Passing Date object is prop in react - reactjs

I'm trying to pass a date object as a prop in react native, and access its methods to render data.
The prop is passed as following:
<Task
text={item["text"]}
date={item["date"]}
time={item["time"]}
reminder={item["reminder"]}
completed={item["completed"]}
/>
It is accessed as:
<View>
<View
style={[
styles.item,
completed
? { backgroundColor: "#98CBB4" }
: { backgroundColor: "#CCC9DC" },
]}
>
<View style={styles.ciricleTitle}>
<View style={styles.circular}></View>
<Text style={styles.itemText}>{text}</Text>
</View>
<Text style={styles.itemText}>{console.log(date.date)}</Text>
{/* <Text style={styles.itemText}>{date.getDay()}</Text> */}
</View>
{completed && <View style={styles.line} />}
</View>
i tried expanding the prop with {...item['date']} but it is not working

We have to convert string to date object, You can use new Date(date).getDay()

Let's clarify your doubt first.
sending date which is a string as a prop
sending date which is an object as a prop
So, you have made the mistake here. You have sent the date string rather than as the date object and trying to access the properties.
<div>
{
itemList.map(({ text, date, time, reminder, completed }) => (
<Task {...{ text, date, time, reminder, completed }} />
))
}
</div>
The date you are passing here undoubtedly is a string(which is item.date)
One way to acheive what you want is, send it as a date object..
<Task
{...{
text,
time,
reminder,
completed,
date: new Date(date)
}}
/>
So that,
<Text style={styles.itemText}>{date.getDay()}</Text>
would become valid.

Related

React Native Typescript : how to resolve an error of type of parameter for a variable

I'm doing a project in react native (typescript) and here is my issue : I have this error Argument of type 'GestureResponderEvent' is not assignable to parameter of type 'SetStateAction<string>'.ts(2345) with this part of my code, at the i of setSelected :
<View style={{}}>
<Text style={styles.texteti}>Heading, paragraphe, lien</Text>
{state.map((i) => (
<TouchableOpacity onPress={(i) => setSelected(i)}>
<Text>{i} Here</Text>
</TouchableOpacity>
))}
{selected == "v1Visible" && (
<View>
<Text>View 1</Text>
</View>
)}
{selected == "v2Visible" && (
<View>
<Text>View 2</Text>
</View>
)}
{selected == "v3Visible" && (
<View>
<Text>View 3</Text>
</View>
)}
{selected == "v4Visible" && (
<View>
<Text>View 4</Text>
</View>
)}
</View>
Anyone has an idea of how to resolve this
You are reusing the variable with name i in the callback function passed to onPress of the TouchableOpacity. You are using the same variable name in your map function of state. Since the setter setSelected is called in the local scope of the callback function of onPress, the event passed to this callback function will be used (it is stored in i of the local scope of the callback function).
The easiest fix would be to either rename the variable or not declare it at all since you are not using it anyway.
{state.map((i) => (
<TouchableOpacity onPress={() => setSelected(i)}>
<Text>{i} Here</Text>
</TouchableOpacity>
))}
If you actually want to store the event of the onPress action (which seems to be unlikely judging from your current code), you need to either change the typing of your state or access whatever you want to access from the event.

Hide picked items in a FlatList

I'm using react-native FlatList to render out a punch on elements the data of which comes from an external API.
I want to prevent the user from picking the same item twice. So the way I'm going about this it hiding the item after they pick it.
If, let's say, I have a state picked like so
const [ picked, setPicked ] = useState(false);
changing it will of course hide all the elements.
<FlatList
{/*some other props*/}
data={allCards}
renderItem={(card: ListRenderItemInfo<CardsProps>) => (
<TouchableOpacity
style={[ styles.holder, { display: picked ? "none" : "flex" } ]}
onPress={() => handleChoice(parseInt(card.item.id))}
>
<Card
{/*some card props*/}
/>
</TouchableOpacity>
)}
/>
How can I go about changing the state for only one element inside the FlatList??
Is there a better approach you would recommend to do the same job?
try it like this, it will work,
<FlatList
{/*some other props*/}
data={allCards}
renderItem={(card: ListRenderItemInfo<CardsProps>) => picked ? (
<TouchableOpacity
style={[ styles.holder, ]}
onPress={() => handleChoice(parseInt(card.item.id))}
>
<Card
{/*some card props*/}
/>
</TouchableOpacity>
): undefined}
/>
The easiest way to do this is if you create an object with all the ids and while inserting it you can check it whether it's in that list or not
it'll cost u O(1) time to check.
<FlatList
{/*some other props*/}
data={allCards}
renderItem={(card: ListRenderItemInfo<CardsProps>) => picked ? (
<TouchableOpacity
style={[ styles.holder, ]}
onPress={() => handleChoice(parseInt(card.item.id))}
>
<Card
{/*some card props*/}
/>
</TouchableOpacity>
): undefined}
/>
const map=new Map();
const handleChoice=(id)=>{
if(Map.get(id)===undefined){
Map.set(id,true)
//add the element to ur list where u need it to
}
}

