{this.setState({uploadImgs: urls}) }}src={uploadImgs}/>” can be called to select and upload images."/> {this.setState({uploadImgs: urls}) }}src={uploadImgs}/>” can be called to select and upload images.">

Home  >  Article  >  Web Front-end  >  How to implement image selection in react

How to implement image selection in react

藏色散人
藏色散人Original
2023-01-19 14:21:401475browse

How to implement image selection in react: 1. Use import to introduce the "react-native-image-picker" plug-in; 2. Use "{this.setState({uploadImgs: urls})}}src ={uploadImgs}/>" can be called to select and upload images. ={6}onchange={urls>

How to implement image selection in react

The operating environment of this tutorial: Windows 10 system, react18.0.0 version, Dell G3 computer.

How to implement image selection in react?

React Native Qiniu Upload Local Image Selection

Reference:

react-native-image-crop-picker图片选择并裁减 //这个看需求使用
https://github.com/ivpusic/react-native-image-crop-picker
react-native-image-picker图片选择
https://github.com/react-native-image-picker/react-native-image-picker
react-native-qiniu
https://github.com/buhe/react-native-qiniu

I only want a multi-image upload function, so I will write it simply

Effect

How to implement image selection in react

Uploaded status

How to implement image selection in react

Uploading status

Step

1. Mobile phone picture and video selection function

Use react-native-image-picker plug-in

yarn add react-native-image-picker; ios requires pod install ;

import {launchCamera, launchImageLibrary, ImageLibraryOptions, PhotoQuality} from 'react-native-image-picker';
/**
 * 从相册选择图片;
 * sourceType: 'camera'  打开相机拍摄图片
**/
export async function chooseImage(options: {
  count?: number,
  quality?: PhotoQuality
  sourceType?: 'camera',  //默认'album'
} = {}) {
  return new Promise<any>(async(resolve, reject) => {
    const Opts: ImageLibraryOptions = {
      mediaType: &#39;photo&#39;,
      quality: options.quality || 1,
      selectionLimit: options.count || 1
    };
    const result = options.sourceType == &#39;camera&#39;? 
      await launchCamera(Opts) : 
      await launchImageLibrary(Opts);
    resolve(result)
  })
}
/**
 * 从相册选择视频;
 * sourceType: &#39;camera&#39;  打开相机拍摄视频
**/
export async function chooseVideo(options: {
  count?: number,
  quality?: &#39;low&#39; | &#39;high&#39;
  sourceType?: &#39;camera&#39;,  //默认&#39;album&#39;
} = {}) {
  return new Promise<any>(async(resolve, reject) => {
    const Opts: ImageLibraryOptions = {
      mediaType: &#39;video&#39;,
      videoQuality: options.quality,
      selectionLimit: options.count || 1
    };
    const result = options.sourceType == &#39;camera&#39;? 
      await launchCamera(Opts) : 
      await launchImageLibrary(Opts);
    resolve(result)
  })
}

2. Qiniu file upload function

class qiniuUpload {
  private UP_HOST = &#39;http://upload.qiniu.com&#39;;
  // private RS_HOST = &#39;http://rs.qbox.me&#39;;
  // private RSF_HOST = &#39;http://rsf.qbox.me&#39;;
  // private API_HOST = &#39;http://api.qiniu.com&#39;;
  public upload = async(uri:string, key:string, token:string) => {
    return new Promise<any>((resolve, reject) => {
      let formData = new FormData();
      formData.append(&#39;file&#39;, {uri: uri, type: &#39;application/octet-stream&#39;, name: key});
      formData.append(&#39;key&#39;, key);
      formData.append(&#39;token&#39;, token);
    
      let options:any = {
        body: formData,
        method: &#39;post&#39;,
      };
      fetch(this.UP_HOST, options).then((response) => {
        resolve(response)
      }).catch(error => {
        console.error(error)
        resolve(null)
      });  
    })
  }
   //...后面再加别的功能
}
const qiniu = new qiniuUpload();
export default qiniu;
import qiniu from &#39;@/modules/qiniu/index&#39;
...
  /**
   * 上传视频图片
   */
  uploadFile: async (filePath: string) => {
    const res = await createBaseClient(&#39;GET&#39;, &#39;/v1/file&#39;)();  //这是接口请求方法,用来拿后端的七牛token、key
    
    if( !res ) {
      return res;
    }
    const { key, token } = res;
    const fileSegments = filePath.split(&#39;.&#39;);
    const fileKey = key + &#39;.&#39; + fileSegments[fileSegments.length - 1];
    try {
      const result = await qiniu.upload(filePath, fileKey, token)
      if(result && result.ok) {
        return {
          url: ASSET_HOST + &#39;/&#39; + fileKey,  //ASSET_HOST是资源服务器域名前缀
        };
      }else {
        return null
      }
    } catch (error) {
      return null;
    }
  },
...

