Accessing navigation props - react-navigation - react-native

I just have a question regarding react-navigation.
I understand that the navigation props becomes accessible when a screen is rendered from the stacknavigator.
But how do you access the navigation props if the screen is not rendered by the stacknavigator?
Like this:
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import {
StyleSheet,
Text,
View,
} from 'react-native';
import Swiper from 'react-native-swiper';
import Menu from './Menu';
class HomeSwiper extends Component {
static propTypes = {
navigation: PropTypes.object,
};
render() {
return (
<Swiper showsButtons>
<View>
<Menu
navigationProps={this.props.navigation}
/>
</View>
<View>
<Text>Hello Swiper</Text>
</View>
</Swiper>
);
}
}
export default HomeSwiper;
Wherein Menu is:
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import { AsyncStorage, TouchableOpacity, Text, BackHandler, Alert } from 'react-native';
import { StandardContainerIOS } from '../components/Container';
import { StandardButton } from '../components/Buttons/';
class Menu extends Component {
static propTypes = {
navigation: PropTypes.object,
};
static navigationOptions = ({ navigation }) => {
const { params = {} } = navigation.state;
const headerLeft = (
<TouchableOpacity
onPress={params.handleRedirect ? params.handleRedirect : () => null}
>
<Text>Logout</Text>
</TouchableOpacity>
);
return {
headerLeft,
};
};
constructor(props) {
super(props);
this.state = {
email: '',
petName: [],
numberOfPets: '',
};
}
getInitialState() {
return {
petName: ['No Name'],
};
}
async componentWillMount() {
try {
const value = await AsyncStorage.getItem('email');
if (value !== null) {
// We have data!!
}
} catch (error) {
// Error retrieving data
}
this.props.navigation.setParams({
handleRedirect: this.handlePressLogout,
});
this.getEmail();
BackHandler.addEventListener('hardwareBackPress', this.handleBackButton);
}
componentWillUnmount() {
BackHandler.removeEventListener('hardwareBackPress', this.handleBackButton);
}
render() {
return (
<StandardContainerIOS>
<StandardButton backgroundColor="#6D4C41" title="View Pet" onPress={this.handleIndexView} />
<StandardButton backgroundColor="#6D4C41" title="Register Pet" onPress={this.handlePressRegisterPets} />
<StandardButton backgroundColor="#6D4C41" title="Logout" onPress={this.handlePressLogout} />
</StandardContainerIOS>
);
}
}
export default Menu;
I've removed the other function definition to cut the post a little shorter. The Menu screen was working fine when it was rendered from the stacknavigator. Im trying to incorporate swiping in my app.
Any suggestions?

