react-native-blur/README.md

@react-native-community/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

1. Install the library using either Yarn:

yarn add @react-native-community/blur

or npm:

npm install --save @react-native-community/blur

2. Link your native dependencies:

react-native link @react-native-community/blur

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

android {
    // make sure to use 23.0.3 or greater
    buildToolsVersion '23.0.3'

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

4. (Android only, optional) If you've defined project-wide properties (recommended) in your root build.gradle, this library will detect the presence of the following properties:

buildscript {...}
allprojects {...}

/**
  + Project-wide Gradle configuration properties
  */
ext {
    compileSdkVersion   = 27
    targetSdkVersion    = 27
    buildToolsVersion   = "27.0.3"
}

5. Include the library in your code:

import { BlurView, VibrancyView } from "@react-native-community/blur";

6. Compile and have fun!

BlurView

Properties:

• blurType (String)
  • xlight - extra light blur type
  • light - light blur type
  • dark - dark blur type
  • extraDark - extra dark blur type (tvOS only)
  • regular - regular blur type (iOS 10+ and tvOS only)
  • prominent - prominent blur type (iOS 10+ and tvOS only)
• 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-community/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}>
        <Text>Hi, I am some unblurred text</Text>
        <BlurView
          style={styles.absolute}
          viewRef={this.state.viewRef}
          blurType="light"
          blurAmount={10}
        />
        <Image
          ref={img => {
            this.backgroundImage = img;
          }}
          source={{ uri }}
          style={styles.absolute}
          onLoadEnd={this.imageLoaded.bind(this)}
        />
      </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-community/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 example

cd react-native-blur/example

3. Install dependencies

npm install

4. Run the apps:

Run the iOS app

react-native run-ios

Run the tvOS app

type:

react-native run-ios

react-native link don’t works properly with the tvOS target so we need to add the library manually.

First select your project in Xcode.

After that, select the tvOS target of your application and select « General » tab

Scroll to « Linked Frameworks and Libraries » and tap on the + button

Select RNBlur-tvOS

That’s all, you can use react-native-blur for your tvOS application

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 on twitter or create an issue