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Homescreen (App.js) structure for react-navigation

I'm trying to implement the react-navigation package to make one screen link to another. I'm getting an error "undefined is not an object (evaluating '_this2.props.navigation.navigate') - React Native"
I'm fairly sure this error is because I have nothing in the App.js part of my project.
I have a file called screen.js that has two classes (one for each screen), and an onpress function that calls the this.props.navigator to change screens.
Screen.js
import React, { Component } from 'react';
import {
StyleSheet,
Text,
TextInput,
View,
TouchableHighlight,
PanResponder,
AppRegistry,
Image,
Alert,
} from 'react-native';
import { Card, Button, Icon } from 'react-native-elements';
import { createStackNavigator, createAppContainer } from 'react-navigation';
import { Constants, MapView } from 'expo';
class HomeScreen extends Component {
static navigationOptions = {
title: 'Home',
};
constructor() {
super();
this.state = {...};
}
_handleButtonPress = () => {
Alert.alert('Button pressed!', 'You did it!');
};
componentWillMount() {
this.panResponderRef = PanResponder.create({
onStartShouldSetPanResponder: () => true,
onMoveShouldSetPanResponder: () => true,
onPanResponderGrant: this.doNothing,
onPanResponderMove: this._handlePanResponderMove,
onPanResponderRelease: this._handlePanResponderEnd,
onPanResponderTerminate: this.doNothing,
});
}
//onPanResponderRelease and onPanResponderTerminate Handler
_handlePanResponderEnd = (event, gestureState) => {
const { navigate } = this.props.navigation;
let tIndex = this.state.index;
if (this.state.dy > 100)
navigate('Second', { index: tIndex, getFunc: this.getName.bind(this) });
else if (this.state.dx > 150) this.setState({ index: tIndex + 1 });
else if (this.state.dx < -150 && tIndex > 0)
this.setState({ index: tIndex - 1 });
};
render() {
const { navigate } = this.props.navigation;
return (
<View style={styles.container}>
<TouchableHighlight
style={styles.TouchableHighlight}
onPress={() => this.props.navigator.push({id:'SecondScreen'})}>
<View style={styles.author}>
<Text style={styles.author}>Shelter 1</Text>
</View>
</TouchableHighlight>
</View>
);
}
}
class SecondScreen extends React.Component {
static navigationOptions = {
title: 'Second',
};
constructor(props) {
super(props);
this.state = {
index: this.props.navigation.state.params.index,
getFunc: this.props.navigation.state.params.getFunc,
name: 'not set'
};
}
componentWillMount() {
let tName = this.state.getFunc(this.state.index);
this.setState({ name: tName });
}
render() {
const { navigate } = this.props.navigation;
return (
<View style={styles.container}>
</View>
<Button title="Go to Home page" onPress={() => navigate('Home')} />
</View>
);
}
}
const NavigationApp = createStackNavigator({
Home: { screen: HomeScreen },
Second: { screen: SecondScreen },
});
export default createAppContainer(NavigationApp);
});
App.js
import NavApp from "screen";
export default NavApp;
I am getting an error "undefined is not an object (evaluating '_this2.props.navigator.push')"

You could try this
this.props.navigation.push('SecondScreen')

