message: chore(ImagePreview): fix demo error
diff: @@ -408,10 +408,9 @@ export default createComponent({
  // @exposed-api
  swipeTo(index, options) {
  - if (!this.$refs.swipe) {
  - return;
  + if (this.$refs.swipe) {
  + this.$refs.swipe.swipeTo(index, options);
  }
  - this.$refs.swipe.swipeTo(+index, options);
  },
  },
  