Moving to Next Screen in react native - reactjs

If i click on Lungs Banks i want to move to another screen How can i do this
<KeyboardAvoidingWrapper>
<WelcomeStyledContainer>
<StatusBar style="dark" />
<OrganHeading>
<OrganHeadingText>Donate Able Organ</OrganHeadingText>
</OrganHeading>
<View style={styles.container}>
<View style={styles.Box}>
<View style={styles.inerBox}>
<CardStyle>
<CardImage source={require('./../assets/organImage/lungs.png')} />
<CardText>Lungs Bank</CardText>
</CardStyle>
</View>
</View>

Below solution will work for you if you are using React-navigation.
UI Screen:
<CardText onPress={()=>navigation.navigate("YOUR SCREEN NAME HERE")}>Lungs Bank</CardText>
Card Text Component:
const CardText = ({onPress}) => {
return <Text onPress={onPress}>{props.children}</Text>;
}
Thanks!

You can use react-navigation
library to get started with navigation in react-native.

Related

Multiple sticky headers in a React native scrollview

I am trying to have multiple sticky headers in a React Native scrollview using stickyHeaderIndices prop but it only sticks the last header.
For example the following code with only stick This is the title 2 when I would expect to have the three titles on the top of the screen.
export default function App() {
return (
<ScrollView style={styles.container} stickyHeaderIndices={[0, 1, 2]}>
<Text style={styles.title}>
This is the title 0
</Text>
<Text style={styles.title}>
This is the title 1
</Text>
<Text style={styles.title}>
This is the title 2
</Text>
<AssetExample />
<AssetExample />
<AssetExample />
<AssetExample />
<AssetExample />
</ScrollView>
);
}
Here is a reproduction code: https://snack.expo.dev/#abumalick/scrollview-multiple-sticky-headers. You can check in android and iOS.
After seeing this implementation: https://github.com/deepseapenguin/react-native-sticky-header-flatlist#result
I understand that the purpose of sticky headers indices is to display only one header at a time. When the user scrolls to a new sticky header, it replaces the previous one. It is not intended to display multiple headers at a time.

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>
);

React Native: memory is not released when navigating away from FlatList view

I'm on "react-native": "0.53.3". When navigating to a view with a FlatList containing ~100 components and then navigating back, not all the memory is released, which means that after a few navigations my app is consuming too much memory and crashes. This is my flatlist component which renders comment.js
return (
<Container style={{ flex: 1}}>
<FlatList
data={comments}
keyExtractor={this._keyExtractor}
renderItem={this.renderComment}
removeClippedSubviews
/>
</Container>
);
comment.js looks pretty much like this:
return (
<View>
<TouchableHighlight onPress={this.toggleCollapse}>
{this.renderHeaderWithBorder(depth)}
</TouchableHighlight>
<Collapsible collapsed={this.state.collapsed} align="top">
<TouchableHighlight onPress={this.toggleCollapse}>
{this.renderBodyWithBorder(depth)}
</TouchableHighlight>
</Collapsible>
</View>
);
I've noticed that if i change comment.js to render a simple Text component the problem goes away (the app sits around 300mb with high usage)
I'm using "react-navigation": "1.1.1" and redux.
It seems to me that the memory for each new comment list isn't being released when the component is unmounted, is there anyway I can mitigate this?

React Native, I can't tap without closing keyboard

Here is my phone screen I tried ScrollView with keyboardShouldPersistTaps, but it didn't work. I have a ScrollView for Autocomplete suggestions, and when user can types there, they should also be able to select from suggestions. However, without closing keyboard, it is not possible in my case. Here is my work
<ScrollView
scrollEnabled={false}
keyboardShouldPersistTaps={true}>
<View style={{ maxHeight: 220 }}>
<ScrollView style={Style.suggestionContainer}
scrollEnabled={true} >
{this.state.showOptions.map(this.renderSuggestions)}
</ScrollView>
</View>
</ScrollView>
.
.
.
private renderSuggestions(option: MultiInputQuestionOption) {
return (
<TouchableOpacity onPress={this.addSelection.bind(this, option)} >
<Text style={Style.suggestions}>
{option[this.props.titleKey]}
</Text>
</TouchableOpacity >
)
}
Is there any possible solution?
You need to pass the key keyboardShouldPersistTaps=‘handled’ on scroll view which contains the TextInput:-
<ScrollView keyboardShouldPersistTaps=‘handled’>
...
<TextInput />
</ScrollView>
And if you are having issue inside of a modal then You need to pass key keyboardShouldPersistTaps=‘handled’ on All scrollview which are in component stack for the screen. In the ancestors/parent of the Modal also.
Like in my case:
const CountryModal=(props)=>{
return(
<Modal
visible={props.visible}
transparent={false}
{...props}
>
<ScrollView keyboardShouldPersistTaps=‘handled’>
…
</ScrollView>
/>
)
}
In Parent class:
In the parent class where ancestors of modal is there. You need to pass key keyboardShouldPersistTaps=‘handled’`.
class Parent extends Component{
render(){
return(
<ScrollView keyboardShouldPersistTaps=‘handled’> // pass ‘handled’ here also
…
<CountryModal /> // Its the same modal being used as a component in parent class.
</ScrollView>
)
}
Try adding
keyboardShouldPersistTaps={'always'}
to the second ScrollView as well.
Use the 'handled' value for keyboardShouldPersistTaps property because the true value is deprecated. use the keyboardShouldPersistTaps in two ScrollViews and handle your keyboard state in somewhere else by using Keyboard.dismiss() function.

react-native-elements: The last few items in the Transaction List cannot be viewed at bottom

I am using react-native-elements to speed up the development of my react-native app.
I am using react-native ScrollView in my List element to enable scroll functionality.
Unfortunately, it seems that the List element is overflowing at the bottom, hiding the last few list item elements from view
Any idea why this is the case?
EDIT: Here is the render function of the list component
render () {
const { transactions, handleEditTransaction, handleDeleteTransaction } = this.props
return (
<View>
<View>
<List>
<ScrollView>
{
transactions.map((item, i) => (
<TransactionListItem
key={i}
item={item}
/>
))
}
</ScrollView>
</List>
</View>
</View>
)
}
I had the same problem. To solve this, go to the root <View> and add style={{flex: 1}}.
This means to also add this to the parent component if necessary.
<View style={{flex:1}}>
<ScrollView>
//Content here
</ScrollView>
</View>
parent component (if required)...
<View style={{flex:1}}>
<ChildComponent />
</View>

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