React Native - Can't display the Data in other screen

What I want to achieve is display the datas in other screen or another component with React Redux. I'm using the latest version of React Redux and Redux.
My problem is every time I want to display the data, or when I press the button (TouchableOpacity) in EventCreator.js it doesn't display. I tried to check all of my codes but I don't see any typo or any wrong codes.
Feel free to ask for more of my codes. Thank you!
UPDATE: I tried all codes to my another new project, but with RNNV1. So it might be some new codes for RNNv2 that is related to React Redux to change. I prefer to all viewers to focus check my codes about RNNv2 connected to React Redux. Thank you!
These are my codes:
App.js, all my Registered Screens.
import {Navigation} from 'react-native-navigation';
import React from 'react';
//Screens
import AuthScreen from './src/screens/Auth/Auth';
import EventMap from './src/screens/Map/Map';
import EventCreator from './src/screens/EventCreator/EventCreator';
import EventHome from './src/screens/Home/Home';
import EventPushScreen from './src/screens/EventPushScreen/EventPushSc';
//Redux
import { Provider } from 'react-redux';
import configureStore from './src/store/configureStore';
const store = configureStore();
//Register Screens
Navigation.registerComponentWithRedux("Event.AuthScreen", () => AuthScreen);
Navigation.registerComponentWithRedux("Event.Map", () => EventMap);
Navigation.registerComponent("EventCreator", () => (props) => (
<Provider store={store}>
<EventCreator {...props}/>
</Provider>
), () => EventCreator);
Navigation.registerComponent("EventHome", () => (props) => (
<Provider store={store}>
<EventHome {...props}/>
</Provider>
), () => EventHome);
//Start A App
Navigation.events().registerAppLaunchedListener(() => {
Navigation.setRoot({
root: {
stack: {
children: [{
component: {
name: "Event.AuthScreen",
}
}],
options: {
topBar: {
title: {
text: 'Welcome',
alignment: 'center'
}
}
}
}
}
});
});
This is my 1st Screen where the TextInput and Button (TouchableOpacity) is.
EventCreator.js
import EventInput from '../../components/EventInput';
class EventCreator extends Component {
eventAddedHandler = (eventName) => {
this.props.onAddEvent(eventName);
};
render() {
return (
<View style={styles.container}>
<EventInput onEventAdded={this.eventAddedHandler}/>
</View>
);
}
};
const mapDispatchToProps = dispatch => {
return {
onAddEvent: (eventName) => dispatch(addEvent(eventName))
};
};
export default connect(null, mapDispatchToProps)(EventCreator);
EventInput.js, This is my Component that is connected to EventCreate.js
class EventInput extends Component {
state = {
eventName: ""
};
eventNameChangedHandler = (val) => {
this.setState({
eventName: val
});
};
eventSubmitHandler = () => {
if (this.state.eventName.trim() === "") {
return;
}
this.props.onEventAdded(this.state.eventName);
};
render () {
return (
<View style={styles.inputAndButtonContainer}>
<TextInput
placeholder="Create your event"
value={this.state.eventName}
onChangeText={this.eventNameChangedHandler}
style={styles.textInputContainer}
/>
<TouchableOpacity onPress={this.eventSubmitHandler}>
<View style={styles.buttonContainer}>
<Text style={{color: 'black'}}>Add</Text>
</View>
</TouchableOpacity>
</View>
);
}
};
Home.js, this is where I want to display may Data or the FlatList.
class Home extends Component {
eventSelectedHandler = key => {
const selEvent = this.props.events.find(event => {
return event.key === key;
});
Navigation.push("EventHomeStack", {
component: {
name: "EventPushScreen",
passProps: {
selectedEvent: selEvent
},
options: {
topBar: {
title: {
text: selEvent.name
}
}
}
}
});
};
render() {
return (
<View>
<EventList
events={this.props.events}
onItemSelected={this.eventSelectedHandler}
/>
</View>
);
}
};
const mapStateToProps = state => {
return {
events: state.events.events
};
};
export default connect(mapStateToProps)(Home);
EventList.js, another Component connected to Home.js
import ListItem from './ListItem';
const eventList = (props) => {
return (
<FlatList
style={styles.listContainer}
data={props.events}
renderItem={(info) => (
<ListItem
eventName={info.item.name}
eventImage={info.item.image}
onItemPressed={() => props.onItemSelected(info.item.key)}
/>
)}
/>
);
};
export default eventList;
listItem.js, another Component connected to EventList.js
const listItem = (props) => (
<TouchableOpacity onPress={props.onItemPressed}>
<View style={styles.listItem}>
<Image resizeMode="cover" source={props.eventImage} style={styles.eventImage}/>
<Text>
{props.eventName}
</Text>
</View>
</TouchableOpacity>
);
export default listItem;
events.js (reducer)
import {ADD_EVENT, DELETE_EVENT} from '../actions/actionTypes';
const initialState = {
events: []
};
const reducer = (state = initialState, action) => {
switch(action.type) {
case ADD_EVENT:
return {
...state,
events: state.events.concat({
key: `${Math.random()}`,
name: action.eventName,
image: {
uri: "https://c1.staticflickr.com/5/4096/4744241983_34023bf303_b.jpg"
}
})
};
case DELETE_EVENT:
return {
...state,
events: state.events.filter(event => {
return event.key !== action.eventKey;
})
};
default:
return state;
}
};
export default reducer;