3. Multi-picture upload component encapsulation

(Base, Image, and ActionSheet are all encapsulated here, please see Situation adjustment)

import React from &#39;react&#39;
import {
  ViewStyle,
  StyleProp,
  ImageURISource,
  ActivityIndicator
} from &#39;react-native&#39;
import Base from &#39;@/components/Base&#39;;
import { Image, View, Text } from &#39;@/components&#39;;   //Image封装过的,所以有些属性不一样
import ActionSheet from "@/components/Feedback/ActionSheet";  //自己封装
import styles from &#39;./styleCss&#39;;  //样式就不放上来了
interface Props {
  type?: &#39;video&#39;
  src?: string[]
  count?: number
  btnPath?: ImageURISource
  style?: StyleProp<ViewStyle>
  itemStyle?: StyleProp<ViewStyle>
  itemWidth?: number
  itemHeight?: number  //默认正方形
  onChange?: (e) => void
}
interface State {
  imageUploading: boolean
  images: string[]
}
/**
 * 多图上传组件
 * * type?: &#39;video&#39;
 * * src?: string[]   //图片数据,可用于初始数据
 * * count?: number    //数量
 * * btnPath?: ImageURISource   //占位图
 * * itemStyle?: item样式,width, height单独设
 * * itemWidth?: number
 * * itemHeight?: number  //默认正方形
 * * onChange?: (e:string[]) => void
**/
export default class Uploader extends Base<Props, State> {
  public state: State = {
    imageUploading: false,
    images: []
  };
  public didMount() {
    this.initSrc(this.props.src)
  }
  public componentWillReceiveProps(nextProps){
    if(nextProps.hasOwnProperty(&#39;src&#39;) && !!nextProps.src){
      this.initSrc(nextProps.src)
    }
  }
  /**
   *初始化以及改动图片
  **/
  private initSrc = (srcProp:any) => {
    if(!this.isEqual(srcProp, this.state.images)) {
      this.setState({
        images: srcProp
      })
    }
  }
  
  public render() {
    const { style, btnPath, count, itemStyle, itemWidth, itemHeight, type } = this.props;
    const { imageUploading, images } = this.state;
    let countNumber = count? count: 1
    return (
      <React.Fragment>
        <View style={[styles.uploaderBox, style]}>
          {images.length > 0 && images.map((res, ind) => (
            <View style={[styles.item, itemStyle]} key={res}>
              <View style={styles.imgItem}>
                <Image
                  source={{uri: res}}
                  width={this.itemW}
                  height={this.itemH}
                  onPress={() => {
                    this.singleEditInd = ind;
                    this.handleShowActionSheet()
                  }}
                />
                <Text style={styles.del} onPress={this.handleDelete.bind(null, ind)}>删除</Text>
              </View>
            </View>
          ))}
          {images.length < countNumber  &&
            <View style={[styles.item, itemStyle]}> 
              {imageUploading? (
                <View style={[{
                  width: this.itemW,
                  height: this.itemH,
                }, styles.loading]}>
                  <ActivityIndicator size={this.itemW*0.4}></Loading>
                  <Text style={{
                    fontSize: 14,
                    color: &#39;#888&#39;,
                    marginTop: 5
                  }}>
                    上传中...
                  </Text>
                </View>
              ): (
                <View style={styles.btn}>
                  <Image
                    source={btnPath || this.assets.uploadIcon}
                    width={this.itemW}
                    height={this.itemH}
                    onPress={() => {
                      this.singleEditInd = undefined;
                      this.handleShowActionSheet()
                    }}
                  />
                </View>
              )}
              
