How to tell IntelliJ about javascript event properties so it stops warning about undefined props?

Question

IntelliJ seems to constantly complain about "Unresolved variable" for JavaScript.

For example, in

document.getElementById('myId').onclick = async event => {
    if (event.target.classList.contains...

it will underline classList with a warning "Unresolved variable classList"

classList is a well defined property. But an EventTarget could in theory be other things. Is there a "right" way to code or annotate it such that IntelliJ doesn't complain?

JSDoc comment describing `event.target`'s type should help here. — Oksana, Nov 01 '19 at 14:50

score 2 · Accepted Answer · answered Nov 07 '19 at 16:39

2

The IDE has no idea what your target element is, and EventTarget interface doesn't have classList property. You need to explicitly tell the IDE the type of the HTMLElement which is your target. For example:

document.getElementById('myId').onclick = async event => {
  const target = /** Element */ event.target;
  if (target.classList.contains

answered Nov 07 '19 at 16:39

lena

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This should probably be `@type {HTMLElement}`, see https://stackoverflow.com/a/21489264/5069530 – Ingo Steinke Nov 09 '22 at 09:07

How to tell IntelliJ about javascript event properties so it stops warning about undefined props?

1 Answers1