How To Get Props in another Screen in react navigation?

I have an issue with react-navigation in passing the props to another screen,
I need to pass some props to Detail screen when the user presses one of the List Places I need to push screen with some details about the place like a Name of place and Image of place,
Errors :
this is my Code
Reducer
import { ADD_PLACE, DELETE_PLACE } from "../actions/actionTypes";
const initialState = {
places: []
};
import placeImage from "../../assets/img.jpg";
const reducer = (state = initialState, action) => {
switch (action.type) {
case ADD_PLACE:
return {
...state,
places: state.places.concat({
key: Math.random(),
name: action.placeName,
// image: placeImage,
image: {
uri:
"https://images.unsplash.com/photo-1530009078773-9bf8a2f270c6?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=750&q=80"
}
})
};
case DELETE_PLACE:
return {
...state,
places: state.places.filter(place => {
return place.key !== state.selectedPlace.key;
})
};
default:
return state;
}
};
export default reducer;
Place List Component
import React from "react";
import { FlatList, StyleSheet, ScrollView } from "react-native";
import ListItem from "../ListItem/ListItem";
const PlaceList = props => {
return (
<FlatList
style={styles.listContainer}
data={props.places}
renderItem={info => (
<ListItem
placeName={info.item.name}
placeImage={info.item.image}
onItemPressed={() => props.onItemSelected(info.item.key)}
/>
)}
keyExtractor={index => String(index)}
/>
);
};
export default PlaceList;
Find Place Screen
import React, { Component } from "react";
import { View, Text } from "react-native";
import { connect } from "react-redux";
import { StackActions } from "react-navigation";
import PlaceList from "../../Components/PlaceList/PlaceList";
class FindPlaceScreen extends Component {
constructor() {
super();
}
itemSelectedHandler = key => {
const selPlace = this.props.places.find(place => {
return place.key === key;
});
this.props.navigation.push("PlaceDetail", {
selectedPlace: selPlace,
name: selPlace.name,
image: selPlace.image
});
};
render() {
return (
<View>
<PlaceList
places={this.props.places}
onItemSelected={this.itemSelectedHandler}
/>
</View>
);
}
}
const mapStateToProps = state => {
return {
places: state.places.places
};
};
export default connect(mapStateToProps)(FindPlaceScreen);
Place Details Screen
import React, { Component } from "react";
import { View, Text, Image, TouchableOpacity, StyleSheet } from "react-native";
import Icon from "react-native-vector-icons/Ionicons";
class PlaceDetail extends Component {
constructor(props) {
super(props);
}
render() {
return (
<View style={styles.modalContainer}>
<View>
<Image
source={this.props.navigation.state.params.image}
style={styles.placeImage}
/>
<Text style={styles.placeName}>
{this.props.navigation.state.params.namePlace}
</Text>
</View>
<View>
<TouchableOpacity onPress={props.onItemDeleted}>
<View style={styles.deleteButton}>
<Icon size={30} name="ios-trash" color="red" />
</View>
</TouchableOpacity>
<TouchableOpacity onPress={props.onModalClosed}>
<View style={styles.deleteButton}>
<Icon size={30} name="ios-close" color="red" />
</View>
</TouchableOpacity>
</View>
</View>
);
}
}
export default PlaceDetail;

