Multiple drag and drop simultaneous in React Native - react-native

Question

Hello i'm creating a game in react native and i'm stuck because i wan't both players can drag and drop horizontaly an element in same time on the same phone.
I have two components like that:
export class Player1 extends Component{
constructor(props){
super(props);
this.state = {
pan : new Animated.ValueXY()
};
}
componentWillMount(){
this.panResponder = PanResponder.create({
onMoveShouldSetResponderCapture : () => true,
onMoveShouldSetPanResponderCapture : () => true,
onPanResponderGrant : (e, gestureState) => {
this.state.pan.setOffset({x: this.state.pan.x._value, y: this.state.pan.y._value});
this.state.pan.setValue({x: 0, y: 0});
},
onPanResponderMove : Animated.event([null,{
dx : this.state.pan.x,
}]),
onPanResponderRelease: (e, {vx, vy}) => {
}
});
}
render(){
return (
<View style={styles.mainContainer}>
{this.renderDraggable()}
</View>
);
}
renderDraggable(){
return (
<View style={styles.draggableContainer}>
<Animated.View
style={[this.state.pan.getLayout(), styles.triangle]}
{...this.panResponder.panHandlers} >
</Animated.View>
</View>
);
}
}
And in my screen i call my components like that:
export default function HomeScreen() {
return (
<View>
<Player1></Player1>
<Player2></Player2>
</View>
);
}
Thanks for your help

Answer 1

I found a solution, i used react-native-gesture-handle like in the directory doubleDraggable of the example: https://kmagiera.github.io/react-native-gesture-handler/docs/example.html
My Code:
import React, { Component } from 'react';
import { Animated, StyleSheet, View } from 'react-native';
import {
PanGestureHandler,
ScrollView,
State,
} from 'react-native-gesture-handler';
export class Players extends Component {
constructor(props) {
super(props);
this._translateX = new Animated.Value(0);
this._translateY = new Animated.Value(0);
this._lastOffset = { x: 0, y: 0 };
this._onGestureEvent = Animated.event(
[
{
nativeEvent: {
translationX: this._translateX,
},
},
],
);
}
_onHandlerStateChange = event => {
if (event.nativeEvent.oldState === State.ACTIVE) {
this._lastOffset.x += event.nativeEvent.translationX;
this._translateX.setOffset(this._lastOffset.x);
this._translateX.setValue(0);
this._translateY.setOffset(this._lastOffset.y);
this._translateY.setValue(0);
}
};
render() {
return (
<PanGestureHandler
{...this.props}
onGestureEvent={this._onGestureEvent}
onHandlerStateChange={this._onHandlerStateChange}>
<Animated.View
style={[
styles.box,
{
transform: [
{ translateX: this._translateX },
{ translateY: this._translateY },
],
},
this.props.boxStyle,
]}
/>
</PanGestureHandler>
);
}
}
export default class Example extends Component {
render() {
return (
<View style={styles.scrollView}>
<DraggableBox />
</View>
);
}
}
const styles = StyleSheet.create({
scrollView: {
flex: 1,
},
box: {
position: 'absolute',
width: 0,
height: 0,
backgroundColor: 'transparent',
borderStyle: 'solid',
borderLeftWidth: 25,
borderRightWidth: 25,
borderBottomWidth: 50,
borderLeftColor: 'transparent',
borderRightColor: 'transparent',
},
});
And Screen:
<View styles={styles.container}>
<Players boxStyle={styles.player1}></Players>
<Players boxStyle={styles.player2}></Players>
</View>

Answer 2

I have been searching for something similar endlessly for a few days but I couldn't find these demos that react-native-gesture-handler provides. Thanks a lot for posting this here #Lillian Pacaud. Here is the link for several of their demos including the draggable component: https://snack.expo.dev/#adamgrzybowski/react-native-gesture-handler-demo
If you need any simultaneous presses/gesture/drags/etc... your best bet is to use react-native-gesture-handler because the native implementation of all touch/gesture-based components in react native don't allow for simultaneous interactions with each especially for Android.
I made a functional component that does the same thing as the accepted answer. Just pass whatever you want to be draggable as a child under the component. It can handle simultaneous drags as well like the accepted answer on both iOS and Android.
Example of using the draggable component:
import React from 'react';
import { View } from 'react-native';
import { DraggableTest } from '../components/test';
export default function Screen() {
return (
<View style={{ flex: 1 }}>
<DraggableTest>
<View
style={{ width: 150, height: 150, backgroundColor: 'lime' }}
/>
</DraggableTest>
</View>
);
}
The draggable component:
import React, { useRef } from 'react';
import { Animated, StyleSheet } from 'react-native';
import { PanGestureHandler, State } from 'react-native-gesture-handler';
export function DraggableTest({ children }) {
const pan = useRef(new Animated.ValueXY()).current;
const lastOffset = useRef({ x: 0, y: 0 }).current;
const onGestureEvent = Animated.event(
[{ nativeEvent: { translationX: pan.x, translationY: pan.y } }],
{ useNativeDriver: false },
);
const onHandlerStateChange = event => {
if (event.nativeEvent.oldState == State.ACTIVE) {
lastOffset.x += event.nativeEvent.translationX;
lastOffset.y += event.nativeEvent.translationY;
pan.setOffset({ x: lastOffset.x, y: lastOffset.y });
pan.setValue({ x: 0, y: 0 });
}
};
return (
<PanGestureHandler
onGestureEvent={onGestureEvent}
onHandlerStateChange={onHandlerStateChange}>
<Animated.View style={[pan.getLayout(), styles.animatedView]}>
{children}
</Animated.View>
</PanGestureHandler>
);
}
const styles = StyleSheet.create({
animatedView: {
position: 'absolute',
},
});