Related

Unable to load provider from react-redux module in react native

I am creating a slide bar, In that, I have used the react-redux library. When I call the class which contains the redux-code, it works fine. I want to show this slide bar after login. Therefore, with conditions (I set a state variable if user login successfully then only this page should get rendered), I tried to call the same file which shows a blank page. I printed the console log. I am able to print all the logs. But with conditions, I am not able to load the data.
I don't know much about react-redux.Can you assist me to resolve this?
My code is,
main.js,
import React, {Component} from 'react';
import {
StyleSheet,
Dimensions,
Platform,
View,
StatusBar,
DrawerLayoutAndroid,
} from 'react-native';
import { createStore } from 'redux';
import { Provider } from 'react-redux';
import reducer from '../Redux/reducers';
import { setNavigator, setActiveRoute } from "../Redux/actions";
import DrawerContent from '../Navigation/DrawerContent';
import Toolbar from '../Navigation/Toolbar';
import AppNavigation from '../Navigation/AppNavigation';
import { bgStatusBar, bgDrawer } from '../global.styles';
let store = createStore(reducer);
/* getDrawerWidth Default drawer width is screen width - header width
* https://material.io/guidelines/patterns/navigation-drawer.html
*/
const getDrawerWidth = () => Dimensions.get('window').width - (Platform.OS === 'android' ? 56 : 64);
export default class Main extends Component {
constructor() {
super();
this.drawer = React.createRef();
this.navigator = React.createRef();
}
componentDidMount() {
store.dispatch(setNavigator(this.navigator.current));
}
openDrawer = () => {
this.drawer.current.openDrawer();
};
closeDrawer = () => {
this.drawer.current.closeDrawer();
};
getActiveRouteName = navigationState => {
if (!navigationState) {
return null;
}
const route = navigationState.routes[navigationState.index];
// dive into nested navigators
if (route.routes) {
return getActiveRouteName(route);
}
return route.routeName;
};
render() {
return (
<Provider store={store}>
<DrawerLayoutAndroid
drawerWidth={getDrawerWidth()}
drawerPosition={DrawerLayoutAndroid.positions.Left}
renderNavigationView={
() => <DrawerContent closeDrawer={this.closeDrawer} />
}
ref={this.drawer}
>
<View style={styles.container}>
<StatusBar
translucent
animated
/>
<Toolbar showMenu={this.openDrawer} />
<AppNavigation
onNavigationStateChange={(prevState, currentState) => {
const currentScreen = this.getActiveRouteName(currentState);
store.dispatch(setActiveRoute(currentScreen));
}}
ref={this.navigator}
/>
</View>
</DrawerLayoutAndroid>
</Provider>
);
}
}
Login.js
import Main from './main';
render() {
return (
<View>
{this.state.isLoggedIn ?
<Main/>
:
<ChangePassword isUpdatePassword={this.state.isUpdatePassword} callLogin={this.callLogin}/>
);
}
}
If I just call Main class inside render method it works. But It does not work with conditions.

Undefined Unstated Container in a React Native Component using React Navigation

My problem is That I want to access a Container in a component but it seems to be undefined.
undefined alert image
I am using Unstated and as you can see this is my code in the container file (login-container.js):
import { Container } from 'unstated'
class LoginContainer extends Container {
constructor(props){
super(props)
this.state = {
stepNumber: 0,
}
}
}
export default new LoginContainer()
And this is app.js:
import React, { Component } from 'react'
import { createStackNavigator, createSwitchNavigator } from 'react-navigation'
import { Provider } from 'unstated'
import LoginContainer from './containers/login-container'
import Home from './screens/home'
import Splash from './screens/splash'
import Login from './screens/login'
import Intro from './screens/intro'
export default class App extends Component {
render() {
return (
<Provider inject={[LoginContainer]}>
<AuthStack/>
</Provider>
)
}
}
const SplashStack = createStackNavigator(...)
const AppStack = createStackNavigator(...)
const AuthStack = createStackNavigator(
{
Intro: { screen: Intro},
Login: { screen: Login}
},
{
headerMode: "none",
initialRouteName: "Intro"
}
)
const SwitchNavigator = createSwitchNavigator(...)
And this would be login.js:
import React, { Component } from 'react'
import { Text, View } from 'react-native'
export default class Login extends Component {
constructor(props){
super(props)
}
render() {
// const { state: {stepNumber} } = this.props.loginContainer
alert(this.props.LoginContainer)
return (
<View>
<Text> someText </Text>
</View>
)
}
}
I previously tried to use Subscribe component to inject the container to my app but I got the same thing I am getting here.
Using
- react-native 0.58.6
- react-navigation 2.13.0 (due to some bugs in v3)
- unstated 2.1.1
What's really great about Unstated is how simple it is to implement.
Just wrap your render component in Unstated's <Subscribe to></Subscribe> tags and you're good to go. Whenever you setState() in the Container, all Components that Subscribe to it get re-rendered with the Container's updated state property values available to them.
import React, { Component } from 'react';
import { Text, View } from 'react-native';
import { Subscribe } from 'unstated';
import LoginContainer from './containers/login-container';
export default class Login extends Component {
constructor(props){
super(props)
}
render() {
return (
<Subscribe to={[LoginContainer, AnotherContainer]}>
{(container, another) => (
<View>
<Text>{container.state.stepNumber}</Text>
</View>
})
</Subscribe>
);
}
}
UPDATE: Or do it in this HOC way. After creating this:
WithUnstated.js
import React, { PureComponent } from "react";
import { Subscribe } from "unstated";
import DefaultStore from "../store/DefaultStore";
const withUnstated = (
WrappedComponent,
Stores = [DefaultStore],
navigationOptions
) =>
class extends PureComponent {
static navigationOptions = navigationOptions;
render() {
return (
<Subscribe to={Stores}>
{(...stores) => {
const allStores = stores.reduce(
(acc, v) => ({ ...acc, [v.displayName]: { ...v } }),
{}
);
return <WrappedComponent {...allStores} {...this.props} />;
}}
</Subscribe>
);
}
};
export default withUnstated;
Then wrap your component like so:
import React, { Component } from 'react';
import { Text, View } from 'react-native';
import { Subscribe } from 'unstated';
import LoginContainer from './containers/login-container';
import AnotherContainer from './containers/another-container';
class Login extends Component {
constructor(props){
super(props)
}
render() {
const {LoginContainer: container} = this.props;
return (
<View>
<Text>{container.state.stepNumber}</Text>
</View>
);
}
}
export default withUnstated(Login, [LoginContainer, AnotherContainer])

