How do I prevent a user clicking through an overlay? - react-native

I have an overlay positioned absolute, it has backgroundColor and it covers the whole screen. It's overlaying several button components which I can still click on through the overlay.
How do I prevent this behavior? I want to swallow all click events landing on the overlay first.
Code:
// Overlay
export default class Overlay extends Component {
render() {
return (
<View style={styles.wrapper} />
);
}
}
const styles = StyleSheet.create({
wrapper: {
position: "absolute",
top: 0,
left: 0,
bottom: 0,
right: 0,
backgroundColor: "black",
opacity: 0.7
}
});
// Container
export default class Container extends Component {
render() {
return (
<View>
<Overlay />
<Button onPress={() => this.doSomething()}>
<Text>Hello</Text>
</Button>
</View>
);
}
}

Write the absolute position component after other components to render it over the other components.
export default class Container extends Component {
render() {
return (
<View>
<Button onPress={() => this.doSomething()} title="Hello" />
<Overlay /> // provide appropriate height and width to the overlay styles if needed...
</View>
);
}
}

Solution 1- You can try to use Modal component from react-native
Solution 2- Wrap TouchableWithoutFeedback having blank onPress around your overlay. Don't forget to give full height and width to TouchableWithoutFeedback
something like
<TouchableWithoutFeedback>
<Overlay/>
<TouchableWithoutFeedback/>

Related

Position absolute not working inside ScrolView in React native

I was trying to position a button on the bottom right of the screen like the picture below:
So, basically I had a Scrollview with the button inside like so:
import React, { Component } from 'react'
import { ScrollView, Text, KeyboardAvoidingView,View,TouchableOpacity } from 'react-native'
import { connect } from 'react-redux'
import { Header } from 'react-navigation';
import CreditCardList from '../Components/credit-cards/CreditCardList';
import Icon from 'react-native-vector-icons/Ionicons';
import Button from '../Components/common/Button';
// Styles
import styles from './Styles/CreditCardScreenStyle'
import CreditCardScreenStyle from './Styles/CreditCardScreenStyle';
class CreditCardScreen extends Component {
render () {
return (
<ScrollView style={styles.container}>
<CreditCardList />
<TouchableOpacity style={CreditCardScreenStyle.buttonStyle}>
<Icon name="md-add" size={30} color="#01a699" />
</TouchableOpacity>
</ScrollView>
)
}
}
My styles:
import { StyleSheet } from 'react-native'
import { ApplicationStyles } from '../../Themes/'
export default StyleSheet.create({
...ApplicationStyles.screen,
container:{
marginTop: 50,
flex: 1,
flexDirection: 'column'
},
buttonStyle:{
width: 60,
height: 60,
borderRadius: 30,
alignSelf: 'flex-end',
// backgroundColor: '#ee6e73',
position: 'absolute',
bottom: 0,
// right: 10,
}
})
The problem is that the absolute positioning does not work at all when the button is inside the ScrollView. But...If I change the code to look like this:
import CreditCardScreenStyle from './Styles/CreditCardScreenStyle';
class CreditCardScreen extends Component {
render () {
return (
<View style={styles.container}>
<ScrollView >
<CreditCardList />
</ScrollView>
<TouchableOpacity style={CreditCardScreenStyle.buttonStyle}>
<Icon name="md-add" size={30} color="#01a699" />
</TouchableOpacity>
</View>
)
}
}
Then it works !! Whaat? Why? How? I don't understand why this is happening and I would appreciate any information about it.
This might be inconvenient but is just how RN works.
Basically anything that's inside the ScrollView (in the DOM/tree) will scroll with it. Why? Because <ScrollView> is actually a wrapper over a <View> that implements touch gestures.
When you're using position: absolute on an element inside the ScrollView, it gets absolute positioning relative to its first relative parent (just like on the web). Since we're talking RN, its first relative parent is always its first parent (default positioning is relative in RN). First parent, which in this case is the View that's wrapped inside the ScrollView.
So, the only way of having it "fixed" is taking it outside (in the tree) of the ScrollView, as this is what's actually done in real projects and what I've always done.
Cheers.
i suggest to use "react-native-modal".
you can not use position: 'absolute' to make elements full size in ScrollView
but you can do it by
putting that element in modal wrapper.
below are two examples. first one doesnt work but the second one works perfectly.
first way (doesnt work):
const app = () => {
const [position, setPosition] = useState('relative')
return(
<ScrollView>
<Element style={{position: position}}/>
<Button
title="make element fixed"
onPress={()=> setPosition('absolute')}
/>
</ScrollView>
)
}
second way (works perfectly):
const app = () => {
const [isModalVisible, setIsModalVisible] = useState(false)
return(
<ScrollView>
<Modal isModalVisible={isModalVisible}>
<Element style={{width: '100%', height: '100%'}}/>
</Modal>
<Button
title="make element fixed"
onPress={()=> setIsModalVisible(true)}
/>
</ScrollView>
)
}
for me this worked:
before:
<View>
<VideoSort FromHome={true} />
<StatisticShow style={{position:'absulote'}}/>
</View>
after:
<View>
<ScrollView>
<VideoSort FromHome={false} />
</ScrollView>
<View style={{position:'relative'}}>
<StatisticShow style={{position:'absulote'}}/>
</View>
</View>

