Ubuntu – Emulate mouse click when hitting a key

bashkeyboardmouseshortcut-keystouchpad

I am trying to emulate left-mouse-down when Home key is down and left-mouse-up when Home key is released.

The reason behind that is my touchpad's buttons are terrible and I like to use the track-point (red nipple) with left mouse click for highlight (copy) text. Instead of using the touchpad's button I want to use the 'Home' key. I am able to emulate the mouse-down part but I don't know how to release the click when the 'Home' key is released.

Here is what I have so for. first I use the xbindkeys tool. I added this entry to the .xbindkeysrc:

"~/bin/mouse-click"
  m:0x0 + c:110

mouse-click is this bash script:

#!/bin/bash
xdotool mousedown 1

The problem is the click is never being released so I need to find a way to detect the release of the 'Home'. Here is the script I am trying to write. The comments describe what I am trying to do:

#!/bin/bash

# not sure how to do that:
exit if Home key is in a pressed state (to avoid more mousedown actions)

xdotool mousedown 1

# not sure how to do that: (if Home key is released, release the mouse click)
while xinput query-state <device name> | grep -Flq 'key[9]=up'
xdotool mouseup 1

So That's what I am trying to figure out:

Query the state of 'Home' key (pressed or not).
Listen to keyboard events and detect a release of 'Home' key.

If there are better approach to achieve that, I would love to hear about them.
Thanks!

Edit: the solution is one line: xmodmap -e "keycode 115 = Pointer_Button2"
so now my Home key is doing left click and behave just as if I hit the mouse click and I can keep the key pressed and it highlights (copy) as expected.

I also mapped my End key to be middle click, so I can use it to paste:
xmodmap -e "keycode 110 = Pointer_Button1"

Best Answer

The solution is

xmodmap -e "keycode 115 = Pointer_Button2"

Now my Home key is doing left click and behaves just as if I hit the mouse click and I can keep the key pressed and it highlights (copies) as expected.

I also mapped my End key to be middle click, so I can use it to paste:

xmodmap -e "keycode 110 = Pointer_Button1"

Note that it is necessary to have "mousekeys" (mouse emulation using the numeric keypad) enabled for this to work. "mousekeys" can be toggled by pressing Shift+NumLock or set explicitly by running:

dconf write /org/gnome/desktop/a11y/keyboard/mousekeys-enable true
dconf write /org/gnome/desktop/a11y/keyboard/mousekeys-enable false

Related Solutions

Ubuntu – mouse sometimes doubleclicks when i click once

OK after extensive testing using xev on the affected machine, and switching around between various mice on various systems, I believe I have solved this problem. Of course YMMV.

My solution: it is a broken mouse.

More precisely, the connector activated when clicking is a bit old or dirty or something, and sometimes, when holding the button down, the connection is made, and then momentarily broken, and then made again, causing the double click.

Objection: But the mouse works fine when I plug it into my Windows machine!

Counter: Wouldn't it be just trivial to put into a driver, or an OS, the following line of pseudocode: "if the user unclicks the mouse and then clicks it again within 0.05 seconds, then that's probably a dirty connector, so let's just ignore that". Thus isn't it possible that if you switch your mouse to another computer running another OS and/or using another driver on different hardware (even with the same OS you could well be using different hardware, right?), you could get different results?

Objection: But I tried another old mouse and it exhibited the same problem!

Counter: amazing how two old mice from the same company can both break in the same way, eh? And you never noticed because that second old mouse you tried was exhibiting no problems when plugged into different hardware (see previous counter).

If you really don't believe your mouse is broken, then test it:

$ xev

and then find the square with the black background, click in it, and watch the output. Do you definitely, always, get one clean "click" and nothing else? I would often get a clean click but occasionally a "bounce "(click unclick click). Even better perhaps:

$ xev | grep ButtonRelease

Now stick the mouse into the square with the black outline (or anywhere in that window) and click and unclick 20 times. You should get a "ButtonRelease" line every time you release the button, and never otherwise. I would occasionally get one when I clicked.

Nightmare over.