'state' is not defined (no-undef)

I am complete noob and am just following a tutorial in react-native on udemy. However, I have reached a wall and cannot find a solution anywhere?
Currently I am getting an error from ESLint showing that state is undefined.
Here is the complete code:
import React, { Component } from 'react';
import { View, Text } from 'react-native';
import axios from 'axios';
class AlbumList extends Component {
state = { albums: [] }; //state is underlined
ComponentWillMount() {
axios.get('https:/rallycoding.herokuapp.com/api/music_albums')
.then(response => this.setState({ albums: response.data }));
}
renderAlbums() {
render() {
console.log(this.state);
return (
<View>
{this.renderAlbums()}
</View>
**strong text**);
}
}
export default AlbumList;
Has there been any update regarding defining 'state' in React-Native?
Sincerely appreciate the help!
Try this out.
import React, { Component } from 'react';
import { View, Text } from 'react-native';
import axios from 'axios';
class AlbumList extends Component {
constructor(props){
super(props);
this.state = {
albums: []
};
this.renderAlbums = this.renderAlbums.bind(this);
}
componentWillMount() {
axios.get('https:/rallycoding.herokuapp.com/api/music_albums')
.then(response => this.setState({ albums: response.data }));
}
renderAlbums() {
return (
<View /> // return your Albums here as you need
);
}
render() {
return (
<View>
{this.renderAlbums()}
</View>
);
}
}
export default AlbumList;

