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Onpress method does not work in React Native?

I am getting an error that I do not understand when using the useState and useSetState functions that I sent as prop to the component I created.
Here is the main component which the CalcButton placed:
export const Calculator = () => {
const [operationText, setOperationText] = React.useState('');
const [operationHistory, setOperationHistory] = React.useState([]);
return (
<SafeAreaView>
<CalcButton operationText={operationText} setOperationText={setOperationText} />
</SafeAreaView>
);
};
Calcbutton.tsx Component
export default function CalcButton(
operationText,
setOperationText,
) {
const handleClick = () => {
setOperationText('2')
};
return (
<View style={styles.container}>
<TouchableOpacity onPress={handleClick} style={styles.inner}>
<View style={styles.middleInner}>
<Text style={styles.label}>=</Text>
</View>
</TouchableOpacity>
</View>
);
}
[enter image description here][1]
When I click CalcButton it gives that error.
https://i.stack.imgur.com/FFfYl.png
Thanks for all helps!

In CalcButton component I added curly braces to my props and it works
export default function CalcButton(
{operationText,
setOperationText}
) {
const handleClick = () => {
setOperationText('2')
};
return (
<View style={styles.container}>
<TouchableOpacity onPress={handleClick} style={styles.inner}>
<View style={styles.middleInner}>
<Text style={styles.label}>=</Text>
</View>
</TouchableOpacity>
</View>
);
}

How to pass onPress to props.children?

I'm trying to make a wrapper component in react-native that I can pass down all its props to the children it wraps around. What I really want is to pass down all function props down to all its children. It looks something like this below. I want the onPress in Wrapper to be called when the TouchableOpacity is pressed.
I tried this below but it doesn't work
const Wrapper = ({children,...props})=>{
return <View {...props}>{children}</View>
}
const App = ()=>{
return (
<View style={{flex:1}}>
<Wrapper onPress={()=>{console.log(2)}}>
<TouchableOpacity/>
</Wrapper>
</View>
)
}

It looks like you're looking to map the children and apply the props to each one. That might look like this:
const Wrapper = ({children,...props})=>{
return (<>
{React.Children.map(children, child => (
React.cloneElement(child, {...props})
))}
</>);
}
(method of mapping the children borrowed from this answer)

const App = () => {
return (
<View style={{ flex: 1 }}>
<TouchableOpacity onPress={() => {
// do the action need here here
}}>
<Wrapper >
</Wrapper>
</TouchableOpacity>
</View>
)
}
I would advise you to use hooks function instead
If you try to reuse functions that are related
** useAdd.js **
export default () => {
const addFuction(a, b) => {
// do preprocessing here
return a + b
}
return [addFuction]
}
main componet
import useAdd from "/useAdd";
const App = () => {
const [addFuction] = useAdd()
return (
<View style={{ flex: 1 }}>
<TouchableOpacity onPress={() => {
addFuction(4,5)
}}>
...action component...
</TouchableOpacity>
</View>
)
}
console in useAdd hook.... to see visual changes use the react useState

RN - Map directly from state syntax

I'm trying to map an array from state - but confused re the correct syntax - can anyone please advise where i'm going wrong:
This is what I have at the mo:
newsStorys = () => {
return (
{this.state.newsFeed.map((a) => {
<View style={ModalStyles.newsArticle}>
<Text style={ModalStyles.newsDate}>{a.date}</Text>
<Text style={ModalStyles.newsTitle}>{a.title}</Text>
<Text style={ModalStyles.newsDesc}>
{a.story}
</Text>
</View>
}
}
);
};

