Get size on fast image?

Is it possible to get the size of a fast image the same way to get size via React Native’s Image.getSize()?

[NoMaxLand]

@bemaverick it work from version 4.0.8 for me, maybe you need an update ?

@nica0012 You should use state to reload component who display your FastImage :

e.g :

import React, { Component } from "react";
import { Dimensions } from "react-native";
import FastImage from "react-native-fast-image";

const { width } = Dimensions.get("window");

export default class YourFastImage extends Component {
  constructor(props) {
    super(props);
    this.state = {
      calcImgHeight: 0,
    };
  }
  render() {
    const { calcImgHeight } = this.state;
    return (
      <FastImage
        style={{ width: width, height: calcImgHeight }}
        source={{
          uri: "https://unsplash.it/400/400?image=1",
        }}
        resizeMode={FastImage.resizeMode.contain}
        onLoad={evt =>
          this.setState({
            calcImgHeight:
              evt.nativeEvent.height / evt.nativeEvent.width * width, // By this, you keep the image ratio
          })}
      />
    );
  }
}

[woodpav]

@DylanVann I think an API involving a static FastImage.getSize or a callback on FastImage.preload would be useful.

My usecase is using FastImage inside of react-native-image-zoom. To use the onLoad callback I would have to use a wrapping component that doesnt render the ImageZoom component until the onLoad callback fires. This means I have to rerender the FastImage component after I get the image size. Here’s my current solution using Image.getSize.

https://gist.github.com/woodpav/1707e59feff35502ab9801bf84447c16