react native pass props to another component

I've been struggling passing a value from one component to another. It's a continuation of the issue from a previous question which was partially resolved: react-native tab navigator search box
I'm using tab navigator and here's my app setup:
index.js (renders tab setup)
  router.js
     searchHeader.js
     tab1.js
     tab2.js
     etc
In index.js when a tab is changed I'm getting the name of the tab. I want to pass that to searchHeader.js to update the placeholder text.
As searchHeader.js isn't imported into index.js and not a direct child how do I pass it that value?
index.js
import React, { Component } from 'react';
import { Root, Tabs } from './config/router';
import { Alert,View } from 'react-native';
class App extends Component {
constructor(props) {
super(props);
this.state = {
searchText: '',
}
}
_getCurrentRouteName(navState) {
if (navState.hasOwnProperty('index')) {
this._getCurrentRouteName(navState.routes[navState.index])
} else {
if (navState.routeName==='One') {
this.setState({searchText:'Search One'})
}
if (navState.routeName==='Two') {
this.setState({searchText:'Search Two'})
}
if (navState.routeName==='Three') {
this.setState({searchText:'Search Three'})
}
if (navState.routeName==='Four') {
this.setState({searchText:'Search Four'})
}
}
}
render() {
return (
<Root onNavigationStateChange={(prevState, newState) => {
this._getCurrentRouteName(newState)
}} />
)
}
}
export default App;
router.js
...
export const Root = StackNavigator({
Tabs: {
screen: Tabs,
navigationOptions: {
header: <SearchHeader data={'Test'} />
}
},
}, {
mode: 'modal',
});
searchHeader.js
import React, { Component } from 'react';
import { View,Text,Dimensions,Alert } from 'react-native';
import { SearchBar } from 'react-native-elements';
class SearchHeader extends Component {
constructor(props) {
super(props);
this.state = {
placeholder: "Search One"
}
}
render() {
return (
<SearchBar
noIcon
containerStyle={{backgroundColor:'#fff'}}
inputStyle={{backgroundColor:'#e3e3e3',}}
lightTheme = {true}
round = {true}
placeholder={data}
placeholderTextColor = '#000'
/>
);
}
};
export default SearchHeader;
You could perhaps pass it as a navigation prop using the setParams method.
An alternative, depending on the scope of your app, would be to look at a state library such as Redux or MobX - but if it's a small app, it's overkill
For that you can use Redux, you will have a store where you can put shared properties and values,
Then your components can connect to that store and bind its props with the chosen reducer(s) and dispatch actions..
this structure may work:
class Home extends Component {
func(val) {
this.setState({value: val});
}
render() {
return (
<View>
<Two func={(val) => this.func(val)} />
</View>
)
}
}
class Two extends Component {
render() {
return (
<View>
<Button title="set" onPress={() => this.props.func('data')} />
</View>
)
}
}

undefined is not an object this.props

I try to use navigation between screen in my RN app. This is my code :
INDEX.ANDROID.JS :
import React, { Component } from 'react';
import {
AppRegistry,
Text,
View ,
Button
} from 'react-native';
import {StackNavigator} from 'react-navigation';
import Login from './app/components/Todo';
const SimpleApp = StackNavigator({
Login: { screen: Todo },
});
export default class aap extends Component {
static navigationOptions = { title: 'Welcome', };
render() {
const { navigate } = this.props.navigation;
return (
<Button onPress ={() => navigate('Todo') } title="go"/>
);
}
}
AppRegistry.registerComponent('aap', () => aap);
here is the code of the second screen TODO.JS
import React, { Component } from 'react';
import {
AppRegistry,
Text,
View ,
Button
} from 'react-native';
export default class Todo extends Component {
render() {
return (
<View>
<Text>
Here is my text
</Text>
</View>
);
}
}
When running my code i get an error : undefined is not an object this.props.naviagtion.
Any help is appreciated
You are not using StackNavigator correctly.
Like #xght said, you should be registering SimpleApp instead of aap. Also, you should be using aap as the initial route to your StackNavigator SimpleApp.
This should look something like this:
import React, { Component } from 'react';
import {
AppRegistry,
Text,
View ,
Button
} from 'react-native';
import {StackNavigator} from 'react-navigation';
import Todo from './app/components/Todo';
class aap extends Component {
static navigationOptions = { title: 'Welcome', };
render() {
const { navigate } = this.props.navigation;
return (
<Button onPress ={() => navigate('Todo') } title="go"/>
);
}
}
const SimpleApp = StackNavigator({
Login: { screen: aap },
Todo: { screen: Todo },
});
AppRegistry.registerComponent('aap', () => SimpleApp);
You registered the wrong component, so the navigator SimpleApp doesn't pass the navigation prop to your component.
Replace
AppRegistry.registerComponent('aap', () => aap); by:
AppRegistry.registerComponent('aap', () => SimpleApp);
And also you forgot to add your aap component in SimpleApp routes. And your import Login from './app/components/Todo';is wrong: Login is the name of the route in SimpleApp, and Todo is the name of the component, so you need to replace it by import Todo...