I'm not sure if that is the whole code of your component, but I can see three things.
If newsFeed is not initialized when component first render (let's say it is undefined yet), then newsFeed.map()will throw an exception.
You are not returning anything from map call. you should write something like this:
newsStorys = () => {
if (!this.state.newsFeed) return null;
return this.state.newsFeed.map((a) => ({ // <--- note the parentheses here, you don't have it
<View style={ModalStyles.newsArticle}>
<Text style={ModalStyles.newsDate}>{a.date}</Text>
<Text style={ModalStyles.newsTitle}>{a.title}</Text>
<Text style={ModalStyles.newsDesc}>
{a.story}
</Text>
</View>
});
);
};
If you want to avoid the parentheses, then you need to explicitly return something, like this:
this.state.newsFeed.map((a) => {
return (
<View style={ModalStyles.newsArticle}>
<Text style={ModalStyles.newsDate}>{a.date}</Text>
<Text style={ModalStyles.newsTitle}>{a.title}</Text>
<Text style={ModalStyles.newsDesc}>
{a.story}
</Text>
</View>
);
});
It is possible that you need an extra view to wrap the list of views returned by map.
Also you need to provide a unique key to each view, so React can keep track on them.
<View style={ModalStyles.newsArticle} key={'nome unique value'}>
...
</View>
Finally I think it would be better using a FlatList instead of map.
Cheers!

Had a play and a good dig around the web and found the syntax answer: (Thanks to Bruno for the Key and pointers).
newsStorys = () => {
return this.state.newsFeed.map((value, index) => {
return (
<View style={ModalStyles.newsArticle} key={index}>
<Text style={ModalStyles.newsDate}>{value.date}</Text>
<Text style={ModalStyles.newsTitle}>{value.title}</Text>
<Text style={ModalStyles.newsDesc}>{value.story}</Text>
</View>
);
});
};

Try this
newsStorys = () => (
this.state.newsFeed.map(({ date, story, title }, index) =>
<View key={`news-${index}`} style={ModalStyles.newsArticle}>
<Text style={ModalStyles.newsDate}>{date}</Text>
<Text style={ModalStyles.newsTitle}>{title}</Text>
<Text style={ModalStyles.newsDesc}>{story}</Text>
</View>
));

React Native Swipeable close after onPress not working

So I've seen many posting the same problem, but for some I don't seem to be able to adapt the posted solutions to my case.. I hope someone can tell me exactly what changes I need to do in order to get this working, since I don't know how to implement the suggested solutions!
I am using React Native Swipeable
Example of someone having the same issue
I have a file in which I built the Swipeable Component and an other class which calls the component. I've set a timeout close function on the onSwipeableOpen as a temporary solution. But ideally it should close immediately upon pressing "delete". The "..." stands for other code which I deleted since it's not important for this case.
AgendaCard.js
...
const RightActions = ({ onPress }) => {
return (
<View style={styles.rightAction}>
<TouchableWithoutFeedback onPress={onPress}>
<View style={{ flexDirection: "row", alignSelf: "flex-end" }}>
<Text style={styles.actionText}>Löschen</Text>
<View style={{ margin: 5 }} />
<MaterialIcons name="delete" size={30} color="white" />
</View>
</TouchableWithoutFeedback>
</View>
);
};
...
export class AgendaCardEntry extends React.Component {
updateRef = (ref) => {
this._swipeableRow = ref;
};
close = () => {
setTimeout(() => {
this._swipeableRow.close();
}, 2000);
};
render() {
return (
<Swipeable
ref={this.updateRef}
renderRightActions={() => (
<RightActions onPress={this.props.onRightPress} />
)}
onSwipeableOpen={this.close}
overshootRight={false}
>
<TouchableWithoutFeedback onPress={this.props.onPress}>
<View style={styles.entryContainer}>
<Text style={styles.entryTitle}>{this.props.item.info}</Text>
<Text style={styles.entryTime}>
eingetragen um {this.props.item.time} Uhr
</Text>
</View>
</TouchableWithoutFeedback>
</Swipeable>
);
}
}
Agenda.js
...
renderItem(item) {
...
<AgendaCardAppointment
item={item}
onRightPress={() => firebaseDeleteItem(item)}
/>
...
}

