小编Pik*_*urd的帖子

React-native引入了新的AnimatedAPI,我想制作一个循环动画,比如泡沫缩放,然后按比例缩小并重复这个进度.

但是我无法弄明白.我试过写下面的代码

class TestProject extends React.Component {

  constructor(): void {
    super();
    this.state = {
      bounceValue: new Animated.Value(0),
      v: 1,
    };
  }

  componentDidMount() {
    this.state.bounceValue.setValue(1.5);

    let animation = Animated.timing(this.state.bounceValue, {
      toValue: this.state.v,
    });

    setInterval(() => {
      animation.stop();

      if (this.state.flag) {
        this.state.v = 0.5;
        this.state.bounceValue.setValue(0.5);
      }
      else {
        this.state.v = 1.5;
        this.state.bounceValue.setValue(1.5);
      }

      animation.start();
    }, 5000);

  }

  render(): ReactElement {
    return (
      <View style={styles.imageContainer}>
        <Image
          style={styles.image}
          source={{uri: 'http://image142-c.poco.cn/best_pocoers/20130517/91062013051716553599334223.jpg'}}
        />
        <Animated.Text
          style={[
            styles.test,
            {transform: [
              {scale: this.state.bounceValue},
            ],}
          ]
          }>
          haha …

操作系统:MacOSX 10.7.1来自brew的GHC和Haskell平台.

   GHCi, version 7.0.4: http://www.haskell.org/ghc/  :? for help
    Loading package ghc-prim ... linking ... done.
    Loading package integer-gmp ... linking ... done.
    Loading package base ... linking ... done.
    Loading package ffi-1.0 ... linking ... done.
    Prelude> :m +Text.Regex.Posix
    Prelude Text.Regex.Posix> "foo" =~ "o" :: [String]

    <interactive>:1:7:
        No instance for (RegexContext Regex [Char] [String])
          arising from a use of `=~'
        Possible fix:
          add an instance declaration for
          (RegexContext Regex [Char] [String])
        In the expression: "foo" =~ "o" :: [String] …