You need to use react-native-navigation v2 for the find place screen
itemSelectedHandler = key => {
const selPlace = this.props.places.find(place => {
return place.key === key;
});
Navigation.push(this.props.componentId, {
component: {
name: 'PlaceDetail',
options: {
topBar: {
title: {
text: selPlace.name
}
}
},
passProps: {
selectedPlace: selPlace
}
}
});
};
make sure you import { Navigation } from "react-native-navigation";

Your PlaceDetail has some error
<TouchableOpacity onPress={props.onItemDeleted}>
<TouchableOpacity onPress={props.onModalClosed}>
Change props to this.props
<TouchableOpacity onPress={this.props.onItemDeleted}>
<TouchableOpacity onPress={this.props.onModalClosed}>
But I don't see onItemDeleted and onModalClosed anywhere, don't forget to pass those to PlaceDetail via props as well :)

React-navigation how to pass data down to navigator objects

Consider the following example:
import { AppRegistry } from "react-native";
import React, { Component } from "react";
import {
createSwitchNavigator,
createStackNavigator,
createBottomTabNavigator
} from "react-navigation";
import Icon from "react-native-vector-icons/Ionicons";
import { withNavigation } from "react-navigation";
import {
View,
Text,
Platform,
TouchableNativeFeedback,
TouchableOpacity,
StyleSheet
} from "react-native";
const Touchable =
Platform.OS === "android" ? TouchableNativeFeedback : TouchableOpacity;
class ListComponent extends Component {
static navigationOptions = {
title: "List"
};
handleGo = () => {
this.props.navigation.navigate("Board");
};
render = () => {
//??? How to get myData ???
return (
<View>
<Text>HELLO LIST!!!!</Text>
<Touchable onPress={this.handleGo}>
<Text>GO TO BOARD</Text>
</Touchable>
<Text>{myData}</Text>
</View>
);
};
}
const List = withNavigation(ListComponent);
class BoardComponent extends Component {
static navigationOptions = {
title: "Board"
};
//??? How to get myData ???
render = () => {
return (
<View>
<Text>HELLO BOARD!!!!</Text>
<Text>{myData}</Text>
</View>
);
};
}
const Board = BoardComponent;
class PanelComponent extends Component {
static navigationOptions = {
title: "Panel"
};
//??? How to get myData ???
render = () => {
return (
<View>
<Text>HELLO PANEL!!!!</Text>
<Text>{myData}</Text>
</View>
);
};
}
const Panel = PanelComponent;
const Test0 = createStackNavigator(
{
List: {
screen: List
},
Board: {
screen: Board
}
},
{
navigationOptions: {
headerStyle: {
backgroundColor: "grey"
},
headerTintColor: "blue",
headerTitleStyle: {
fontWeight: "bold"
}
}
}
);
const Test1 = createStackNavigator(
{
Panel: {
screen: Panel
}
},
{
navigationOptions: {
headerStyle: {
backgroundColor: "grey"
},
headerTintColor: "blue",
headerTitleStyle: {
fontWeight: "bold"
}
}
}
);
const LoggedInNavigator = createBottomTabNavigator(
{
Test0: {
screen: Test0,
navigationOptions: {
tabBarIcon: ({ tintColor, focused }) => (
<Icon
name={"ios-list-box-outline"}
size={24}
color={"#cdcdcd"}
/>
)
}
},
Test1: {
screen: Test1,
navigationOptions: {
tabBarIcon: ({ tintColor, focused }) => (
<Icon
name={"ios-construct-outline"}
size={24}
color={"#cdcdcd"}
/>
)
}
}
},
{
tabBarOptions: {
showLabel: false,
activeTintColor: "white",
activeBackgroundColor: "blue",
style: {
backgroundColor: "grey"
}
},
animationEnabled: true,
swipeEnabled: true,
initialRouteName: "Test1"
}
);
export const createRootNavigator = () => {
let myData = getMyDataFromDB(); // <=== How can I pass myData down to Panel/Board/List
return createSwitchNavigator(
{
LoggedIn: {
screen: LoggedInNavigator
}
},
{
initialRouteName: "LoggedIn"
}
);
};
class App extends Component {
render = () => {
const Layout = createRootNavigator();
return <Layout />;
};
}
export default App;
AppRegistry.registerComponent("app", () => App);
How can I pass down myData through all the routes to the end components?
This is a skeleton of a much bigger application where I query for data on the root navigator (createRootNavigator) that must be served to some components down the navigation tree.