Ubuntu – How to make shortcut keys move the mouse, as an alternative to the touchpad

Scripted alternative to Universal access (to move the mouse)

Not 100% exactly like you describe, nevertheless an alternative for using the mouse or touchpad. The answer below in fact is an almost exact copy of an answer I posted a long time ago on this question. I deleted it however, since I never had the chance to find out if it was what OP was looking for (no response at all).

In your case, since you only want to use it to move the mouse, you can leave out a number of shortcut keys (the last three) which will also prevent the most "risky" options. The scripted options should work fine any way, without risks on conflicting situations.

Mouse Keys alternative

As mentioned, the script offers basic mouse functionality, as an alternative to the default Mouse Keys- option in System Settings > Universal Access. Unlike Mouse Keys, the mouse pointer is moved (either x- or y wise) by repeated clicks, in two modes:

bigger steps (as it is set now: 50px)
smaller steps to "finish" (as it is set now: 3 px)

To my own surprise, I found it reasonably comfortable to use. It is definitely not the same level as a "real" mouse, but (much) more comfortable than the use of Mouse Keys, at least in my experience. After five minutes to get used to it, I was able to perform practically all "normal" actions; opening applications, drag windows, edit text etc.

Disadvantage

There is however a downside to mention:

Unlike Mouse Keys, the setup does not "claim" the NumPad exclusively. The disadvantage of that is that there is a bigger chance of key clashes, especially with the left/right click and hold the left click -functionality. Although I did not run into insurmountable situations, you might run into some conflicts, and being familiar with general shortcut keys is an advantage.
You will have to try and see if it works for you.

The setup

The script needs xdotool:
```
sudo apt-get install xdotool
```
Disable mouse keys (most likely it already is)

Copy the script below into an empty file, save it as mouse(no extension) in ~/bin (create the directory if needed).

#!/usr/bin/env python3
import subprocess
import sys
#--- Don't change these lines:
direction = sys.argv[1]
speed = sys.argv[2]
#--- Change the steps below if you'd like to
big_step = 50
small_step = 3
#---

step = big_step if speed == "fast" else small_step
step = -step if direction == "left" or direction == "up" else step
get = lambda cmd: subprocess.check_output(cmd).decode("utf-8")

def move():
    coords = [int(it.split(":")[1]) for it in get(["xdotool", "getmouselocation"]).split()[:2]]
    if direction in ["left", "right"]:
        cmd = "xdotool", "mousemove", str(coords[0]+step), str(coords[1])
    elif direction in ["up", "down"]:
        cmd = "xdotool", "mousemove", str(coords[0]), str(coords[1]+step)
    subprocess.call(cmd)
move()

Make the script executable.
If you just created ~/bin, either log out/in, or run source ~/.profile, to make the directory "visible" in $PATH.
Now add a number of shortcut keys. All shortcut keys as I set it up are aiming on the use of the NumPad, in combination with Shift+Ctrl (fast move), Ctrl (slow move, mouse left click), Ctrl+Super, (right click, mouse down).

Add the following shortcut keys: System Settings > "Keyboard" > "Shortcuts" > "Custom Shortcuts". Click the "+" and add the commands (11 in total, including mouse keys):
```
mouse left fast 
```
key combination: Shift+Ctrl+Num Left
```
mouse right fast    
```
key combination: Shift+Ctrl+Num Right
```
mouse up fast       
```
key combination: Shift+Ctrl+Num Up
```
mouse down fast     
```
key combination: Shift+Ctrl+Num Down

And:
```
mouse left slow 
```
key combination: Ctrl+Num Left
```
mouse right slow 
```
key combination: Ctrl+Num Right
```
mouse up slow       
```
key combination: Ctrl+Num Up
```
mouse down slow     
```
key combination: Ctrl+Num Down

Additionally, I set shortcut keys for:
- left-click:
```
xdotool click 1 
```
key combination: Ctrl+*
- right-click:
```
xdotool click 3 
```
key combination: Ctrl+Super+*)
- hold left click (e.g. to grab, use click to release):
```
xdotool mousedown 1 
```
key combination: Ctrl+Super+/)