请教，关于图片轮播预览手势缩放功能实现 about zqc-app-demo HOT 3 CLOSED

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  render() {
    let {navigator, screen, setScreenState} = this.props;
    let {files, currentIndex, navBarHidden} = screen[this.screenId];

    navigator.toggleNavBar({'to': (navBarHidden ? 'hidden' : 'shown')});

    return (
      <components.Layout screenId={this.screenId} containerStyle={{backgroundColor: 'black'}}>
        <components.ActionSheet ref={ref => this.actionSheet = ref} />
        <Gallery
          images={files.map(v => helpers.fileImageSource(v, 'huge').uri)}
          initialPage={currentIndex}
          pageMargin={5}
          onPageSelected={index => setScreenState(this.screenId, {currentIndex: index})}
          onSingleTapConfirmed={() => setScreenState(this.screenId, {navBarHidden: !navBarHidden})}
        />
      </components.Layout>
    );
  }
}
...