与Expo配合使用的React Native图像裁剪工具

Question

Is anyone aware of an image cropping tool for React Native that works within the Expo setup. The very popular react-native-image-crop-picker doesn't. Is there any alternatives? I can't seem to find any.

Answer 1

You may use aspect 4:3, 16:9, 1:1 and so on

import { ImagePicker } from 'expo';

are you getting photo from gallery?

const photo = await ImagePicker.launchImageLibraryAsync({
   allowsEditing: true,
   aspect: [4, 3],
});

Answer 2

You can download the image with Expo#FileSystem and then crop the cached image with Expo#ImageManipulator Here is a sample

/*
 * @param link {string} URI of the image on the server
 * @param name {string} Name of the image with extension
 */
_downloadAndCrop = (link, name, cropSize = { width: 200, height: 200 }) => {
    FileSystem.downloadAsync(
       link,
       name
   )
   .then(({ uri }) => {
       console.log('Finished downloading to ', uri);
       //Your new cropped image
       const cropImage = ImageManipulator.manipulate(uri, [
                             crop: { 
                                 originX: 0, 
                                 originY: 0, 
                                 width: cropSize.width, 
                                 height: cropSize.height 
                             }
                         }], {});
   })
   .catch(error => {
       console.error(error);
   });
}