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svg with animate is not useful

See original GitHub issue

I have a svg file some code like: <circle transform="translate(8 0)" cx="0" cy="16" r="10" fill="#fff"> <animate attributeName="r" values="0; 4; 0; 0" dur="1.2s" repeatCount="indefinite" begin="0" keytimes="0;0.2;0.7;1" keySplines="0.2 0.2 0.4 0.8;0.2 0.6 0.4 0.8;0.2 0.6 0.4 0.8" calcMode="spline" /> </circle> but animate is not active

Issue Analytics

State:
Created 4 years ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

msandcommented, Aug 10, 2019

A bit refactored to make it more reusable:

import * as React from 'react';
import { Animated, Easing } from 'react-native';
import { Svg, Circle } from 'react-native-svg';
const AnimatedCircle = Animated.createAnimatedComponent(Circle);

function animateSpline({
  values,
  dur,
  repeatCount,
  begin,
  keyTimes,
  keySplines,
}) {
  const duration = dur * 1000;
  const t = new Animated.Value(keyTimes[0]);
  const splines = keySplines.map((spline, i) => {
    const [x1, y1, x2, y2] = spline;
    const fromValue = keyTimes[i];
    const toValue = keyTimes[i + 1];
    return Animated.timing(t, {
      toValue,
      delay: i == 0 ? begin : 0,
      duration: duration * (toValue - fromValue),
      easing: Easing.bezier(x1, y1, x2, y2),
      useNativeDriver: true,
    });
  });
  const iterations = repeatCount === 'indefinite' ? -1 : +repeatCount;
  const animation = Animated.loop(Animated.sequence(splines), { iterations });
  const value = t.interpolate({
    inputRange: keyTimes,
    outputRange: values,
  });
  return { t, animation, value };
}

export default () => {
  /*
    <circle cx="16" cy="16" r="16">
      <animate 
        attributeName="r" 
        values="0; 4; 0; 0" 
        dur="1.2s" 
        repeatCount="indefinite" 
        begin="0" 
        keytimes="0;0.2;0.7;1" 
        keySplines="0.2 0.2 0.4 0.8;0.2 0.6 0.4 0.8;0.2 0.6 0.4 0.8" 
        calcMode="spline" />
    </circle>
  */
  const { animation, value } = animateSpline({
    values: [0, 4, 0, 0],
    dur: 1.2,
    repeatCount: 'indefinite',
    begin: 0,
    keyTimes: [0, 0.2, 0.7, 1],
    keySplines: [
      [0.2, 0.2, 0.4, 0.8],
      [0.2, 0.6, 0.4, 0.8],
      [0.2, 0.6, 0.4, 0.8],
    ],
  });
  animation.start();
  return (
    <Svg width="100%" height="100%" viewBox="0 0 32 32">
      <AnimatedCircle cx="16" cy="16" r={value} />
    </Svg>
  );
};

1reaction

msandcommented, Aug 10, 2019

Couldn’t help myself 😄 https://snack.expo.io/@msand/animated-svg-with-bezier-spline-calcmode

import * as React from 'react';
import { Animated, Easing } from 'react-native';
import { Svg, Circle } from 'react-native-svg';
const AnimatedCircle = Animated.createAnimatedComponent(Circle);
/*
  <circle cx="16" cy="16" r="16">
    <animate 
      attributeName="r" 
      values="0; 4; 0; 0" 
      dur="1.2s" 
      repeatCount="indefinite" 
      begin="0" 
      keytimes="0;0.2;0.7;1" 
      keySplines="0.2 0.2 0.4 0.8;0.2 0.6 0.4 0.8;0.2 0.6 0.4 0.8" 
      calcMode="spline" />
  </circle>
*/
const values = [0, 4, 0, 0];
const dur = 1.2 * 1000;
const keyTimes = [0, 0.2, 0.7, 1];
const keySplines = [
  [0.2, 0.2, 0.4, 0.8],
  [0.2, 0.6, 0.4, 0.8],
  [0.2, 0.6, 0.4, 0.8],
];
export default () => {
  const t = new Animated.Value(keyTimes[0]);
  const splines = keySplines.map((spline, i) => {
    const [x1, y1, x2, y2] = spline;
    const fromValue = keyTimes[i];
    const toValue = keyTimes[i + 1];
    return Animated.timing(t, {
      toValue,
      duration: dur * (toValue - fromValue),
      easing: Easing.bezier(x1, y1, x2, y2),
      useNativeDriver: true,
    });
  });
  Animated.loop(Animated.sequence(splines)).start();
  return (
    <Svg width="100%" height="100%" viewBox="0 0 32 32">
      <AnimatedCircle
        cx="16"
        cy="16"
        r={t.interpolate({
          inputRange: keyTimes,
          outputRange: values,
        })}
      />
    </Svg>
  );
};