react-native demo

Get started

• install expo-cli

  markus@marho:~$ npm install -g expo-cli

• install node if you haven't yet (for example via nvm)

  curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash
  nvm install node

• scaffold a new react-native project with expo

  markus@marho:~$expo init
  ? Choose a project name: react-native-demo
  ? Choose a template: blank
  [11:35:41] Extracting project files...
  [11:35:42] Customizing project...
  Your project is ready at /home/markus/react-native-demo
  To get started, you can type:
  
  cd react-native-demo
  expo start

• cd into this folder

  markus@marho:~$ cd react-native-demo

• start expo client

  markus@marho:~$ expo start

Add typescript

• add typescript and react-native-typescript-transformer as dev dependency

  yarn add --dev typescript react-native-typescript-transformer

• add typings

  yarn add --dev @types/react

• add tsconfig.json with minimal config

  {
      "compilerOptions": {
          "target": "es2015",
          "module": "es2015",
          "jsx": "react-native",
          "moduleResolution": "node",
          "allowSyntheticDefaultImports": true
      }
  }
  

• reference the file in the packager options of the expo config in app.json

      "packagerOpts": {
        "sourceExts": [
          "ts",
          "tsx"
        ],
        "transformer": "node_modules/react-native-typescript-transformer/index.js"
      },
  

• add App.tsx

  import React from 'react';
  import {
    Text,
    View
  } from 'react-native';
  
  export default class App extends React.Component {
  
    render() {
      return (
        <View>
          <Text>
            Hello
            </Text>
        </View>
      )
    }
  
  }
  

• Modify App.js to reference App.tsx

  import App from './src/App'
  export default App
  

Add react-navigation

• Add dependency

  yarn add react-navigation
  

• Create a stack navigator and a screen component

  import React from 'react';
  import { View, Text } from 'react-native';
  import { createStackNavigator } from 'react-navigation';
  
  class HomeScreen extends React.Component {
    render() {
      return (
        <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
          <Text>Home Screen</Text>
        </View>
      );
    }
  }
  
  export default createStackNavigator({
    Home: {
      screen: HomeScreen
    },
  });
  

• Add a second screen component and handling navigation between those two screens

import React from 'react';
import { Button, View, Text } from 'react-native';
import { createStackNavigator, NavigationScreenProp } from 'react-navigation';

interface IProps {
  navigation: NavigationScreenProp<any, any>;
}

class HomeScreen extends React.Component<IProps, null> {

  static navigationOptions = ({ navigation }: NavigationScreenProps) => {
    return {
      header: null
    };
  }

  render() {
    return (
      <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
        <Text>Home Screen</Text>
        <Button
          title="Go to Details"
          onPress={() => this.props.navigation.navigate('Details')}
        />
      </View>
    );
  }
}

class DetailsScreen extends React.Component<IProps, null> {

  static navigationOptions = ({ navigation }: NavigationScreenProps) => {
    return {
      title: "DetailsScreen"
    };
  }

  render() {
    return (
      <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
        <Text>Details Screen</Text>
        <Button
          title="Go back"
          onPress={() => this.props.navigation.goBack()}
        />
      </View>
    );
  }
}

const RootStack = createStackNavigator(
  {
    Home: {
      screen: HomeScreen,
    },
    Details: {
      screen: DetailsScreen,
    },
  },
  {
    initialRouteName: 'Home',
  }
);

export default class App extends React.Component {
  render() {
    return <RootStack />;
  }
}

Add state management with mobx

• Add dependencies

  yarn add mobx@4.3.1 mobx-react
  

• Set experimentalDecorators to true in tsconfig.json

          "experimentalDecorators": true,
  

• Setup a store

  class Store {
    @observable color: string = "white";
  
    @action setColor = (color: string) => {
      this.color = color
    }
  }
  const store: Store = new Store();
  

• Interact with the store from the DetailsScreen

    state = {
      color: store.color
    };
  

          <TextInput
            style={{ height: 40, borderColor: 'gray', borderWidth: 1 }}
            onChangeText={(text) => this.setState({ color: text })}
            value={this.state.color}
          />
  

• Interact with the store from the HomeScreen

        <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center', backgroundColor: store.color }}>
  

• For the full source code take a look into this repo.

Create your apk or ipa

• Configure app.json: add android and ios part

    "ios": {
      "supportsTablet": true,
      "bundleIdentifier": "demo.react.native",
      "buildNumber": "1.0.0"
    },
    "android": {
      "package": "demo.react.native",
      "versionCode": 1
    }
  

• Start the build for android

  expo build:android
  

• Start the build for ios

  expo build:android
  

Submit it to the store

• This task is not automated yet - so apk or ipa file must be uploaded to the store by yourself.