React Native Blur

A component for UIVisualEffectView's blur and vibrancy effect on iOS, and 500px-android-blur on Android.

Content

• Installation
• BlurView
• VibrancyView
• Example React Native app
• Questions?

Installation

NOTE: Latest version of the package is available in npm as react-native-blur@3.0.0-alpha

1. Install package via npm:

npm install react-native-blur

2. Link your native dependencies:

react-native link react-native-blur

3. (Android only) Add the following to android/app/build.gradle

android {
    // ...
    defaultConfig {
        // Add these lines below the existing config
        renderscriptTargetApi 23
        renderscriptSupportModeEnabled true
    }
}

4. Include the library in your code:

import { BlurView, VibrancyView } from 'react-native-blur';

// OR

const { BlurView, VibrancyView } = require('react-native-blur');

5. Compile and have fun!

BlurView

Properties:

• blurType (String)
  • xlight - extra light blur type
  • light - light blur type
  • dark - dark blur type
• blurAmount (Default: 10, Number)
  • 0-100 - Adjusts blur intensity

Note: The maximum blurAmount on Android is 32, so higher values will be clamped to 32.

Complete usage example that works on iOS and Android:

import React, { Component } from 'react';
import { View, Image, Text, findNodeHandle, StyleSheet } from 'react-native';
import { BlurView } from 'react-native-blur';

export default class Menu extends Component {
  constructor(props) {
    super(props);
    this.state = { viewRef: null };
  }

  imageLoaded() {
    this.setState({ viewRef: findNodeHandle(this.backgroundImage) });
  }

  render() {
    return (
      <View style={styles.container}>
        <Image
          ref={(img) => { this.backgroundImage = img; }}
          source={{uri}}
          style={styles.absolute}
          onLoadEnd={this.imageLoaded.bind(this)}
        />
        <BlurView
          style={styles.absolute}
          viewRef={this.state.viewRef}
          blurType="light"
          blurAmount={10}
        />
        <Text>Hi, I am some unblurred text</Text>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    justifyContent: 'center',
    alignItems: 'center',
  },
  absolute: {
    position: "absolute",
    top: 0, left: 0, bottom: 0, right: 0,
  },
});

In this example, the Image component will be blurred, because the BlurView in positioned on top. But the Text will stay unblurred.

Note that viewRef is only required if you need to support Android. See the Android section for more details.

VibrancyView

Uses the same properties as BlurView (blurType and blurAmount).

The vibrancy effect lets the content underneath a blurred view show through more vibrantly

(Note: VibrancyView is only supported on iOS. Also note that the VibrancyView must contain nested views.)

import { VibrancyView } from 'react-native-blur';

export default class Menu extends Component {
  render() {
    return (
      <Image source={{uri}} style={styles.absolute}>
        <VibrancyView blurType="light" style={styles.flex}>
          <Text>Hi, I am some vibrant text.</Text>
        </VibrancyView>
      </Image>
    );
  }
}

Android

Android uses the 500px-android-blur library, which works by blurring a referenced view. This means that you must wait until the view you want to blur is rendered. You then use findNodeHandle to get a reference to that view, and pass that reference to the BlurView as the viewRef prop. Take a look at the BlurView example to see how it works.

The Android library introduces some limitations:

• BlurView cannot be a child of the view that is being blurred (this would cause an infinite loop)
• BlurView cannot contain any child components.

If you only need to support iOS, then you can safely ignore these limitations.

In addition to blurType and blurAmount, Android has some extra props that can be used to override the default behavior (or configure Android-specific behavior):

• blurRadius (Number - between 0 and 25) - Manually adjust the blur radius. (Default: matches iOS blurAmount)
• downsampleFactor (Number - between 0 and 25) - Scales down the image before blurring (Default: matches iOS blurAmount)
• overlayColor (Color) - Set a custom overlay color (Default color based on iOS blurType)

Example React Native App

This project includes an example React Native app, which was used to make the GIF in this README. You can run the apps by following these steps:

1. Clone the repository

cd ~
git clone https://github.com/react-native-community/react-native-blur.git

2. cd to examples/Basic

cd react-native-blur/examples/Basic

3. Install dependencies

npm install

4. Run the apps:

Run the iOS app

react-native run-ios

Run the Android app

react-native run-android

Troubleshooting

On older instances of react-native, BlurView package does not get added into the MainActivity/MainApplication classes where you would see Warning: Native component for 'BlurView' does not exist in RN YellowBox or console.

To rectify this, you can add the BlurViewPackage manually in MainActivity/MainApplication classes

...
import com.cmcewen.blurview.BlurViewPackage;
...

public class MainApplication extends Application implements ReactApplication {
...
    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
          new BlurViewPackage()
      );
    }
...
}

Questions?

Feel free to contact me in twitter or create an issue