TextField: typewriter effect

pie

Hi, I'm sharing my custom textField to have typewriter effect on TextFields.
Just add speed (in milliseconds) as third parameter to TextField.new().
Base code from GiderosCodingEasy by @ar2sawseen: If you notice something to do to improve it please tell me

function TextField:init(...) local arg = {...}   --typewriter effect local function typewriter(str, speed) local i = 0 local in_str = str local str_length = string.len(in_str) local typeSpeedTimer = Timer.new(speed, str_length)   local function getString() if i <= str_length then i = i+1 --1 is the number of characters to add each time local out_str = string.sub(in_str, 1, i) self._text:setText(out_str) self._text:setVisible(true) end end   typeSpeedTimer:addEventListener(Event.TIMER, getString) typeSpeedTimer:start() end   self._text = _TextField.new(...) self._text:setVisible(false) self:addChild(self._text) self._font = arg[1]   --if string and speed are specified if arg[2] and arg[3] then local str = arg[2] local typewritespeed = arg[3] typewriter(str, typewritespeed) end   self._offsetX = 0 self._offsetY = 0   local baseX, baseY = self._text:getBounds(stage) self._text:setPosition(-baseX, -baseY) end

usage:

local testtxt= TextField.new(nil, "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.", 10) stage:addChild(testtxt)

>-

EDIT - update fix.
However, there is a speed limit I didn't think of, since refresh rate can't go faster than some value (cpu? gpu?, ram speed?).
To avoid this, you can change the increment of characters in function getString() - keep in mind that timer should run accordingly:
Timer.new((str_lenght/number of characters per timer call), speed) )

MoKaLux

based on your work pie https://wiki.gideros.rocks/index.php/TypeWriter_@mokalux

pie

I completely forgot I did that

pie

I would say that using # to get the length of a string is usually much faster than using string:len() at least on my laptop and if today I didn't make a big mistake in maths.

test = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur." local astartTime = os.timer() local v = #test local aendTime = os.timer() - astartTime   local bstartTime = os.timer() local q = test:len() local bendTime = os.timer() - bstartTime   print("#", aendTime, ":len()", bendTime)

this is my output

# 1.9999970390927047e-07 :len() 6.999998731771484e-07 Uploading finished. # 1.9999970390927047e-07 :len() 8.999995770864189e-07 Uploading finished. # 1.9999970390927047e-07 :len() 8.000006346264854e-07 Uploading finished. # 2.0000000011677344e-07 :len() 5.999999999062311e-07 Uploading finished. # 5.999999999062311e-07 :len() 5.000000005139782e-07

EDIT: Before anyone decides to use # instead of utf8.len keep in mind that

there could be an issue if you use non ascii chars. You’d better use utf8.len and utf8.sub to deal with multi byte characters.

pie

And I don't know if someone might ever need it, but this is the same function that returns the string through a callback function. It might be used in conjunction with a standard TextField without the need to create a new Core object.

txt = "Lorem ipsum dolor sit amet, consectetur adipiscing elit"   --f is the output "typed" text, if e is present the text has been completely typed. local function typewriter_callback(f, e) --ie. myTextfield:setText(f) print(f) if e then --finished print(e) end end       local function typeWriterr(text, speed, char, callback) local i = 0 local in_str = text local str_length = in_str:len() local typeSpeedTimer = Timer.new(speed or 100, str_length) char = char or 1   local function getString() if i <= str_length then i += char -- number of characters to add each time local out_str = in_str:sub(1, i) if i == str_length then callback(out_str, "END") else callback(out_str) end end end typeSpeedTimer:addEventListener(Event.TIMER, getString) typeSpeedTimer:start() end     typeWriterr(txt,nil,nil,typewriter_callback)

hgy29

If I may say, there could be an issue if you use non ascii chars. You’d better use utf8.len and utf8.sub to deal with multi byte characters.