You could make a Higher Order Component or a wrapper component that handles the fetching of your data in componentDidMount and wrap all your routes with it
// HOC component example
import React from 'react';
const withMyData = (WrappedComponent) => {
class myEnchancedComponent extends React.Component {
state ={ myData: null }
componentDidMount() {
let myData = getMyDataFromDB();
// set the state after you get the data
this.setState({myData})
}
render() {
const {myData} = this.state;
return (
<WrappedComponent {...this.props} myData={myData}
/>
);
}
}
return myEnchancedComponent;
};
export default withMyData;
// example of how to use it
const List = withMyData(withNavigation(ListComponent));
The are other ways you can solve this too. You could use redux combined with redux-persist to store your data and make them available even offline.

He you can use redux for that, or another way is using local storage (react-native-local-storage), with this lib you can storage any data and in any moment or page you can access it.

Issue with photos length

I am facing 2 issues related to length of my selected photos:
When selecting photos, it lets me to select 5 photos without any issue (it fits my length restriction), however it doesn't save the chosen photos, when I go to the next screen. In another scenario, when I am at the same screen where I choose photos and I choose 6 photos, it selects the 6 photo but the warning popup will appear and say that its currently supports 5, then when I go to next screen its saves the selected photos unlike previously.
If I deselect photos and then try to select another photos (still in my length limit) popup jumps with selection limit and doesn't let me choose photos, when I go to the next screen it saves the changes from previous selection and not from current one.
import React from 'react';
import {
View,
ScrollView,
Image,
Dimensions,
TextInput,
Text,
StatusBar,
TouchableHighlight,
Linking,
Keyboard,
CameraRoll,
KeyboardAvoidingView
} from 'react-native';
import {connect} from 'react-redux';
import {ActionCreators} from '../redux/actions';
import {bindActionCreators} from 'redux';
import Colors from '../constants/Colors';
import api from '../api';
import {
getEmailAddress,
showError,
renderMessageBar,
registerMessageBar,
unregisterMessageBar
} from '../utils/ComponentUtils';
import {
regularHeader,
mainHeader
} from '../utils/Headers';
import {NavigationActions} from 'react-navigation';
import {SelectionLimitDialog} from '../utils/Dialogs';
import {ifIphoneX, isIphoneX} from 'react-native-iphone-x-helper';
import {SafeAreaView} from 'react-navigation';
// specific component imports.
import {List, ListItem} from 'react-native-elements'
import {Button} from 'react-native-elements'
import Loader from '../components/Loader';
import LoaderError from '../components/LoaderError';
import SelectedPhoto from '../components/SelectedPhoto';
class MultiSafeeScreen extends React.Component
{
static navigationOptions = ({navigation}) => {
const {params} = navigation.state;
const isIncome = params ? params.isIncome : false;
const notificationAction = params ? params.notificationAction : () => {};
const isShowBack = params ? params.isShowBack : false;
return mainHeader({
isShowBack: isShowBack,
backAction: () => navigation.goBack(),
notificationAction: () => notificationAction(),
income: isIncome
});
};
constructor(props) {
super(props);
this.selectedPhotos = [];
this.state = {
photos: null,
loader: {
loading: 0,
