react-native/RNTester/js/AnimatedExample.js

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @format
 * @flow
 */

'use strict';

var React = require('react');
var ReactNative = require('react-native');
var {Animated, Easing, StyleSheet, Text, View} = ReactNative;
var RNTesterButton = require('./RNTesterButton');

exports.framework = 'React';
exports.title = 'Animated - Examples';
exports.description =
  'Animated provides a powerful ' +
  'and easy-to-use API for building modern, ' +
  'interactive user experiences.';

exports.examples = [
  {
    title: 'FadeInView',
    description:
      'Uses a simple timing animation to ' +
      'bring opacity from 0 to 1 when the component ' +
      'mounts.',
    render: function() {
      class FadeInView extends React.Component<$FlowFixMeProps, any> {
        constructor(props) {
          super(props);
          this.state = {
            fadeAnim: new Animated.Value(0), // opacity 0
          };
        }
        componentDidMount() {
          Animated.timing(
            // Uses easing functions
            this.state.fadeAnim, // The value to drive
            {
              toValue: 1, // Target
              duration: 2000, // Configuration
            },
          ).start(); // Don't forget start!
        }
        render() {
          return (
            <Animated.View // Special animatable View
              style={{
                opacity: this.state.fadeAnim, // Binds
              }}>
              {this.props.children}
            </Animated.View>
          );
        }
      }
      class FadeInExample extends React.Component<$FlowFixMeProps, any> {
        constructor(props) {
          super(props);
          this.state = {
            show: true,
          };
        }
        render() {
          return (
            <View>
              <RNTesterButton
                onPress={() => {
                  this.setState(state => ({show: !state.show}));
                }}>
                Press to {this.state.show ? 'Hide' : 'Show'}
              </RNTesterButton>
              {this.state.show && (
                <FadeInView>
                  <View style={styles.content}>
                    <Text>FadeInView</Text>
                  </View>
                </FadeInView>
              )}
            </View>
          );
        }
      }
      return <FadeInExample />;
    },
  },
  {
    title: 'Transform Bounce',
    description:
      'One `Animated.Value` is driven by a ' +
      'spring with custom constants and mapped to an ' +
      'ordered set of transforms.  Each transform has ' +
      'an interpolation to convert the value into the ' +
      'right range and units.',
    render: function() {
      this.anim = this.anim || new Animated.Value(0);
      return (
        <View>
          <RNTesterButton
            onPress={() => {
              Animated.spring(this.anim, {
                toValue: 0, // Returns to the start
                velocity: 3, // Velocity makes it move
                tension: -10, // Slow
                friction: 1, // Oscillate a lot
              }).start();
            }}>
            Press to Fling it!
          </RNTesterButton>
          <Animated.View
            style={[
              styles.content,
              {
                transform: [
                  // Array order matters
                  {
                    scale: this.anim.interpolate({
                      inputRange: [0, 1],
                      outputRange: [1, 4],
                    }),
                  },
                  {
                    translateX: this.anim.interpolate({
                      inputRange: [0, 1],
                      outputRange: [0, 500],
                    }),
                  },
                  {
                    rotate: this.anim.interpolate({
                      inputRange: [0, 1],
                      outputRange: [
                        '0deg',
                        '360deg', // 'deg' or 'rad'
                      ],
                    }),
                  },
                ],
              },
            ]}>
            <Text>Transforms!</Text>
          </Animated.View>
        </View>
      );
    },
  },
  {
    title: 'Composite Animations with Easing',
    description:
      'Sequence, parallel, delay, and ' +
      'stagger with different easing functions.',
    render: function() {
      this.anims = this.anims || [1, 2, 3].map(() => new Animated.Value(0));
      return (
        <View>
          <RNTesterButton
            onPress={() => {
              var timing = Animated.timing;
              Animated.sequence([
                // One after the other
                timing(this.anims[0], {
                  toValue: 200,
                  easing: Easing.linear,
                }),
                Animated.delay(400), // Use with sequence
                timing(this.anims[0], {
                  toValue: 0,
                  easing: Easing.elastic(2), // Springy
                }),
                Animated.delay(400),
                Animated.stagger(
                  200,
                  this.anims
                    .map(anim => timing(anim, {toValue: 200}))
                    .concat(this.anims.map(anim => timing(anim, {toValue: 0}))),
                ),
                Animated.delay(400),
                Animated.parallel(
                  [
                    Easing.inOut(Easing.quad), // Symmetric
                    Easing.back(1.5), // Goes backwards first
                    Easing.ease, // Default bezier
                  ].map((easing, ii) =>
                    timing(this.anims[ii], {
                      toValue: 320,
                      easing,
                      duration: 3000,
                    }),
                  ),
                ),
                Animated.delay(400),
                Animated.stagger(
                  200,
                  this.anims.map(anim =>
                    timing(anim, {
                      toValue: 0,
                      easing: Easing.bounce, // Like a ball
                      duration: 2000,
                    }),
                  ),
                ),
              ]).start();
            }}>
            Press to Animate
          </RNTesterButton>
          {['Composite', 'Easing', 'Animations!'].map((text, ii) => (
            <Animated.View
              key={text}
              style={[
                styles.content,
                {
                  left: this.anims[ii],
                },
              ]}>
              <Text>{text}</Text>
            </Animated.View>
          ))}
        </View>
      );
    },
  },
  {
    title: 'Continuous Interactions',
    description:
      'Gesture events, chaining, 2D ' +
      'values, interrupting and transitioning ' +
      'animations, etc.',
    render: () => <Text>Checkout the Gratuitous Animation App!</Text>,
  },
];

var styles = StyleSheet.create({
  content: {
    backgroundColor: 'deepskyblue',
    borderWidth: 1,
    borderColor: 'dodgerblue',
    padding: 20,
    margin: 20,
    borderRadius: 10,
    alignItems: 'center',
  },
});