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API Reference

Dimensions

import { Dimensions } from 'react-native';
You can get the application window's width and height using the following code:
const windowWidth = Dimensions.get('window').width;
const windowHeight = Dimensions.get('window').height;
Although dimensions are available immediately, they may change (e.g due to device rotation, foldable devices etc) so any rendering logic or styles that depend on these constants should try to call this function on every render, rather than caching the value (for example, using inline styles rather than setting a value in a StyleSheet).
If you are targeting foldable devices or devices which can change the screen size or app window size, you can use the event listener available in the Dimensions module as shown in the below example.

Example

import React, { useState, useEffect } from 'react';
import { View, StyleSheet, Text, Dimensions } from 'react-native';

const window = Dimensions.get('window');
const screen = Dimensions.get('screen');

const App = () => {
  const [dimensions, setDimensions] = useState({ window, screen });

  useEffect(() => {
    const subscription = Dimensions.addEventListener('change', ({ window, screen }) => {
      setDimensions({ window, screen });
    });
    return () => subscription?.remove();
  });

  return (
    <View style={styles.container}>
      <Text style={styles.header}>Window Dimensions</Text>
      {Object.entries(dimensions.window).map(([key, value]) => (
        <Text>
          {key} - {value}
        </Text>
      ))}
      <Text style={styles.header}>Screen Dimensions</Text>
      {Object.entries(dimensions.screen).map(([key, value]) => (
        <Text>
          {key} - {value}
        </Text>
      ))}
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  header: {
    fontSize: 16,
    marginVertical: 10,
  },
});

export default App;

static addEventListener(type, handler)
Add an event handler. Supported events:
  • change: Fires when a property within the Dimensions object changes. The argument to the event handler is a DimensionsValue type object.

static get(dim)
Initial dimensions are set before runApplication is called so they should be available before any other require's are run, but may be updated later.
Example: const {height, width} = Dimensions.get('window');
Parameters:
NameTypeDescription
dim (Required)stringName of dimension as defined when calling set. Returns value for the dimension.
For Android the window dimension will exclude the size used by the status bar (if not translucent) and bottom navigation bar

static removeEventListener(type, handler)
Deprecated. Use the remove() method on the event subscription returned by addEventListener().

static set(dims)
This should only be called from native code by sending the didUpdateDimensions event.
Parameters:
NameTypeDescription
dims RequiredobjectString-keyed object of dimensions to set.

Properties:
NameTypeDescription
windowDisplayMetricsSize of the visible Application window.
screenDisplayMetricsSize of the device's screen.

Type
object
Properties:
NameType
widthnumber
heightnumber
scalenumber
fontScalenumber