Simple Recipe to Build a Theme App in React Native

Recently, I have been working on a React Native application that demands a changeable theme based on the user selection. I wanted to do this in a simplest way possible. I have so far avoided any React Native UI toolkit such as NativeBase or React Native Elements. In the article below, I am going to share with you all about this simple recipe. This is what we are building. By the end of this article you will have a similar looking React Native project. Requirements You can either clone the application to see how it works from this Github repo here to see everything working properly. Or you can follow the article step by step. It is up to you. To start, generate a react native app using a generator of your choice. We have to choices: react-native cli expo-cli/CRNA I will use expo-cli for the demo purposes but you can use CRNA(Create-React-Native-Project) if you want. We need to the following dependencies to be installed in our project before we start. redux redux-logger(optional, it will be better for you to debug in case anything goes wrong) react-navigation react-native-vector-icons (only install if you are using react-native-cli) Getting Started: Navigation We need only two screen for the demonstration. I am going to call them and . Both are right now contain only boilerplate code. It is good for them to be dumb until we connect them using . Create a new file called and import both the components. Home.js Theme.js react-navigation navigation.js is the replacement to in version 2+. Notice that, we are not passing a header to the Home Screen. createStackNavigator StackNavigator react-navigation Creating a Store using Redux Next step is to build a redux store that will make use of an action, action creator and reducer to change theme in our application. In put the following code. actions.js We only have one action and changes the theme color of the app. Now the reducer: Notice that we are setting the primary color in the initial state as the hex value. You can also retrieve it from a configuration file or constants file in your application. We are also exporting the file which contains three different hex code values that define different color schemes. colors.js Lastly, create the store and it to for the application components to use it. App.js Inside file we connect our Redux store to manage the state as well as navigation. App.js You might be wondering why the heck use a Redux Store for such a small application. Well, all I am trying to demonstrate is a pragmatic approach to build a them-able application using React Native and Redux. It is your choice to manage the state. Finalising the App The last components of our React Native application from where the action happens are and . Home.js Theme.js By pressing the settings icon, we can navigate to the Themes screen to change background color of the Home screen. We are also passing the title of the Theme Screen here. The magic of changing the color is happening in at this line: Home.js We are receiving the from the props. The file will be changing the value of this prop on selecting a viable option. Take a look below. primaryColor Theme.js In above, handles the dispatching of the only action we defined in . At last, we have our app working. handleThemeChange actions.js You can find the complete code in this Github repository.👇 _⚛️ + 📱. Contribute to amandeepmittal/30daysofReactNative development by creating an account on GitHub._github.com amandeepmittal/30daysofReactNative My name is . I am a developer who builds and consults on Node.js related web apps and ❤️s React Native. This is my and . Aman Mittal website Twitter If you are unfamiliar on how to use/integrate Redux in a React Native and want learn more about it, you should check the article below. _Redux is an important part of the React Native ecosystem. If your world revolves around JavaScript, you’ve probably…_medium.freecodecamp.org How to integrate Redux into your application with React Native and Expo To get notified about my next React Native article, please use this form to signup to my personal newsletter.