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How to pass in the state of my app from App.js to MainStack.Screen?

So I have my App.js which then renders a NavigationContainer with MainStack.Screen(s). I use an api to fetch some data about movies and then process it to give me a list of movieItem Objects with details about that movie. I save this moviesList object in my App.js state and want to pass this to my HomeScreen so that it can render all the movies in the moviesList object.
Please help how I can correctly get the route.params.moviesList[0].title to show.
App.js:
import { StatusBar } from 'expo-status-bar';
import React from 'react';
import { StyleSheet, Text, View } from 'react-native';
import { NavigationContainer } from '#react-navigation/native';
import { createStackNavigator } from '#react-navigation/stack';
import { createBottomTabNavigator } from '#react-navigation/bottom-tabs';
import HomeScreen from './Screens/HomeScreen';
import ResultsScreen from './Screens/ResultsScreen';
import { fetchMovies } from './api';
const MainStack = createStackNavigator();
export default class App extends React.Component {
state = {
moviesList: null,
};
componentDidMount() {
this.getUsers();
}
getUsers = async () => {
const movies = await fetchMovies();
this.setState({ moviesList: movies });
console.log('===========');
console.log(this.state.moviesList);
};
render() {
return (
<NavigationContainer>
<MainStack.Navigator>
<MainStack.Screen
name="Home"
component={HomeScreen}
initialParams={this.state}
/>
<MainStack.Screen name="Results" component={ResultsScreen} />
</MainStack.Navigator>
</NavigationContainer>
);
}
}
HomeScreen.js:
import React from 'react';
import { StyleSheet, TextInput, Button, Text, View } from 'react-native';
import Row from '../Row';
export default function HomeScreen({ route, navigation }) {
console.log('ROUTE:');
console.log(route);
return (
<View style={styles.container}>
<Text style={styles.heading}>Movie Browser</Text>
<Text style={styles.heading}>{route.params.moviesList[0].title}</Text>
<TextInput style={styles.textInput} placeholder="Sreach" />
<Row props />
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
alignItems: 'center',
},
heading: {
fontSize: 42,
padding: 20,
},
text: {
justifyContent: 'center',
fontSize: 24,
paddingBottom: 5,
},
textInput: {
borderWidth: 2,
borderColor: 'black',
minWidth: 260,
marginBottom: 20,
marginHorizontal: 20,
paddingHorizontal: 10,
paddingVertical: 5,
borderRadius: 3,
},
});

I believe the movieList array is your params. Try this in your return statement of HomeScreen.js:
<Text style={styles.heading}>{route.params[0].title}</Text>

this.props.navigation is undefined (createStackNavigator)

I would like to create a simple navigation example on ReactNative.
Here is a code below;
import React, { Component } from 'react';
import { Button, View, Text } from 'react-native';
import { createStackNavigator } from 'react-navigation-stack';
class Home extends React.Component {
render() {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Home</Text>
<Button
title="To the detail Page"
onPress={() => this.props.navigation.navigate('DetailScreen')}
/>
</View>
);
}
}
class Detail extends React.Component {
render() {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Detail Page</Text>
</View>
);
}
}
export default createStackNavigator({
HomeScreen: { screen: Home },
DetailScreen: { screen: Detail },
})
When I code like this, an error is occurred as Line12 this.props.navigation is undefined.
Does anyone have a solution?

Please try the below code :
import React, { Component } from 'react';
import { Button, View, Text } from 'react-native';
import {
createAppContainer
} from 'react-navigation';
import { createStackNavigator } from 'react-navigation-stack';
class Home extends React.Component {
render() {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Home</Text>
<Button
title="To the detail Page"
onPress={() => this.props.navigation.navigate('DetailScreen')}
/>
</View>
);
}
}
class Detail extends React.Component {
render() {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Detail Page</Text>
</View>
);
}
}
const APpStack = createStackNavigator({
HomeScreen: { screen: Home },
DetailScreen: { screen: Detail },
})
const App = createAppContainer(APpStack);
export default App;
You can also check the working solution link expo
hope it helps. feel free for doubts

You need a constructor to define properties that are used for storing navigation data (among others):
class Home extends React.Component {
constructor(props) {
super(props);
// ...
}

Why my text is not displaying in the center?

I started playing with react-native and I got a problem with centering a text, it's a very simple code but idk why it's not working
I was playing with animations too and none of all the examples that I did didn't work
So I have a View with a Text and the styles, with the flex should be enought, but isn't
import React, { Component } from 'react';
import { StyleSheet, Text, View } from 'react-native';
export default class HomeView extends Component {
render(){
return(
<View style={styles.container}>
<Text style={styles.welcome}>Hello World</Text>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#F5FCFF',
alignItems: 'center',
justifyContent: 'center',
},
welcome: {
fontSize: 20,
textAlign: 'center',
margin: 10
}
});
Here is the App class
import React from 'react';
import { StyleSheet,View} from 'react-native';
import HomeView from './components/HomeView';
const App = () => {
return (
<View>
<HomeView/>
</View>
);
};
const styles = StyleSheet.create({
container: {
flex: 1,
},
});
export default App;
And the index.js
import {AppRegistry} from 'react-native';
import App from './App';
import {name as appName} from './app.json';
AppRegistry.registerComponent(appName, () => App);

You are not closing your class with } after render().

