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Last active March 15, 2022 10:33
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Because sometimes we don't understand what's going on with DOM events (even more on mobiles), here's an HTML page to test and understand things 🦄
<!doctype html>
<html>
<head>
<title>Event testing.</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/normalize/8.0.1/normalize.min.css" integrity="sha512-NhSC1YmyruXifcj/KFRWoC561YpHpc5Jtzgvbuzx5VozKpWvQ+4nXhPdFgmx8xqexRcpAglTj9sIBWINXa8x5w==" crossorigin="anonymous" />
<script src="https://code.jquery.com/jquery-3.6.0.slim.min.js" integrity="sha256-u7e5khyithlIdTpu22PHhENmPcRdFiHRjhAuHcs05RI=" crossorigin="anonymous"></script>
<style>
* {
box-sizing: border-box;
}
html, body {
height: 100%;
}
body {
padding: 1em;
}
</style>
</head>
<body>
<input id="input" type="text" autofocus>
<script>
// https://stackoverflow.com/a/11616993/4112863
function safeStringify (obj, indent = 2)
{
let cache = []
const retVal = JSON.stringify(
obj,
(key, value) =>
typeof value === "object" && value !== null
? cache.includes(value)
? undefined // Duplicate reference found, discard key
: cache.push(value) && value // Store value in our collection
: value,
indent
);
cache = null
return retVal
}
// https://stackoverflow.com/a/7467863/4112863
function nl2br (str)
{
return (str + '').replace(
/([^>\r\n]?)(\r\n|\n\r|\r|\n)/g,
'$1<br>$2'
)
}
// https://stackoverflow.com/a/10474157/4112863
function space2nbsp (str)
{
return str.replace(/ /g, '\u00a0')
}
/**
* @param {String, Object} message
* @returns {void}
*/
function debug (message)
{
if (typeof message != 'string') {
message = space2nbsp(
nl2br(
safeStringify(message)
)
)
}
$('#debugConsole').append(`${message}<br>`)
.scrollTop($('#debugConsole')[0].scrollHeight)
}
/**
* @param {Object} handlers
* @param {Array} bypass
* @returns {void}
*/
function initialize (handlers = {}, bypass = [])
{
$('<div>').attr('id', 'debugConsole')
.css({
width: '100%',
height: '50%',
backgroundColor: 'crimson',
color: 'white',
fontWeight: 'bold',
position: 'absolute',
left: 0,
bottom: 0,
border: '1em solid crimson',
overflowY: 'auto',
fontFamily: 'monospace',
})
.appendTo($('body'))
const createEventHandler = name => {
return event => {
debug(name)
if (name in handlers) {
handlers[name](name, event)
}
}
}
Object.keys(window).forEach(key => {
if (/^on/.test(key)) {
const name = key.slice(2)
if (bypass.includes(name)) {
return
}
$(window).on(name, createEventHandler(name))
$('#debugConsole').on(name, event => {
event.stopImmediatePropagation()
})
}
});
['focusin', 'focusout', 'focus', 'blur'].forEach(name => {
$('#input').on(name, createEventHandler(name))
})
}
// Change these values according to your needs. These events are bypassed by
// default because they generate a LOT of output.
const bypass = [
'devicemotion',
'deviceorientation',
'deviceorientationabsolute',
'gotpointercapture',
'load',
'lostpointercapture',
'mousemove',
'mouseout',
'mouseover',
'mousewheel',
'pageshow',
'pointerrawupdate',
'wheel',
]
const handlers = {
keydown: (name, event) => {
debug(`>>> ${event.code}`)
debug(`>>> ${event.keyCode}`)
},
input: (name, event) => {
debug(`>>> ${$('#input').val()}`)
}
}
initialize(handlers, bypass)
</script>
</body>
</html>
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