Create a reusable React Native Modal Component

I'm going back to basics with React Native, as I feel overwhelmed. I have been looking for an implementation of a reusable modal component. I'm looking for examples of a reusable Modal component in RN? Thanks in advance
You can find many examples of this on StackOverflow. Still, if you need example I can help you with one example. You have mentioned modal component in your question, right?
Your component will look like this with props. let the name be ModalComponent for this file.
render() {
const { isVisible, message, textValue } = this.props;
return (
<Modal
animationType="slide"
transparent={false}
isVisible={isVisible}
backdropColor={"white"}
style={{ margin: 0 }}
onModalHide={() => {}}>
<View>
<Text>textValue</Text>
<Text>message</Text>
</View>
</Modal>
);
}
so now in your js file you need to import this modalComponent and after that, you need to write as
<ModalComponent
isVisible={true}
textValue={'hi there'}
message={'trying to make a basic component modal'}/>
Hope this will help for you
EDIT:
Create seperate components that you want to render inside modal. for Ex: component1.js, component2.js, component3.js with props
component1.js:
render(){
const { textVal, message } = this.props
return (
<View>
<Text>{textVal}</Text>
<Text>{message}</Text>
</View>
)
}
now in ModalComponent
render() {
const { first, second, third, isVisible, component1Text, component1Message } = this.props;
<Modal
animationType="slide"
transparent={false}
isVisible={isVisible}
backdropColor={"white"}
style={{ margin: 0 }}
onModalHide={() => {}}>
<View>
{first && <component1
textValue= component1Text
message= component1Message />}
{second && <Component2 />}
{third && <Component2 />}
</View>
</Modal>
In this way, you can achieve it within the single modal.
You will make a component like this giving the parent component all the liberty to change it through props.
render() {
const { isVisible, message, textValue, animationType, backDropColor, style, onModalHide, children } = this.props;
return (
<Modal
animationType= {animationType || 'slide'}
transparent={transparent || false}
isVisible={isVisible || false}
backdropColor={backdropColor || "white"}
style={[modalStyle, style]}
onModalHide={onModalHide}>
{children}
</Modal>
);
}
Then in your parent component, you need to import this component like this:
import ModalComponent from '../ModalComponent'; //path to your component
<ModalComponent isVisible={true}>
<View>
//any view you want to be rendered in the modal
</View>
</ModalComponent>
I had a lot of troubles using react-native modal, sometimes i started the app and could not close it even when i set the isVisible prop to false, it is even worst on IOs, i did a research and these packages are not being maintained properly.
You will save a lot of time by using a top-level navigator like is recommended in the modal docs: https://facebook.github.io/react-native/docs/modal.
I tried https://github.com/react-native-community/react-native-modal but had the same problems because its an extension of the original react-native modal.
I suggest you to use the react-navigation modal as described here: https://reactnavigation.org/docs/en/modal.html#docsNav
You can refer the following code to write Modal component once and use multiple times.
Write once:
import React, { Component } from 'react';
import { View, Text, Button, Modal, ScrollView, } from 'react-native';
export class MyOwnModal extends Component {
constructor(props) {
super(props);
this.state = {
}
render() {
return(
<Modal
key={this.props.modalKey}
transparent={this.props.istransparent !== undefined ? true : false}
visible={this.props.visible}
onRequestClose={this.props.onRequestClose}>
<View style={{
//your styles for modal here. Example:
marginHorizontal: width(10), marginVertical: '30%',
height: '40%', borderColor: 'rgba(0,0,0,0.38)', padding: 5,
alignItems: 'center',
backgroundColor: '#fff', elevation: 5, shadowRadius: 20, shadowOffset: { width: 3, height: 3 }
}}>
<ScrollView contentContainerStyle={{ flex: 1 }}>
{this.props.children}
</ScrollView>
</View>
</Modal>
);
}
}
Now,
You can call your Modal like following example: (By doing this, you avoid re-writing the Modal and its outer styles everytime!)
Example
<MyOwnModal modalKey={"01"} visible={true} onRequestClose={() =>
this.anyFunction()} istransparent = {true}>
<View>
// create your own view here!
</View>
</MyOwnModal>
Note: If you are in using different files don't forget to import , and also you can pass the styles as props.
(You can create/customise props too based on your requirement)
Hope this saves your time.
Happy coding!
I am a contributor of react-native-use-modal.
This is an example of creating a reusable modal in a general way and using react-native-use-modal: https://github.com/zeallat/creating-reusable-react-native-alert-modal-examples
With react-native-use-modal, you can make reusable modal more easily.
This is a comparison article with the general method: https://zeallat94.medium.com/creating-a-reusable-reactnative-alert-modal-db5cbe7e5c2b

