react-native-size-matters

What is react-native-size-matters?

The react-native-size-matters package provides utility functions to handle scaling of sizes in a React Native application. It helps in making the app responsive across different screen sizes and resolutions.

What are react-native-size-matters's main functionalities?

Scaling Sizes

This feature allows you to scale sizes based on the device's screen size. The `scale`, `verticalScale`, and `moderateScale` functions help in scaling width, height, and other dimensions respectively. The `ScaledSheet` utility allows you to define styles with scaling directly in the stylesheet.

import { ScaledSheet, moderateScale, verticalScale, scale } from 'react-native-size-matters';

const styles = ScaledSheet.create({
  container: {
    width: '100@s', // scales the width
    height: '50@vs', // scales the height vertically
    padding: '10@ms', // scales the padding moderately
  },
});

const scaledWidth = scale(100);
const scaledHeight = verticalScale(50);
const scaledPadding = moderateScale(10);

ScaledSheet

The `ScaledSheet` utility allows you to create stylesheets where you can use scaling directly in the style definitions. This makes it easier to maintain and apply consistent scaling across your application.

import { ScaledSheet } from 'react-native-size-matters';

const styles = ScaledSheet.create({
  container: {
    width: '100@s',
    height: '50@vs',
    padding: '10@ms',
  },
  text: {
    fontSize: '14@ms',
  },
});

Other packages similar to react-native-size-matters

react-native-responsive-screen

The react-native-responsive-screen package provides utility functions to make your React Native app responsive. It offers functions like `widthPercentageToDP` and `heightPercentageToDP` to convert percentage-based dimensions to device pixels. Compared to react-native-size-matters, it focuses more on percentage-based scaling rather than fixed scaling values.

react-native-dimension

The react-native-dimension package provides a simple way to handle responsive design in React Native. It offers functions like `getWidth` and `getHeight` to get dimensions based on the device's screen size. While it provides similar functionality to react-native-size-matters, it is less feature-rich and does not offer moderate scaling or a scaled stylesheet utility.

README

react-native-size-matters

A React-Native utility belt for scaling the size your apps UI across different sized devices.

Installation

npm install --save react-native-size-matters
//or:
yarn add react-native-size-matters

Motivation

When developing with react-native, you need to manually adjust your app to look great on variety of different screen sizes. That's a tedious job.
react-native-size-matters provides some simple tooling to make your scaling a whole lot easier.
The idea is to develop once on a standard ~5" screen mobile device and then simply apply the provided utils.
📖 You can read more about what led to this library on my blog post, that can be found in this repo or at Soluto Engineering Blog.

Api

Scaling Functions

import { scale, verticalScale, moderateScale } from 'react-native-size-matters';

const Component = props =>
    <View style={{
        width: scale(30),
        height: verticalScale(50),
        padding: moderateScale(5)
    }}/>;

• scale(size: number)
  Will return linear scaled result of the provided size, based on your device's screen width.

• verticalScale(size: number)
  Will return linear scaled result of the provided size, based on your device's screen height.

• moderateScale(size: number, factor?: number)
  Sometimes you don't want to scale everything in a linear manner, that's where moderate scale comes in.
  The cool thing about it is that you can control the resize factor (default is 0.5).
  If normal scale will increase your size by +2X, moderateScale will only increase it by +X, for example:
  ➡️ scale(10) = 20
  ➡️ moderateScale(10) = 15
  ➡️ moderateScale(10, 0.1) = 11

ScaledSheet

import { ScaledSheet } from 'react-native-size-matters';

const styles = ScaledSheet.create(stylesObject)

ScaleSheet will take the same stylesObject a regular StyleSheet will take, plus a special (optional) annotation that will automatically apply the scale functions for you:

• <size>@s - will apply scale function on size.
• <size>@vs - will apply verticalScale function on size.
• <size>@ms - will apply moderateScale function with resize factor of 0.5 on size.
• <size>@ms<factor> - will apply moderateScale function with resize factor of factor on size.

Example:

import { ScaledSheet } from 'react-native-size-matters';

const styles = ScaledSheet.create({
    container: {
        width: '100@s', // = scale(100)
        height: '200@vs', // = verticalScale(200)
        margin: 5
    },
    row: {
        padding: '10@ms0.3', // = moderateScale(10, 0.3)
        height: '50@ms' // = moderateScale(50)
    }
});

Changing the Default Guideline Sizes

In the ever changing mobile devices world screen sizes change a lot.
This lib uses 350dp x 680dp as guideline sizes, but if you (or your designer) prefer using different sizes it's possible.

To do so, first you'd need to setup react-native-dotenv.
After setting it up and creating .env file, add the following env params to it:

SIZE_MATTERS_BASE_WIDTH=<custom-width>
SIZE_MATTERS_BASE_HEIGHT=<custom-height>

Next and final step, you should change all your imports to react-native-size-matters/extend, for instance:

import { ScaledSheet, moderateScale } from `react-native-size-matters/extend`;

Examples

You can clone the expo-example-app from this repo, run npm install and npm start and scan the presented QR code in the Expo app on your preferred device.
The app has a on/off switch for using react-native-size-matters, so you can test yourself how the app will look with and without scaling.
It is expected to look good on every device you want - iOS or Android, phone or tablet, basically anything (please let me know if not).
There are also some attached screenshots in the repo if you don't feel like cloning.