message: "Loading photos..."
},
selectedPhotos: [],
supportLength: 5
};
this.props.navigation.setParams({notificationAction: this.onNotification, isIncome: this.props.isNewNotifications});
}
UNSAFE_componentWillReceiveProps(newProps) {
if (newProps.isNewNotifications !== this.props.isNewNotifications) {
this.props.navigation.setParams({notificationAction: this.onNotification, isIncome: newProps.isNewNotifications});
}
}
componentDidMount() {
registerMessageBar(this.refs.alert);
let options = {
first: 30,
assetType: 'Photos',
}
CameraRoll.getPhotos(options)
.then(r => {
this.setState({
photos: r.edges,
loader: {
loading: 1,
message: "Loading photos..."
},
});
})
.catch((err) => {
//Error Loading Images
});
StatusBar.setHidden(false);
}
componentWillUnmount() {
unregisterMessageBar();
this.props.setSelectedPhotos(0);
}
onNotification = () => {
this.props.setNewNotifications(false);
this.props.navigation.navigate("Notifications");
}
closeKeyboard = () => {
Keyboard.dismiss();
}
onSelectPhoto = (photo, index) => {
let photos = new Set([...this.selectedPhotos]);
let len = photos.size + 1 ;
console.log('photos')
if (len > this.state.supportLength) {
this.limitDialog.open();
this.setState({selectedPhotos: this.selectedPhotos});
this.props.setSelectedPhotos(len);
}
else {
photos.add(photo);
this.selectedPhotos = Array.from(photos);
}
}
onDeselectPhoto = (photo, index) => {
let photos = new Set([...this.state.selectedPhotos]);
let len = photos.size - 1;
photos.delete(photo);
this.setState({selectedPhotos: Array.from(photos)});
this.props.setSelectedPhotos(len);
}
onNext = () => {
this.props.navigation.navigate("MultiSafeeCreate", {
isShowBack: true,
selected: [...this.state.selectedPhotos]
});
}
renderLoader() {
let {width, height} = Dimensions.get('window');
let photoWidth = width/3;
if (this.state.loader.loading === 0) {
return <Loader style={{justifyContent: 'center', alignItems: 'center'}} message={this.state.loader.message}/>
}
else if (this.state.loader.loading === 2) {
return <LoaderError style={{justifyContent: 'center', alignItems: 'center'}} message={this.state.loader.message}/>
}
// if photos are null do nothing, else if empty show onbording
// if has photos show photos.
if (this.state.photos === null) {
return <Loader style={{justifyContent: 'center', alignItems: 'center'}} message={this.state.loader.message}/>
}
else {
return (
<View style={{width: width, maxHeight: 600}}>
<ScrollView >
<View style={{flexDirection: 'row', width: width, flexWrap: 'wrap',marginBottom:40, justifyContent: 'space-between'}}>
{
this.state.photos.map((p, i) => {
return (
<SelectedPhoto
key={i}
index={i}
style={{
width: photoWidth,
height: photoWidth,
}}
borderColor = "white"
limit={this.state.supportLength}
photo={p}
onSelectPhoto={this.onSelectPhoto}
onDeselectPhoto={this.onDeselectPhoto}
/>
);
})
}
</View>
</ScrollView>
<View style={{ position:'absolute', right:-15, top:475 }}>
<Button
onPress={this.onNext}
containerViewStyle={{width: width}}
backgroundColor={Colors.red}
title='NEXT' />
</View>
</View>
);
}
}
render() {
return (
<View style={{flex: 1, backgroundColor: Colors.white}}>
{this.renderLoader()}
<SelectionLimitDialog ref={(el) => this.limitDialog = el} />
{renderMessageBar()}
</View>
);
}
}
function mapDispatchToProps(dispatch) {
return bindActionCreators(ActionCreators, dispatch);
}
function mapStatesToProps(state) {
return {
isNewNotifications: state.isNewNotifications
};
}
export default connect(mapStatesToProps, mapDispatchToProps)(MultiSafeeScreen);