React Native Modal transparent with backgroundColor black opacity 0.5 become darker between scene

RN 0.57,
React router flux 4
I have loader component to display loading message in modal on every scene.
I set the modal transparent and for modal content I set the backgroundColor: 'rgba(0, 0, 0, 0.5)'
This is the component code:
<Modal
transparent
visible={this.props.visible}
onRequestClose={() => {
console.log('modal closed')
}}
>
<View style={styles.modalBackground}>
.....
</View>
</Modal>
This is the stylesheet:
modalBackground: {
flex: 1,
alignItems: 'center',
flexDirection: 'column',
justifyContent: 'space-around',
backgroundColor: 'rgba(0, 0, 0, 0.5)'
},
This is where loader component to display:
<View style={{flex:1}}>
<Loader
visible={this.props.global.isLoading}
animating={this.props.global.isLoading}
/>
......
</View>
I change the state dispatch(setIsloading(true)) before HTTP REQ and dispatch(setIsloading(false)) after it return JSON from server, then it change to new Scene.
The problem is first visible modal is at correct color and transparent, but on the next scene, the color become darker and darker, it's like the component display multiple times at the next scene and triple after that.
Any idea What cause this problem?
As these tasks are async you have to make sure that the modal is dismissed before you move to the next scene, in your case you are moving to next scene before this modal is dismissed and once you are on next scene all the async subscriptions are removed hence your modal is not dismissing.
What I do for loading modals is that I do it by refs
In my loading component
export default class Loader extends Component{
hide = () => {
this.setState=({visible:false})
}
show = () => {
this.setState=({visible:true})
}
render(){
return(
<Modal isVisible={this.state.visible}>
....
</Modal>
)
}
}
where you want to show Loader
import Loader from 'path/to/loader'
<Loader ref={r=>this.loader = r}/>
and in your methods when you want to show loader
this.loader.show()
and hide it by calling
this.loader.hide()

react-native scrollview does now respect flex?

I'm learning flex layout for react native. This is my code:
import React, { Component } from 'react';
import {
Text,
View,
ScrollView
} from 'react-native';
const style = {
container: {
flex:1,
flexDirection:'column',
flexWrap:'nowrap',
alignItems:'stretch',
},
title: {
flex:1,
backgroundColor:'blue',
},
terms: {
flex:8,
flexDirection:'column',
backgroundColor:'red',
},
termsText: {
padding:15,
flex:1,
},
check: {
flex:1,
backgroundColor:'yellow',
}
};
export default class Home extends Component {
constructor(props)
{
super(props);
}
render() {
return (
<View style={style.container}>
<Text style={style.title}>Terms and Conditions</Text>
<ScrollView style={style.terms}>
<Text style={style.termsText}>You must comply, or die...</Text>
</ScrollView>
<Text style={style.check}>Check mark here (tap to agree to terms)</Text>
</View>
);
}
}
And the result is this:
This is not what I expected. I was expecting the red area to take up 80% of the vertical height because style.terms.flex == 8. If I changed the contents of my render to this:
render() {
return (
<View style={style.container}>
<Text style={style.title}>Terms and Conditions</Text>
<Text style={style.terms}>You must comply, or die...</Text>
<Text style={style.check}>Check mark here (tap to agree to terms)</Text>
</View>
);
}
I am then able to get the red area to become 80% vertical height. Why does ScrollView not respect style.terms.flex?
"Keep in mind that ScrollViews must have a bounded height in order to work, since they contain unbounded-height children into a bounded container (via a scroll interaction)." From the react native docs. What you can do is use the Dimensions API of react native and give the ScrollView 80% of device height instead.
More on ScrollView
Dimensions
Use Dimensions Api for ScrollView
const { width, height } = Dimensions.get('window');
<ScrollView style={{ height: height * 0.8 }}>
<Text style={style.termsText}>You must comply, or die...</Text>
</ScrollView>
height * 0.8 get the 80 percentage of height with respect to the screen size