Inside of the App class you need to render the View with container style
so it would be
const App = () => {
return (
<View style={styles.container}>
<HomeView/>
</View>
);
};
so it has flex: 1 and then can take the full space and align itself properly.

Navigating between screens having two separate react native files

I am new to react native and I want to navigate between screens. I have two sample files
#App.js
import React from 'react';
import { StyleSheet, Text, View } from 'react-native';
import Home from './src/Home';
export default class App extends React.Component {
render() {
return (
<View style={styles.container}>
<Home/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#FFEB3B',
alignItems: 'center',
justifyContent: 'center',
},
});
and another file
#Home.js
import React from 'react';
import { StyleSheet, Text, View, TouchableOpacity} from 'react-native';
export default class Home extends React.Component {
render() {
return (
<View style={styles.container}>
<TouchableOpacity style={styles.button}>
<Text style={styles.buttonText}>User</Text>
</TouchableOpacity>
<TouchableOpacity style={styles.button}>
<Text style={styles.buttonText}>Contractor</Text>
</TouchableOpacity>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
alignItems: 'center',
justifyContent: 'center',
},
buttonText: {
fontSize:16,
fontWeight:'500',
color:'#212121',
textAlign:'center'
},
button: {
width:300,
borderRadius: 25,
backgroundColor:'#FCE4EC',
marginVertical: 10,
paddingVertical:16
}
});
How do I make it that when either User or Contractor are clicked in Home.js file they take me to different screens preferably using stacknavigator. I tried the documentation but can't seem to figure out the way forward.

You could do this easily using StackNavigator offered by react-navigation library.
Here is the idea:
In the App.js file you have to refer to the stacknavigator/parent of your navigation.
#App.js
import React from 'react';
import { StyleSheet, Text, View } from 'react-native';
import { StackNavigator } from 'react-navigation';
import Home from './src/Home';
import Contractor from './src/Contractor';
import User from './src/User';
const Main = StackNavigator({
HomeScreen: {
screen: Home
},
UserScreen: {
screen: User,
},
ContractorScreen: {
screen: Contractor,
},
}
export default class App extends React.Component {
render() {
return (
<View style={styles.container}>
<Main/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#FFEB3B',
alignItems: 'center',
justifyContent: 'center',
},
});
Home file:
#Home.js
import React from 'react';
import { StyleSheet, Text, View, TouchableOpacity} from 'react-native';
export default class Home extends React.Component {
render() {
return (
<View style={styles.container}>
<TouchableOpacity style={styles.button}
onPress={() => this.props.navigation.navigate({ routeName: 'UserScreen'})}>
<Text style={styles.buttonText}>User</Text>
</TouchableOpacity>
<TouchableOpacity style={styles.button}
onPress={() => this.props.navigation.navigate({ routeName: 'ContractorScreen'})}>
<Text style={styles.buttonText}>Contractor</Text>
</TouchableOpacity>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
alignItems: 'center',
justifyContent: 'center',
},
buttonText: {
fontSize:16,
fontWeight:'500',
color:'#212121',
textAlign:'center'
},
button: {
width:300,
borderRadius: 25,
backgroundColor:'#FCE4EC',
marginVertical: 10,
paddingVertical:16
}
});
User file:
#User.js
import React from 'react';
import { StyleSheet, Text, View, TouchableOpacity} from 'react-native';
export default class User extends React.Component {
render() {
return (
<View style={styles.container}>
<Text style={styles.text}>I am the User screen</Text>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
alignItems: 'center',
justifyContent: 'center',
},
text: {
fontSize:16,
fontWeight:'500',
color:'#212121',
textAlign:'center'
});
And finally, Contractor file:
#Contractor.js
import React from 'react';
import { StyleSheet, Text, View, TouchableOpacity} from 'react-native';
export default class Contractor extends React.Component {
render() {
return (
<View style={styles.container}>
<Text style={styles.text}>I am the Contractor screen</Text>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
alignItems: 'center',
justifyContent: 'center',
},
text: {
fontSize:16,
fontWeight:'500',
color:'#212121',
textAlign:'center'
});

How to add mapStateToProps / redux to react-navigation TabNavigator?

I want to build the very simple example shown here: https://reactnavigation.org/docs/tab-based-navigation.html
import React from 'react';
import { Text, View } from 'react-native';
import { TabNavigator } from 'react-navigation'; // 1.0.0-beta.27
class HomeScreen extends React.Component {
render() {
return (
<View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
<Text>Home!</Text>
</View>
);
}
}
class SettingsScreen extends React.Component {
render() {
return (
<View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
<Text>Settings!</Text>
</View>
);
}
}
export default TabNavigator({
Home: { screen: HomeScreen },
Settings: { screen: SettingsScreen },
});
How would I go about wrapping the tab navigator in mapStateToProps (or any stack navigator). For example if I want to use dynamic tab names for a specific tab.
Thanks.

const MainRoot =(props) => {
const myTabbar = TabNavigator({
Home: LoginForm,
Settings: RegistrationForm,
third: TabsView
},{
initialRouteName: props.myName
}
);
return <CustomTabNavigator/>;
}
const mapStateToProps = state => ({
myName: state.LibraryMain,
});
export default connect(mapStateToProps)(MainRoot)