            </View>
          }
          
        </View>
        <ActionSheet
          name="uploaderActionSheet"
          options={[{
            name: type == &#39;video&#39;? &#39;拍摄&#39;: &#39;拍照&#39;,
            onClick: () => {
              if(type == &#39;video&#39;) {
                this.handleChooseVideo(&#39;camera&#39;)
              }else if(this.singleEditInd !== undefined) {
                this.handleChooseSingle(&#39;camera&#39;)
              }else {
                this.handleChooseImage(&#39;camera&#39;)
              }
            }
          }, {
            name: &#39;相册&#39;,
            onClick: () => {
              if(type == &#39;video&#39;) {
                this.handleChooseVideo()
              }else if(this.singleEditInd !== undefined) {
                this.handleChooseSingle()
              }else {
                this.handleChooseImage()
              }
            }
          }]}
        ></ActionSheet>
      </React.Fragment>
    );
  }
  private get itemW() {
    return this.props.itemWidth || 92
  }
  private get itemH() {
    return this.props.itemHeight || this.itemW;
  }
  
  private isEqual = (firstValue, secondValue) => {
    /** 判断两个值(数组)是否相等 **/
    if (Array.isArray(firstValue)) {
      if (!Array.isArray(secondValue)) {
        return false;
      }
      if(firstValue.length != secondValue.length) {
        return false;
      }
      return firstValue.every((item, index) => {
        return item === secondValue[index];
      });
    }
    return firstValue === secondValue;
  }
  private handleShowActionSheet = () => {
    this.feedback.showFeedback(&#39;uploaderActionSheet&#39;);  //这是显示ActionSheet选择弹窗。。。
  }
  private handleChooseImage = async (sourceType?: &#39;camera&#39;) => {
    const { imageUploading, images } = this.state;
    const { count } = this.props
    if (imageUploading) {
      return;
    }
    let countNumber = count? count: 1
    const { assets } = await this.interface.chooseImage({  //上面封装的选择图片方法
      count: countNumber,
      sourceType: sourceType || undefined,
    });
    
    if(!assets) {
      return;
    }
    this.setState({
      imageUploading: true,
    });
    
    let request:any = []
    assets.map(res => {
      let req = this.apiClient.uploadFile(res.uri)   //上面封装的七牛上传方法
      request.push(req)
    })
    Promise.all(request).then(res => {
      let imgs:any = []
      res.map((e:any) => {
        if(e && e.url){
          imgs.push(e.url)
        }
      })
      imgs = [...images, ...imgs];
      this.setState({
        images: imgs.splice(0,countNumber),
        imageUploading: false,
      },
        this.handleChange
      );
    })
    
  }
  private singleEditInd?: number;  //修改单个时的索引值
  private handleChooseSingle = async(sourceType?: &#39;camera&#39;) => {
    let { imageUploading, images } = this.state;
    if (imageUploading) {
      return;
    }
    
    const { assets } = await this.interface.chooseImage({   //上面封装的选择图片方法
      count: 1,
      sourceType: sourceType || undefined,
    });
    if(!assets) {
      return;
    }
    this.setState({
      imageUploading: true,
    });
    const res = await this.apiClient.uploadFile(assets[0].uri)   //上面封装的七牛上传方法
    if(res && res.url && this.singleEditInd){
      images[this.singleEditInd] = res.url
    }
    this.setState({
      images: [...images],
      imageUploading: false,
    },
      this.handleChange
    );
    
  }
  private handleChooseVideo = async(sourceType?: &#39;camera&#39;) => {
    const { onChange } = this.props
    let { imageUploading } = this.state;
    if (imageUploading) {
      return;
    }
    
    const { assets } = await this.interface.chooseVideo({
      sourceType: sourceType
    });
    if(!assets) {
      return;
    }
    this.setState({
      imageUploading: true,
    });
    const res = await this.apiClient.uploadFile(assets[0].uri)   //上面封装的七牛上传方法
    if(res && res.url){
      //视频就不在组件中展示了,父组件处理
      if(onChange) {
        onChange(res.url)
      }
    }
    this.setState({
      imageUploading: false,
    });
    
  }
  private handleDelete = (ind:number) => {
    let { images } = this.state
    images.splice(ind,1)
    this.setState({
      images: [...images]
    },
      this.handleChange
    )
  }
  private handleChange = () => {
    const { onChange } = this.props
    const { images } = this.state
    if(onChange) {
      onChange(images)
    }
  }
}

4. Finally call

import Uploader from "@/components/Uploader";
...
          <Uploader
            count={6}
            onChange={urls => {
              this.setState({
                uploadImgs: urls
              })
            }}
            src={uploadImgs}
          />
...

Recommended learning: "react video tutorial"

The above is the detailed content of How to implement image selection in react. For more information, please follow other related articles on the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn