React Native Isomorphic app in a weekend

TeamParrot is an app that reads your Slack scrollback out loud so you can listen to your coworkers while doing awesome stuff.

Because I work in a distributed company and have coworkers all around the globe, every day I wake up to a full wall of scrollback to go through. Some of it is actionable, some of it is just chatter, but its good to at least have a vague notion of what is going on.

I also value efficiency and not wasting time, so I came up with TeamParrot.

Having an app in the app store was on my Bucketlist for some time, so I jumped on this simple idea like an angry Twitter user on a chance to humiliate someone.

These days, I usually work with React and React Native seems like an ingenious way to get my feet wet in the pool of app development

Before we even start, I assume you read the official docs – they are pretty decent these days.

Starting a React Native project

Starting an RN project was pretty easy and as many projects these days, starts with a generator.

You have to install RN as a global npm module and then you generete a project, as noted here:

npm install -g react-native-cli
react-native init AwesomeProject
cd AwesomeProject
react-native run-ios

You just provide a name and then the tool creates a project for you.

The project builds in XCode and Android SDK.

Few notes about Android sdk:

  • You DONT need Android studio and it is a terrible piece of software
  • Android SDK is a set of command-line tools
  • These tools install their own libraries, device images, etc. There are multiple versions and each of the files is surprisingly huge. That is one of the reasons that Android development is such a hassle. I would really love some cloud build system
  • Emulating is also a hassle. Genymotion was good solution for me, but you need to point it at the same image files you use to build your software

Renaming a React Native project

Of course I provided a bad name and then had to rename my project. Read about it here:

Using external APIs

Your app needs to connect to an external Oauth? We got you covered!

Using libraries / internal APIs

As you may have heard, React Native does not use WebView like many other JavaScript mobile app technologies ( Cordova for example ).

In RN, higher-order native components ( sometimes big pieces of an app ) are used to piece together you interface. These components have JavaScript wrappers and you can use them as you would any React component. Because these components are pure native, the app behaves just as fast as native. Many components are already wrapped by Facebook in the official repo, even more have sprouted as npm modules. I needed Text-to-speech library for TeamParrot and I found a few.

If you are using a component/library that adds some native code, you need to link it.That means adding the native code parts to the build process of your app. Usually, the automatic tool `rnpm` will do that for you, so when you type

rnpm link


rnpm link library-name

You should be done.

Sometimes it involves few manual steps – putting imports here and there in the native code.

Adding flair

Few pieces like that require fiddling with the native code are Icons and Fonts:

Files structure and isomorphic code 


By default, you will have `index.ios.js` and `` and as you can imagine – one is an entry point for your app in iOS, the other is the entry point for you Android code.

By default, your codebases are separate, but don’t be discouraged! There is one weird trick that programmers will hate you for!

Just put this both in `index.ios.js` and `` :

import { AppRegistry } from ‘react-native’;
import Main from ‘./main’;
AppRegistry.registerComponent( ‘YourApp’, () => Main );

That way, both of your entry points use the same main component.

My folder structure of choice is

  • android
  • app.js – main logic
  • assets
  • components – these are dumb components
  • config
  • index.ios.js
  • index.web.js
  • ios
  • lib
  • login.js
  • node_modules
  • package.json

What is “index.web.js” you ask? Well, this app builds in web too! That means that I can develop my UI in chrome devtools !

Read more about isomorphic prototyping here


Is your App ready for the big day? Not so fast! You have to submit it to the review.

Releasing in App Store

  1. Get Apple developer account
  2. Register yourself in itunesconnect
  3. Create your provisioning keys in XCode
  4. Create a bundle
  5. Sign it
  6. Upload to App store
  7. If you want to invite beta testers, you still need to submit it for a review

You want to update your app post release? Dont forget to configure CodePush! 


 That is an entry even in itself and maybe a post for later!

But with these steps you should be able to make most of the simple apps out there.

Some other valuable links

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

React Native CodePush

CodePush is a magical service that lets you update your app on the fly! It means that when you find a bug in your app you can push the code instantly to your users and update their apps / release new features.

Why should I care?

With Native apps you have to go through app review process every time you release a new version. Sometimes its fast, sometimes its not. But with CodePush you can update JS part of the app bypassing the review!

Me wants!

Setup is actually quite easy and documentation pretty good. You  need to:

  1. Install CLI tools
  2. Register your app
  3. Install CodePush in your app
    npm install --save react-native-code-push
    react-native link react-native-code-push
  4. Wrap your top-level component in a codepush wrapper
    import codePush from "react-native-code-push";
    class TeamParrot extends Component {
    export default codePush( TeamParrot );
  5. Add deployment keys to your project
    1. iOS: add to info.plist:
      your key
  6. To update and rollback your app:
    code-push release-react TeamParrot-ios ios
    code-push promote TeamParrot-ios Staging Production
    code-push rollback TeamParrot-ios Production
  7. Profit

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

React Native: Rename my app

You started building your app before you knew what it was, didn’t you? Well, that is certainly what I did.

My app started as “SlackBird”, then I realized that i may be violating some trademark there ( hint: probably not “bird” ), so I went and changed the name to “TLDR“. But after that I realized my addiction to Party Parrot so “TeamParrot” it is!

So what files should I actually change?


  • When you go to project details in Xcode, you can edit name. When you edit it, Xcode “Rename files” tool opens.Screen Shot 2016-10-19 at 22.37.32 PM.png
  • In ios/PROJECT/info.plist change CFBundleURLName
  • In ios/PROJECT.xcodeproj/xcshareddata/xcschemes/PROJECT.xcschemechangeBuildableName`
  • Rename file ios/PROJECT.xcodeproj/xcshareddata/xcschemes/PROJECT.xcscheme itself to NEWPROJECT.xcsccheme


I just grepped for files containing my old name “TLDR” in this instance. These variables needed to be changed:

  • package in android/app/BUCK
  • applicationId in android/app/build.gradle
  • package in android/app/src/main/AndroidManifest.xml
  • return value of getMainComponentName in android/app/src/main/java/com/slackbird/ . That is the name of your main component in JavaScript portion.
  • package in android/app/src/main/java/com/PROJECT/
  • Application name in android/app/src/main/res/values/strings.xml

React part

Now you renamed your min entry point to your application. So don’t forget to rename your main component name:

AppRegistry.registerComponent( 'TeamParrot', () => Login );

If you renamed everything, some directories will still have old name of your app. I decided I’m fine with that.

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

React Native: Vector Icons – FontAwesome and others

You want some nice icons in your app, don’t you? In my laziness I tried using emojis instead, but it turned out to be sub-par.

So I conceded and installed an icon package called

React Native Vector Icons

npm install react-native-vector-icons --save to install

How this works

This package provides fonts and some wrappers. Since SVG is still not working 100% on RN, introducing vector icons via font seems like a reasonable approach. In mobile apps you want to bundle the font with the app itself.


Theoretically, you should be able to rnpm link. Unfortunately, that didn’t work for me, so I had to install font manually:

  • Drag “Fonts” folder from node_modules/react-native-vector-icons to your project
  • You have to add fonts in info.plist This is how I added FontAwesome only:

UIAppFonts : Fonts/FontAwesome.ttf


In android/app/build.gradle

project.ext.vectoricons = [
    iconFontNames: [ 'FontAwesome.ttf' ] // Name of the font files you want to copy

apply from: "../../node_modules/react-native-vector-icons/fonts.gradle"

In android/settings.gradle :

include ':react-native-vector-icons'

project(':react-native-vector-icons').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-vector-icons/android')


Now you want to plaster icons all over your application, don’t you? I do too!

If you are using Font Awesome like me, you would go to and pick your icon. You need the name without “fa-” at the beginning, and then you drop icon in your project like so:

import Icon from 'react-native-vector-icons/FontAwesome';


Because my project is isomorphic, this caused some problems in the web version. react-native-web is not yet compatible with react-native-vector-icons. To make the project even compile on the web, I made 3 files that abstracted the icon enough:


import React from 'react';
import { Text } from 'react-native';
export default Text; and index.ios.js

import Icon from 'react-native-vector-icons/FontAwesome';
export default Icon;

Because isomorphism works in react native by picking specific files, my project now builds under all 3 environments. Granted, I would prefer it to build for web with working icons, which it does not do currently, but thats a battle for another day.

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

React Native Web & Isomorphic magic

One of the most appealing qualities of React Native is the idea of isomorphic code. Code, that can run on both iOS and Android, enabling you to write 2 apps at the same time.

But, there is another benefit to isomorphic code. You can also speed up writing your code just for one app.

Since react Native is using React code, I initially wanted to develop parts of the application “the React way”, using hot reloading, React Devtools and the fast feedback cycle that web development permits. That would let me work on the app without emulators and building the code.

It’s possible and much more.


‘react-native-web’ builts your react native app as a web app. Not pieces and snippets, but the whole app. Granted, there is a lot of functionality missing, so it’s almost certain that you will have to modify your source a bit to even make the build work, but there is one use-case that it’s perfect for:

UI components.

In TeamParrot I have separated all UI components as “dumb components” without much logic nor dependencies. That way, I can develop UI separately from the whole app. I have made specific container-component for web that holds all of these dumb components and allows me to see all of them in one place, iterate and work on in my web browser.

Let’s do this!

If you want this also for your app, here is how I’ve done it for TeamParrot:


I used react native web boilerplate called react-native-web-starter to get started. I downloaded the latest master, dumped the files into root of TeamParrot project and… Build failed. Now web, ios, and android build stopped working.

Now, let’s fix it!

First need proper libraries in your package.json devDependencies:

"react-native-web": "^0.0.39",
"babel-core": "6.9.1",
"babel-loader": "6.2.4",
"babel-plugin-transform-decorators-legacy": "1.3.4",
"babel-preset-es2015": "6.9.0",
"babel-preset-react": "6.5.0",
"babel-preset-stage-1": "6.5.0",
"babel-runtime": "6.9.2",
"webpack": "1.13.1",
"webpack-dev-server": "1.14.1"

You need to remove .babelrc provided by react-native-web-starter, since that will interfere with RN babel build process. But the configuration from .babelrc needs to end up somewhere, so you need to modify your package.json loader to include:

    test: /\.js$/,
    exclude: /node_modules/,
    loader: 'babel-loader',
    query: {
        cacheDirectory: true,
        "presets": [
        "plugins": [

Everything seems ok at this moment, but the app still does not want to load. After debugging for a while it turned out that these components didnt want to play nice with React Native Web:

  • Switch used for toggles
  • Icon from `react-native-vector-icons`
  • RefreshControl used for “Pull to refresh” on iOS.

I decided on a n ugly solution that I would just render “Text” instead of Icon and not render Switch or RefreshControl at all by passing “webDevelopment” prop:

export default function MainView( { queue, playing, channels, stop, pause, play, refresh, loading, header, openDrawer, webDevelopment = false } ) {
	const msg = get( queue, [ 0, 'items', 0 ] );
	const scrollProps = { style: { flex: 4 } };
	if ( ! webDevelopment ) {
		//When building this component inside react-native-web, RefreshControl does not work correctly
		scrollProps[ 'refreshControl' ] = ;

The last problem I needed to solve was loading images. React Native has a an Image component, to which you pass local images by require prop:

