Access passed data with StackNavigation outside render - reactjs

Question

I'm able to fetch a ListView and show details page onPress of any of the list item. I can show the details of the clicked item in the DetailsPage but only in the render(). How to access any of the value outside of the render? I want to use that value to fetch information from another API
Main Page:
import React, { Component } from 'react';
import {
AppRegistry, StyleSheet, ListView,
Text, TouchableHighlight, View
} from 'react-native';
import { StackNavigator } from 'react-navigation';
import DetailsPage from './src/DetailsPage';
class HomeScreen extends React.Component {
static navigationOptions = {
title: 'MyApp!',
};
constructor() {
super();
const ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
this.state = {
userDataSource: ds,
};
}
componentDidMount(){
this.fetchUsers();
}
fetchUsers(){
fetch('https://jsonplaceholder.typicode.com/users')
.then((response) => response.json())
.then((response) => {
this.setState({
userDataSource: this.state.userDataSource.cloneWithRows(response)
});
});
}
renderRow(user, sectionID, rowID, highlightRow){
const { navigate } = this.props.navigation;
return(
<TouchableHighlight onPress={() => navigate('DetailsPage', {users:user })}>
<View style={styles.row}>
<Text style={styles.rowText}> {user.name} </Text>
</View>
</TouchableHighlight>
)
}
render(){
return(
<ListView
dataSource = {this.state.userDataSource}
renderRow = {this.renderRow.bind(this)}
/>
)
}
}
const NavigationTest = StackNavigator({
Home: { screen: HomeScreen },
DetailsPage: { screen:DetailsPage },
});
AppRegistry.registerComponent('NavigationTest', () => NavigationTest);
Details Page:
import React, { Component } from 'react';
import { StyleSheet, ListView, Text, TouchableHighlight, View } from 'react-native';
export default class DetailsPage extends React.Component {
static navigationOptions = ({ navigation }) => ({
title: `${navigation.state.params.users.name}`,
});
// var userid = 2; --> This doesn't work as it returns Unexpected Token where var is mentioned.
constructor() {
super();
const ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
this.state = {
albumDataSource: ds,
};
}
componentDidMount(){
this.fetchAlbums();
}
fetchAlbums(){
var theUser = 2; //This is the value I want to receive from the clicked user.
// var newUser = this.props.navigation.state.users.id; -> this doesnt work.
fetch('https://jsonplaceholder.typicode.com/albums?userId='+newUser)
.then((response) => response.json())
.then((response) => {
this.setState({
albumDataSource: this.state.albumDataSource.cloneWithRows(response)
});
});
}
renderRow(album, sectionID, rowID, highlightRow){
return(
<TouchableHighlight>
<View style={styles.row}>
<Text style={styles.rowText}> {album.userId} - {album.title} </Text>
</View>
</TouchableHighlight>
)
}
render() {
const { params } = this.props.navigation.state;
return (
<View style={styles.container}>
<Text style={styles.textstyle}>Screen Chat with {params.users.name}</Text>
<Text style={styles.textstyle}>Username : {params.users.username}</Text>
<Text style={styles.textstyle}>Email : {params.users.email}</Text>
<Text style={styles.textstyle}>ID : {params.users.id}</Text>
<ListView
dataSource = {this.state.albumDataSource}
renderRow = {this.renderRow.bind(this)}
/>
</View>
);
}
}
So I want to use the users.id to fetch more data on the DetailsPage and display that data. How do I do that. Please help. Many thanks.

Answer 1

Here what i have found , this look wrong to me,
var newUser = this.props.navigation.state.users.id;
Use this may be it can help you
console.log(this.props.naviagtion.state.params) **Check if are getting those value then use below one **
var newUser = this.props.navigation.state.params.users.id;