javascript - 如何在类组件中使用 React 导航 Prop ？

Question

我创建了一个共享图标，单击它可以在社交帐户(如 facebook、whatsapp、gmail 等)上共享 pdf 或图像文件。我想在类组件内传递可共享文件的 URL 链接，但出现错误。如果我对 URL 进行硬编码，那么它可以正常工作，但我如何传递从 React 导航接收到的 URL？

工作代码:

    import React, { Component } from 'react';
    import { Share, View, TouchableOpacity } from 'react-native';
import Icon from 'react-native-vector-icons/Ionicons';

    const shareOptions = {
        title: 'Download Brochure',
        url: 'https://cpbook.propstory.com/upload/project/brochure/5bc58ae6ca1cc858191327.pdf'
    }

    export default class Screen extends Component {

    onSharePress = () => Share.share(shareOptions);

    render() {
     return (
    <View> 
    <Text style={styles.infoTitle}>Share: </Text>
                            <TouchableOpacity onPress={this.onSharePress}>
                                <Icon style={{paddingLeft: 10, paddingTop: 10}}name="md-share" size={30} color="black"/>
                            </TouchableOpacity>
    </View>
    }

    }

上面的代码工作正常但下面的代码给出了错误提示 shareOptions is undefined。我怎样才能克服这个问题？我想在 shareOptions 中传递文件 URL。我从 react 导航 Prop 中获取文件 url，即 brochure。

代码:

import React, { Component } from 'react';
import { Share, View, TouchableOpacity } from 'react-native';
import Icon from 'react-native-vector-icons/Ionicons';

export default class Screen extends Component {

onSharePress = () => Share.share(shareOptions);  <---Getting error here shareOptions undefined

render() {

const project = this.props.navigation.getParam('project', null);

let { brochure } = project;

const shareOptions = {
  title: 'Download Brochure',
  url: brochure
}

return (
<View> 
<Text style={styles.infoTitle}>Share: </Text>
                        <TouchableOpacity onPress={this.onSharePress}>
                            <Icon style={{paddingLeft: 10, paddingTop: 10}}name="md-share" size={30} color="black"/>
                        </TouchableOpacity>
</View>
)

}

如何克服上述问题以及如何传递 Prop ，即上述情况中的文件 URL URL 在 brochure Prop 中。

Answer 1

只需将 shareOptions 对象作为参数传递给 onSharePress 函数，并在 onSharePress 事件处理函数中获取 shareOptions

import React, { Component } from 'react';
import { Share, View, TouchableOpacity } from 'react-native';
import Icon from 'react-native-vector-icons/Ionicons';

export default class Screen extends Component {

   onSharePress = (shareOptions) => {
      Share.share(shareOptions);  
   }

   render() {
      const { navigation } = this.props;
      const project = navigation.getParam('project', null);
      const { brochure } = project;
      const shareOptions = {
         title: 'Download Brochure',
         url: brochure
      }

   return (
     <View> 
       <Text style={styles.infoTitle}>Share: </Text>
         <TouchableOpacity onPress={() => this.onSharePress(shareOptions)}>
            <Icon style={{paddingLeft: 10, paddingTop: 10}}name="md-share" size={30} color="black"/>
         </TouchableOpacity>
     </View>
   )
  }
}