To make this work on web, with webpack, you need to install file-loader:

npm install –save-dev file-loader


it’s located under /web/ :

const path = require('path')
const webpack = require('webpack')

const DIRECTORY = path.join(__dirname)

module.exports = {
    devServer: {
        contentBase: path.join(__dirname, 'src')
    entry: [
        path.join(__dirname, '../index.web.js')
    module: {
        loaders: [
                test: /\.js$/,
                exclude: /node_modules/,
                loader: 'babel-loader',
                query: {
                    cacheDirectory: true,
                    "presets": [
                    "plugins": [
                test: /\.(png|jpg|gif)$/,
                loader: "file-loader?name=img/img-[hash:6].[ext]"
    output: {
        filename: 'bundle.js'
    plugins: [
        new webpack.DefinePlugin({
            'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV || 'development')
        new webpack.optimize.DedupePlugin(),
        new webpack.optimize.OccurenceOrderPlugin()
    resolve: {
        alias: {
            'react-native': 'react-native-web'

Actual web code

This is my index.web.js:

import { AppRegistry } from 'react-native'; import Screens from './web/screens';

AppRegistry.registerComponent('App', () => Screens); AppRegistry.runApplication('App', { rootTag: document.getElementById('react-root') } );

Let’s roll!

And this is how I run my webpack dev server:

webpack-dev-server --port 3000 --config web/ --inline --hot --colors --quiet

Zrzut ekranu 2016-11-12 o 19.37.20.png

Beauty of developing React Native app in devtools

Try it! It really speeds up the whole process!

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

React Native: Oauth

If you want to use any self-respecting API on the web, you are going to need Oauth authentication. If you need an explanation what oauth is, there are plenty better ones. These are the steps your app needs to go through:

  • Send user to special URL in the browser that lets them log in to the service
  • Handle callback URL from this service
  • Exchange keys with the service to make sure callback was legit
  • Store the token.

Since I used Slack API from the slack npm package, I had the “Exchanging the keys” parts ready.

0. Preparing the app

You thought we were going to start from 1, didn’t you? Well, you you must be new to this “programming” stuff. 😃  On the more serious note, you need to register your app in the API provider to get special keys for the step 1 and fill in URL for the step 2.

For TeamParrot, I set up following OAuth redirect URL:

Zrzut ekranu 2016-10-30 o 16.29.31.png

1.Send a user to the special URL

You will need to use “Linking” library. DO NOT confuse Library called “Linking” with the process of “Linking libraries”, which is tying native libraries to JS code. I just send my users to '' + client_id + '&scope=channels:read%20channels:history%20users:read%20channels:write' and that opens web browser with appropriate “back” button.

2. Handling callback URL

If all goes good and your users give you appropriate permissions, they will be sent to the URL you specified in step 0. You may notice that this step has a weird protocol (team-parrot://). It actually can have any protocol you want that’s not used by an other app. This is enabled by “Deep linking” and “Intents” On android.


First, you need to configure your app to handle this specific link you want to capture. That tells the operating system to route those links to your beautiful and shiny app. As per usual, you have to do that in info.plist :


For a reason I completely do not understand, you also have to mess with a bit of Native code. More info in the docs

So, in file ios/SlackBird/AppDelegate.m :

@implementation AppDelegate
+- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {
+  return [RCTLinkingManager application:application openURL:url sourceApplication:sourceApplication annotation:annotation];


Deep linking is called “intents” in Android and much of the same concept applies. You have to tell the OS that you want to open certain protocol inside your app. So:

In android/app/src/main/AndroidManifest.xml

<activity android:name=".MainActivity"
+        android:launchMode="singleTask"
+        <intent-filter>
+          <action android:name="android.intent.action.VIEW" />
+          <category android:name="android.intent.category.DEFAULT" />
+          <category android:name="android.intent.category.BROWSABLE" />
+          <data android:scheme="team-parrot"/>
+      </intent-filter>

OAuth walkthrough

Now you are ready to become a Oauth Sith and step to the dark side. This is how you oauth:

Linking.openURL( '' + client_id + '&scope=channels:read%20channels:history%20users:read%20channels:write' );
Linking.addEventListener( 'url', handleUrl );

