Prevent mouse click from changing cursor position while in insert mode

Question

I work on a laptop most of the time and it happens somewhat often that while inserting some text (in evil mode) I will accidentally hit the touchpad with my thumb, changing the cursor position and causing the next few words to be inserted into some unrelated paragraph. The somewhat annoying thing is that undo is usually of no help here, because the last saved undo state is whenever I entered insert mode and I might have written several sentences since then that I don't want to lose. I'd rather not completely disable use of the mouse, so I'm hoping to implement one of the following acceptable fixes:

• Don't allow mouse clicks to change position while in evil insert mode, only in normal mode (this sounds the simplest).
• Update the undo state whenever I change cursor position with the mouse, if there is a callback for that.

Are either of these possible?

Answer 1

I appended this to my .emacs to disable the changing of point (cursor) on tap: (defun mouse-set-point (event))

What it does is basically it changes the definition of the mouse-set-point function to nothing so that the function does not change the point (position in the buffer).

If you want to go back to the default definition, remove the line or uncomment it.

This will sometimes make the clicking of the link hard so fiddle with the variable: mouse-1-click-follows-link to see what suits you best.

Answer 2

Two potential answers:

1) This is not exactly an emacs fix for your question, and may or may not apply in your situation. The exact steps will depend on your os and desktop environment:

If you're using linux with one of many desktop environments (gnome3, MATE, openbox, etc.) there is a setting under "mouse" settings (sometimes on the "touchpad" tab of the mouse-settings window) that says something to the effect of "disable touchpad while typing" (see also "synaptic"). This will not help if you pause typing and then touch the touchpad.

2) emacs solution: Stolen directly from: https://www.reddit.com/r/emacs/comments/a799um/how_to_disable_mouse_in_emacs/

This involves setting the keybinding for the mouse to do nothing (nil):

(use-package evil
  :ensure t
  :diminish evil
  :init (evil-mode 1)
  (setq evil-insert-state-cursor '((bar . 1) "white")
  evil-visual-state-cursor '(box "dark orange")
  evil-normal-state-cursor '(box "white"))
  :bind (:map
   evil-insert-state-map
   ([S-left]     . windmove-left)
   ([S-right]    . windmove-right)
   ([S-up]     . windmove-up)
   ([S-down]    . windmove-down)
   ("<down-mouse-1>" . nil)
   ("<mouse-1>" . nil)
   ("<down-mouse-3>" . nil)
   ("<mouse-3>" . nil)
   ("SPC" . nil)
   :map
   evil-normal-state-map
   (";" . evil-ex)
   (":"   .       evil-repeat-find-char)
   ("<down-mouse-1>" . nil)
   ("<mouse-1>" . nil)
   ("<down-mouse-3>" . nil)
   ("<mouse-3>" . nil)
   ("SPC" . nil)
   :map    evil-motion-state-map
   ([S-left]     . windmove-left)
   ([S-right]    . windmove-right)
   ([S-up]     . windmove-up)
   ([S-down]    . windmove-down)
   ("<down-mouse-1>" . nil)
   ("<mouse-1>" . nil)
   ("<down-mouse-3>" . nil)
   ("<mouse-3>" . nil)
   ("SPC" . nil)
   ))