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I am working on a react native app, where I am using FlatList for some purpose. I have a list of items displayed through the FlatList. That FlatList returns a component that I have made the finally displays the items.

const [allAmen , setAllAmen] = useState({});
let arr = [];
const test = (uName) => {
         setAllAmen({...allAmen , "name" : uName })
}
arr.push(allAmen);
console.log(arr);

<FlatList 
    data={amens}
    keyExtractor={(amen) => amen.id}
    renderItem={({item}) => {
        <TouchableOpacity
          onPress={() => {
             test(item.name)
          }}
        >
               <Text>{item.name}</Text>
        </TouchableOpacity>
    }}
/>

When I run this and press on one of the items of the list, it set the object in allAmen and pushes in arr. But if I press another item, it makes a new array and gives the result. S0 for every item of the flatlist a new state object and the array is created and the result is pushed in for a different array for each item. So if I have the following :

Flatlist ->

Candy Bar White Chocolate Bar Red Velvet

and I press on first I get -> [{"name": Candy Bar}] but then if I press on White Chocolate Bar it gives, [{"name" : White Chocolate Bar }] and same for Red Velvet.

What I want is if I press first i get -> [{"name" : Candy Bar}] then if I press second and after that third-> [{"name" : Candy Bar} , {"name" : White Chocolate Bar}, { "name" : Red Velvet}].

But it is running individually for every list. Can someone help me on how to do this? I am fairly new to react native and javascript and running it to a lot of doubts. Tried to find it on StackOverflow and internet but could not get anything relevant.

rohan
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1 Answers1

2
const newValue = {"name" : uName};
setAllAmen(prevArray => [...prevArray, newValue])

See more explanations. https://stackoverflow.com/a/58556049/905494 https://stackoverflow.com/a/54677026/905494

tksilicon
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  • This worked like a charm. Thanks for the links as well. The explanation made it very easy to understand what was happening. Cheers. – rohan Apr 17 '20 at 09:52