And now your function “handleUrl” will be responsible for confirming “CODE” and exchanging it for a token. Usually, that will be handled by your API library of choice. Here is how I did it for TeamParrot:

import { client_id, client_secret } from '../config/slack';
import exchangeCode from 'slack/methods/oauth.access';
import testAuth from 'slack/methods/auth.test';
import { Linking } from 'react-native';

export function login() {
    return new Promise( ( resolve, reject ) => {
        Linking.openURL( '' + client_id + '&scope=channels:read%20channels:history%20users:read%20channels:write' );
        Linking.addEventListener( 'url', handleUrl );
        function handleUrl( event ) {
            const error = event.url.toString().match( /error=([^&]+)/ );
            const code = event.url.toString().match( /code=([^&]+)/ );
            if ( error ) {
                reject( error[ 1 ] );
            } else if ( code ) {
                exchangeCode( { client_id, client_secret, code: code[ 1 ] }, ( err, data ) => err ? reject( err ) : resolve( data ) );
                Linking.removeEventListener( 'url', handleUrl );
            } else {
                reject( 'params' );
    } );

export function testLogin( account ) {
    return new Promise( ( resolve, reject ) => testAuth( { token: account.access_token }, ( err, data ) => {
        if ( err || data.user_id !== account.user_id ) {
            reject( err, data );
        } else {
            resolve( Object.assign( {}, account, data ) );
    } ) );

So there you have it. Now, you should be authenticated over Oauth2 with the slack API and able to make calls.

React Native Isomorphic app over the weekend

This article is part of my “React Native Isomorphic app over the weekend” series. It shares the problems I encountered during development of TeamParrot and Headstart Journal.

  • Oauth
  • Vector Icons – FontAwesome
  • CodePush
  • Renaming an App
  • Web & Isomorphic code development in Chrome devTools
  • Whole story

I wanna be a programmer! A journey.

Ordinary World

Chuck was few years into his career. He was sitting at a desk for most of the day, doing menial and repeatable tasks, filling out Excel spreadsheets and agonizing over “ASAP” PowerPoint presentations that nobody really paid attention to during meetings that were absolutely unnecessary.

But the absolute majority of his day was consumed by Facebook. Be it boredom or burnout, he compulsively checked his stream. And to add salt to the injury, pretty often he would stumble into a story how those fresh-out-of-college programmer-people got an obscene salary, office restaurant, laundry, assistant or something as ridiculous as an office with michelin star-train chefs for YOUR DOG. No, seriously.


Call to adventure


Chuck said to himself: I wanna be a programmer! I have plenty of friends in the industry and I will ask them what to do.

Refusal of the Call


 Lets start with education. I don’t have any formal engineering education! These people had to learn this in school, didn’t they? Maybe it’s not such a great plan, I don’t want to spend another 3 years studying something, do I?

Supernatural Aid


After a chat with one of his friends, he learned that IT is one of those weird professional industries, where formal education is not that important. In many other industries, you show your diploma to convince prospective employer that indeed, you know what you are doing. But in IT, diploma is close to obsolete because the education has trouble keeping with technological progress.

You don’t need formal engineering education

Furthermore, programmers are in high demand. In Silicon Valley, companies are poaching employees from each other because the demand highly outgrew “tech talent” there.

Should I go for code bootcamp?

Bootcamp is an intensive few-weeks coding course. It worked for some of Chuck’s friends, but he knew that it would be a bad choice for him. He was always a self-learner and he despised the fact that in a group setting you need to go as slow as a dumbest person in the class or sometimes he needed more time but the group needed to push forward.

One advantage of coding bootcamp is discipline and accountability. The are in charge and they motivate and keep the score. In Poland, Coderslab appealed to him and he wasn’t girly enough for girlsjs, but he wanted to learn on his own terms.

Crossing the Treshold


A friend recommended to Chuck. It was created by Facebook and few other companies as an effort to teach kids how to code. Chuck played with few lessons and decided he felt confident enough to try something more serious.

