Run a lua function on ctrl double click

[strdr4605]

I found this link that shows how to handle double click on a key https://stackoverflow.com/a/44350843/5458200
I am trying to handle ctrl double click but it's not working:

local timer = require("hs.timer")
local eventtap = require("hs.eventtap") 
local keycodes = require("hs.keycodes")
local events = eventtap.event.types --all the event types

timeFrame = 1 --this is the timeframe in which the second press should occur, in seconds
key = 59 --key code for CTRL

--print(keycodes.map["ctrl"]) you can look up the certain keycode by accessing the map

function twoHandler()
    hs.alert("Pressed ` twice!") --the handler for the double press
end

function correctKeyChecker(event) --keypress validator, checks if the keycode matches the key we're trying to detect
    local keyCode = event:getKeyCode()
    return keyCode == key --return if keyCode is key
end

function inTime(time) --checks if the second press was in time
    return timer.secondsSinceEpoch() - time < timeFrame --if the time passed from the first press to the second was less than the timeframe, then it was in time
end

local pressTime, firstDown = 0, false --pressTime was the time the first press occurred which is set to 0, and firstDown indicates if the first press has occurred or not

eventtap.new({ events.keyDown }, function(event) --watch the keyDown event, trigger the function every time there is a keydown
    if correctKeyChecker(event) then --if correct key
        if firstDown and inTime(pressTime) then --if first press already happened and the second was in time
            twoHandler() --execute the handler
        elseif not firstDown or inTime(pressTime) then --if the first press has not happened or the second wasn't in time
            pressTime, firstDown = timer.secondsSinceEpoch(), true --set first press time to now and first press to true
            return false --stop prematurely
        end
    end
    pressTime, firstDown = 0, false --if it reaches here that means the double tap was successful or the key was incorrect, thus reset timer and flag
    return false --keeps the event propogating
end):start() --start our watcher

Any ideas what I am doing wrong?

[dasmurphy]

I also did wrote me a function for using fn to double tap to execute a function... May be this function helps you a little bit more. I check the flags and the key code. So you may need to adjust it a little bit.

Oh and for your code a tip: add a local to all functions so the functions are not available in the global scope but only in the local file.

local localTime = 0
local fnCounter = 0

local function keyDownHandler(event)
	local flags = event:getFlags()
	local characters = event:getCharacters(true)
	local keyCode = event:getKeyCode()

	-- Check for pressing FN two times to disable/enable Audioinput
	if flags['fn'] and not flags['cmd'] and not flags['ctrl'] and not flags['alt'] and keyCode == 63 then
		if (hs.timer.localTime() - localTime) >= 2 then
			fnCounter = 0
		end
		if fnCounter == 0 then
			localTime = hs.timer.localTime()
		end
		fnCounter = fnCounter + 1
		-- print('down',fnCounter)
		-- print(keyCode)
	end
	if not flags['fn'] and not flags['cmd'] and not flags['ctrl'] and not flags['alt'] and keyCode == 63 then
		-- print('up')
		fnCounter = fnCounter + 1
		if (hs.timer.localTime() - localTime) < 2 then
			-- pess two times fn and then change audioinput
			if fnCounter == 4 then
				fnCounter = 0
				-- insert here function call
				print('double fn pressed')
			end
		else
			fnCounter = 0
		end
		-- print(keyCode)
	end
end

keyDownEventListener = hs.eventtap.new({
		hs.eventtap.event.types.flagsChanged,
		hs.eventtap.event.types.keyDown
	}, keyDownHandler)
keyDownEventListener:start()

[MuhammedZakir]

That won't work for modifier keys. See #1025 (comment).

The eventtap object must be saved in a global variable (or a variable that is referenced by a global variable) to prevent GC from collecting it.

DoubleTapControl = eventtap.new({ event.keyDown }, function(event)
  ...
end):start()