I'm having the same issue and have been for days. I was able to hack through it, but it left me with an animation I don't like, but this is what I did anyways.
export class AgendaCardEntry extends React.Component {
let swipeableRef = null; // NEW CODE
updateRef = (ref) => {
this._swipeableRow = ref;
};
close = () => {
setTimeout(() => {
this._swipeableRow.close();
}, 2000);
};
onRightPress = (ref, item) => { // NEW CODE
ref.close()
// Delete item logic
}
render() {
return (
<Swipeable
ref={(swipe) => swipeableRef = swipe} // NEW CODE
renderRightActions={() => (
<RightActions onPress={() => this.onRightPress(swipeableRef)} /> // NEW CODE
)}
onSwipeableOpen={this.close}
overshootRight={false}
>
<TouchableWithoutFeedback onPress={this.props.onPress}>
<View style={styles.entryContainer}>
<Text style={styles.entryTitle}>{this.props.item.info}</Text>
<Text style={styles.entryTime}>
eingetragen um {this.props.item.time} Uhr
</Text>
</View>
</TouchableWithoutFeedback>
</Swipeable>
);
}
}

React-Native: Cannot access state values or any methods declared from renderRow

I have a listview, whenever user clicks on an item, i want to do something with onPress (touchable highlight).
I tried defining function then calling them in onPress but they didnt work.
first i defined a function like this :
constructor(props) {
super(props);
this.state = {
dataSource: new ListView.DataSource({
rowHasChanged: (row1, row2) => row1 !== row2,
}),
loaded: false,
};
this._dosome = this._dosome.bind(this);
}
_dosome(dd){
console.log(dd);
}
Then :
render(){
if (!this.state.loaded) {
return this.renderLoadingView();
}
return (
<View style={{
flex: 1
}}>
<ListView
dataSource={this.state.dataSource}
renderRow={this.renderRow}
style={styles.listView}
/>
</View>
);
}
renderRow(data) {
var header = (
<View>
<View style={styles.rowContainer}>
<View style={styles.textContainer}>
<Text style={styles.title}>{data.nid}</Text>
<Text style={styles.description} numberOfLines={0}>{data.title}</Text>
</View>
</View>
<View style={styles.separator}></View>
</View>
);
///////////
var cid = [];
var content = [];
for(let x=0; x < Object.keys(data.course).length; x++){
cid[x] = data.course[x].course_id;
content.push(
<TouchableHighlight
underlayColor='#e3e0d7'
key={x}
onPress={ this._dosome } //// **** PROBLEM HERE ****
style={styles.child}
>
<Text style={styles.child}>
{data.course[x].title}
</Text>
</TouchableHighlight>
);
}
console.log(cid);
var clist = (
<View style={styles.rowContainer}>
{content}
</View>
);
////////////
return (
<Accordion
header={header}
content={clist}
easing="easeOutCubic"
/>
);
}
renderLoadingView() {
return (
<View style={styles.loading}>
<Text style={styles.loading}>
Loading Courses, please wait...
</Text>
</View>
);
}
}
But it didnt worked, error :
TypeError: Cannot read property '_dosome' of null(…)
I tried calling it onPress like this :
onPress={ this._dosome.bind(this) }
didn't help
onPress={ ()=> {this._dosome.bind(this)}}
didn't help
onPress={ console.log(this.state.loaded)}
even i cannot even access props defined in constructor. it don't know what is "this" !
I tried to define the function other way like this :
var _dosome = (dd) => {
console.log(dd);
};
I tried defining the _dosome before render, after render, inside render, inside renderRow, and after renderRow. all same results.
I did check lots of tutorials, lots of sample apps on rnplay, lots of threads in stackoverflow, lots of examples, but none of them worked for me.
any solutions/ideas?
Any help is highly appreciated. i'm struggling with this issue for 2 days now.
Thanks in Advance!

How to solve your problem
Change
<ListView
dataSource={this.state.dataSource}
renderRow={this.renderRow}
style={styles.listView}
/>
To
<ListView
dataSource={this.state.dataSource}
renderRow={data => this.renderRow(data)}
style={styles.listView}
/>
Or
<ListView
dataSource={this.state.dataSource}
renderRow={this.renderRow.bind(this)}
style={styles.listView}
/>
Why?
As you already know(since you are trying to solve the problem by using arrow function and bind), to call renderRow, the caller should be in the same context as the component itself.
But this connection is lost in renderRow={this.renderRow}, which created a new function(new context).