How to underline a specific word in a string for a React Native button

I'm using a Button component from react-native-elements and for the title prop I would like to underline one of the words, is this possible?
button.js:
<Button
buttonStyle={styles.buttonStyle}
titleStyle={styles.titleStyle}
containerStyle={styles.containerStyle}
title={title}
onPress={onPress}
disabled={disabled}
disabledStyle={[styles.disabledStyle]}
/>
I'm using it like this:
<Button
title={'First line \nSecond line'} // <- How to underline First & Second?
onPress={() => console.log('pressed button')}
/>
How do I underline the words First and Second?
I tried doing title={`${First} line \n${Second} line`} where First and Second is a <Text style={{textDecoration: 'underline}}>First</Text> but I'm getting [object, Object] since it's not an expression
<Button> implementation in React Native Elements indeed does support passing component as title property value - but in your code you try to pass those as text. That's what you might try instead:
const ButtonTitle = (
<>
<Text style={{textDecoration: 'underline'}}>First</Text>
<Text style={{textDecoration: 'underline'}}>Second</Text>
</>
)
<Button title={ButtonTitle} />
For situations like this, I generally will use React.ReactNode as the type for title instead of a string. This will be backwards-compatible, as strings are valid ReactNodes, but it also allows you to do this:
// style example
const style = Stylesheet.create({
underline: { textDecoration: 'underline' },
});
// Implementation in component
title={
<Text>
<Text style={style.underline}>
First line
</Text>
<Text style={style.underline}>
Second line
</Text>
</Text>
}
Reminder that the original will also still work as ReactNode is a type which includes string:
title={'First line \nSecond line'}

Implementing a counter in a React Native Flat List

Background
I'm building a screen for an app which displays a number of products brought from a firebase firestore collection. The way I display the products is via a FlatList, this is the code:
<FlatList
style={selected ? styles.visible : styles.hidden}
data={data}
renderItem={({ item }) => (
<View style={styles.container}>
<View style={styles.left}>
<Text style={styles.title}>{item.name}</Text>
<Text style={styles.description}>{item.description}</Text>
<Text style={styles.price}>${item.price}</Text>
<View style={styles.adder}>
<TouchableOpacity onPress={() => setCount(count - 1)}>
<Text style={styles.less}>-</Text>
</TouchableOpacity>
<Text style={styles.counter}>{count}</Text>
<TouchableOpacity onPress={() => setCount(count + 1)}>
<Text style={styles.more}>+</Text>
</TouchableOpacity>
</View>
</View>
<Image style={styles.right} source={{uri: item.image}}/>
</View>
)}
/>
Problem
As you can see, there's a counter in place for each item which the user can use to select how many units of the product they want to buy. The state is updated like this: const [count, setCount] = useState(0);
As you can see, this way of implementing the counter means that adding one unit of any product adds a unit of every product.
What I have tried
I've seen some people do this: setCount({counterA: 0, counterB: 0, etc.}) and update each counter, however as the number of products is always changing in the firebase document I can't hardcode the amount of counters I need.
Question
How can I edit my code so that it only affects the desired item?
The item in your renderItem function should be a separate component. In this separate component you will have a count that is scoped only to the component. So when the button is pressed on that component, only its count is incremented and not the others. The problem right now is you have one count that is on the parent component. After creating this new "counting" componenet, your FlatList will look something like:
<FlatList
style={selected ? styles.visible : styles.hidden}
data={data}
renderItem={({ item }) => (
<CountingComponent />
)}
/>

Changing Visibility of a button inside the component dynamically

I am using React-Navigation but I guess You don't really need to have a prior knowledge about it.
So I have a header Component which looks like this
const Header = (props) => {
return (
<View style={headerContainer}>
<View>
<Button onPress={() => props.navigation.navigate('Home')}
title="Go Back"/>
</View>
<Text style={header}> Knicx
<Text style={headerSecondary}> Crypto Ticker </Text>
</Text>
</View>
)
}
Now, In the above notice the button, Which I am currently showing on all the pages
<Button onPress={() => props.navigation.navigate('Home')}
title="Go Back"/>
But I don't want it to be there on some specific pages, like HomeScreen to say the least.
Now, One solution is to remove the <Header /> component in my homepage, Copy the above code snippet, past it in my HomeScreen and remove the Component ( sort of like hardcoding ) or two create two Header component, one with button and one without button
[Question:] But I was thinking if we could toggle the visibility of button dynamically or stack it on the top of <Header /> ? Can someone please tell me how can we do it? (No, We can set the opacity of the button to zero and change it whenever we need it)
[Update:] We can use redux to manage/pass the state but the problem is that in React-native we do not have display: none and I don't want to change use the opacity
Send showHomeButton: boolean as a prop to header
const Header = props => (
<View style={headerContainer}>
{this.props.showHomeButton && (
<View>
<Button onPress={() => props.navigation.navigate('Home')} title="Go Back" />
</View>
)}
<Text style={header}>
{' '}
Knicx
<Text style={headerSecondary}> Crypto Ticker </Text>
</Text>
</View>
);

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