Want to change opacity with react native refs on click

Here is my code. I want to change the opacity of refs when i click on any TouchableOpacity component.Please guide me how i can change opacity or change colour in react native with refs.
When i click my redirect function calls so i wanna change the opacity of particular ref in redirect function, i am passing ref and routename is redirect function.
i
mport React, { Component } from 'react';
import {
View,
Text,
TouchableOpacity,
StyleSheet
} from 'react-native';
export default class Navigation extends Component {
redirect(routeName,ref)
{
console.log(this.refs[ref]]);
this.props.navigator.push({
ident: routeName
});
}
render() {
return (
<View style={style.navigation}>
<View style={[style.navBar,styles.greenBack]}>
<TouchableOpacity style={style.navPills} onPress={ this.redirect.bind(this,"AddItem","a")} ref="a">
<Text style={[style.navText,style.activeNav]}>HOME</Text></TouchableOpacity>
<TouchableOpacity style={style.navPills} onPress={ this.redirect.bind(this,"AddItem","b")} ref="b">
<Text style={style.navText}>ORDER</Text></TouchableOpacity>
<TouchableOpacity style={style.navPills} onPress={ this.redirect.bind(this,"ListItem","c")} ref="c">
<Text style={style.navText}>SHOP LIST</Text></TouchableOpacity>
<TouchableOpacity style={style.navPills} onPress={ this.redirect.bind(this,"ListItem","d")} ref="d">
<Text style={style.navText}>DUES</Text></TouchableOpacity>
</View>
<View style={style.titleBar}>
<Text style={style.titleBarText}>{this.props.title}</Text>
</View>
</View>
);
}
}
const style = StyleSheet.create({
navigation:{
top:0,
right:0,
left:0,
position:'absolute'
},
navBar:{
flexDirection:'row',
padding:10,
paddingTop:15,
paddingBottom:15,
},
navPills:{
flex:1,
alignItems:'center'
},
navText:{
flex:1,
textAlign:'center',
fontSize:16,
fontWeight:'bold',
color:'#ffffff',
opacity:0.7
},
titleBar:{
backgroundColor:'#ffffff',
flex:1,
padding:8,
alignItems:'center',
borderBottomWidth:1,
borderBottomColor:'#dddddd'
},
titleBarText:{
fontSize:18
},
activeNav:{
opacity:1
}
});
I am not exactly sure if the following is what u are searching:
If you want to change the opacity of the TouchableOpacity use the following
export default class Navigation extends Component {
state={
opacity: 0.1
}
handleOnPress = () => {
this.setState({
opacity: 0.5 //Anything u want
});
}
render(){
return(
<TouchableOpacity underlayColor={'rgba(0,0,0,this.state.opacity)'} onPress={this.handleOnPress}>
)
}
}
If you want to change the opacity of your text use the following
export default class Navigation extends Component {
state = {
opacity: 0.1
}
handleOnPress = () => {
this.setState({
opacity: 0.5 //Anything u want
});
}
render(){
return(
<TouchableOpacity onPress={this.handleOnPress}>
<Text style={[style.navText, {opacity: this.state.opacity}]}>DUES</Text>
</TouchableOpacity>
)
}
}
Using the Stylemethods in the render allows you to take variables from the state
Hope this is the answer you wanted. If One of both is the right let me know and i delete the other one.
Best Regards
Put your opacity value into state. Then make the button click change the value of that state. This will trigger a re-render and your view will update with the new opacity.
To expand on the answer from pomo...
With the styles as you currently have them, you can easily call setState within each of your onPress functions to change the opacity of the elements you need changed. You don't even need to pass a reference if you utilize a different key in the state for each item.
Then, in your styles you would use an array of styles to use the opacity value from the state.
style={[style.navPills, { opacity: this.state.opacityA }]}
I'm not a fan of inline styles at all. So, for my purposes in a recent project I set the style of an element using its 'ref' value, then triggered a state change merely to cause the render function to be called. This is what I believe you're asking for and this sample code should point you in the right direction, otherwise perhaps this will help someone else in the future.
toggleDisplay() {
if (this.refs.blah.style.display === "") { // currently visible
this.refs.blah.style.display = "none";
this.setState({showBlah = false});
} else { // currently not visible
this.refs.blah.style.display = "";
this.setState({showBlah: true});
}
}
render() {
// Some element defined with the ref value used above.
return (<div>
<div ref="blah">Now you see me...</div>
<button onClick="this.toggleDisplay">Toggle Me</button>
</div>);
}
Nothing in my render function changed by adding the toggle functionality, other than adding a button somewhere to call the function. As I already indicated, that state value is only used to trigger the render process.