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ViewsReact map function not assinging keys properly
for some reason, I get the "each child in a list should have unique key" error when returning the following code. I do not understand why this happens, as I specifically assign the key during mapping:
return (
<>
{sortfeedCards(feedCards)}
{loggedIn === true ? (feedCardsMod.map((card, index) => (
<>
<p>{index}</p>
<FeedCard key={index} cardData={card} loggedIn={loggedIn} />
</>
))) : ('')}
</>
)
And here's what the render looks like.. it seems to me that the index-variable does work:
Many Thanks in advance!
·
Santiago Gelvez
2 answers
Answer question0
The key needs to be on the outermost element, so on the Fragment, not the FeedCard:
feedCardsMod.map((card, index) => (
<React.Fragment key={index}>
<p>{index}</p>
<FeedCard cardData={card} loggedIn={loggedIn} />
<React.Fragment/>
))
(The shorthand syntax <></> for fragments doesn't allow keys, so i switched to using React.Fragment explicitly)
·
Santiago Gelvez
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0
Try this:
return (
<>
{sortfeedCards(feedCards)}
{loggedIn === true ? (feedCardsMod.map((card, index) => (
<div key={index}>
<p>{index}</p>
<FeedCard cardData={card} loggedIn={loggedIn} />
</div>
))) : ('')}
</>
)
Keys must be unique amongst the enclosing tags: https://reactjs.org/docs/lists-and-keys.html
·
Santiago Gelvez
Report
Answer question