut'.
+ (delete-region (overlay-start mouse-drag-and-drop-overlay)
+ (overlay-end mouse-drag-and-drop-overlay))
+ ;; Set back the dragged text as region on source buffer
+ ;; like operation `copy'.
+ (activate-mark))
+ (select-window window-to-paste))))))
+
+ ;; Clean up.
+ (delete-overlay mouse-drag-and-drop-overlay)
+
+ ;; Restore old states but for the window where the drop
+ ;; occurred. Restore cursor types for all windows.
+ (dolist (state states)
+ (let ((window (car state)))
+ (when (and window-exempt
+ (not (eq window window-exempt)))
+ (set-window-start window (nth 1 state) 'noforce)
+ (set-marker (nth 1 state) nil)
+ ;; If window is selected, the following automatically sets
+ ;; point for that window's buffer.
+ (set-window-point window (nth 2 state))
+ (set-marker (nth 2 state) nil))
+ (with-current-buffer (window-buffer window)
+ (setq cursor-type (nth 3 state)))))))
\f
;;; Bindings for mouse commands.
projects / emacs.git / commitdiff