The road of trials


What programming language should I learn?

When he started asking this seemingly innocent question, clearly he had no idea what he  was getting into. He didn’t mean to question anybody’s religious beliefs, but every time he brought the subject up, he got a different, strong opinion.

Chuck decided to listen to Artur’s advice and learn JavaScript. Following arguments convinced him:

  • JavaScript is one of the few languages that can be used in many layers of application. That meant that he would be able to switch positions without acquiring new language,
  • With React Native and other approaches it is now possible to also write mobile apps in JavaScript. If he decided to, he could write his own apps!,
  • JavaScript ecosystem is still growing rapidly. The demand will only grow.

So he started taking advantage of the amazing free material available on the web:

He also heard good things about a comprehensive free “How to be a programmer” guide.

The inmost cave

Contribute! Show off!


Chuck decided to call one of his friends who was responsible for hiring in a huge company.

  • “Listen”, asked Chuck, “If you are not looking at diplomas, how DO you know who to hire?”
  • In many companies it boils down to something called “technical interview”. Honestly, it’s exam-like situation, where we ask technical questions, ask you to solve some problems and generally grade you
  • Is this a reliable process?
  • No, it’s very sloppy and a bit random.
  • Ok, but how can I prepare?
  • I recommend Cracking Code Interview. These are hard and this books is really all you need to get into Google or Microsoft. But in many companies it’s MUCH easier. Usually it’s a few random questions related to specific programming language.
  • Is there something else you would recommend?
  • Open Source projects! It’s an easy way to get experience and make your CV stand out.
  • How do i start with that?
  • Start with Contributing to GitHub. There are plenty of projects that would appreciate help. You will learn  A LOT! Pro tip: Best way is to try to set up the project and start by fixing the “README” files. If you had to overcome some obstacle – fix the readme’s before the code. The maintainers of the project will appreciate your help and it will count as contribution. Also check out this guide on starting your Open Source contributions
  • Thanks for the chat!

The supreme ordeal

How do I get motivation?

IMG_4922 (1)

At this point Chuck felt a bit overwhelmed by possibilities and work to be done. Fortunately, one of his friends had a masters degree in psychology, so he asked him how to find a drive and strength to push forward.

His friend responded:

I have learned more about self-motivation from “Awaken the giant within” by Tony Robbins than during 5 years of psychology.

The book was a splendid recommendation. Chuck never felt so driven to get this done!


How much will I earn? How to find a job?


Chuck started asking himself what he should learn in order to get a job. What are the requirements? He heard it’s much better to just look for the offer in specific programming language he knew, so he can focus on improving his skills before he starts learning more.

The Road Back

I want to work remotely, like this Artur person!

What is this remote work? How come Artur is writing posts from all over the globe? Chuck managed to call Artur and ask how to get remote work

“Chuck, listen: there are some fully-distributed companies, but they are only functioning because people there are self-driven. It’s hard to control people when they are not in the office, so we need to be very careful in hiring. Almost always they require prior experience and I highly recommend first starting in some other company”


What’s next?

At the beginning of his programming career, Chuck decided to go for big / medium company. He heard, that he definitely should not join “a cool startup of his friend”. It could be bad for him and the startup.

  • Big company has processes and resources to teach more basics
  • His shortcomings will have little impact on the final result
  • There will be more “newbies”, so he wont feel like the only one without 10+ years of experience
  • There will be plenty patterns / good practices to absorb
  • In a big company it’s much easier to know what he doesn’t know

Chuck got a cool job at Samsung. He decided that he will learn constantly in his new job and after 2 years of corporate experience, he will try to step up the corporate ladder or get a better position somewhere else. Changing job in tech every ~3 years is considered normal.

Be smart, be like Chuck. Be a programmer. It’s awesome.


Why are these header titles so weird?

Other stuff I do

These are the apps I am currently developing. Subscribe for lessons learned while developing: