I wanted to use querySelector()
but I find that Svelte has another way to do this.
by using bind:this
the problem is that sometimes it works, but the most of time it will never work
by outputting undefined
here is a simple example:
<script> let thisDiv; console.log(thisDiv) // ❌"undefined" ✅"<div>"</script><div bind:this={thisDiv}>hello world</div>
the real bug
but the real problem is here
because I don't need to
console.log
for nowthe things I wrote before are only for making you understand the bug
so I can start putting more information.
because I have a function that uses that variable
and call the function when the event "on:animationend
" starts.
like this:
<div bind:this={thisDiv} on:animationend={doStuff()}></div>
the problem is that animationend
still console.log the thisDiv
undefined
maybe is a problem of speed?
yes, ok...
but the animation in CSS only is 50ms long. and also tried with 0.5s
and CSS doesn't block the javascript, so js will continue to work when CSS is doing his animations (from what I know)
and 0.5s I think is a lot for doing a simple bind:this
(querySelector)
how is it even possible? half second for getting a normal querySelector and still nothing.
source code
here the REPL online svelte source code example:
https://svelte.dev/repl/b49d019ce7f8426b80295158b091520f?version=3.50.1
make sure to uncomment the line 9 in child.svelte
...or see this directly
App.svelte
<script> import Child from "./Child.svelte" function generateExample() { let output = []; for(let i=0; i<=100; i++) { output = [ ...output, `text ${i}` ] } return output; } let array = generateExample()</script>{#each array as item, index}<Child {index}> {item}</Child>{/each}
Child.svelte
<script> export let index; const DELAY = 50; let thisDiv; // UNCOMMENT THE NEXT LINE function doStuff() { // thisDiv.scrollIntoView(); }</script><div style="--delay:{index * DELAY}ms;" bind:this={thisDiv} on:animationend={doStuff()}><slot></slot></div><style> div { animation: show var(--delay); } @keyframes show { from { translate: 100vw; } to { translate: 0; } }</style>