React Native - Modal

• 

  简述

  在本章中，我们将向您展示如何在 React Native 中使用模态组件。

  现在让我们创建一个新文件：ModalExample.js

  我们将把逻辑放在里面ModalExample. 我们可以通过运行更新初始状态toggleModal.

  通过运行更新初始状态后toggleModal，我们将设置visible属性到我们的模态。当状态改变时，这个道具将被更新。

  这onRequestClose对于 Android 设备是必需的。
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  app.js

  
  import React, { Component } from 'react'
  import WebViewExample from './modal_example.js'
  const Home = () => {
     return (
        <WebViewExample/>
     )
  }
  export default Home;
  

• 

  modal_example.js

  
  import React, { Component } from 'react';
  import { Modal, Text, TouchableHighlight, View, StyleSheet}
  from 'react-native'
  class ModalExample extends Component {
     state = {
        modalVisible: false,
     }
     toggleModal(visible) {
        this.setState({ modalVisible: visible });
     }
     render() {
        return (
           <View style = {styles.container}>
              <Modal animationType = {"slide"} transparent = {false}
                 visible = {this.state.modalVisible}
                 onRequestClose = {() => { console.log("Modal has been closed.") } }>
                 
                 <View style = {styles.modal}>
                    <Text style = {styles.text}>Modal is open!</Text>
                    
                    <TouchableHighlight onPress = {() => {
                       this.toggleModal(!this.state.modalVisible)}}>
                       
                       <Text style = {styles.text}>Close Modal</Text>
                    </TouchableHighlight>
                 </View>
              </Modal>
              
              <TouchableHighlight onPress = {() => {this.toggleModal(true)}}>
                 <Text style = {styles.text}>Open Modal</Text>
              </TouchableHighlight>
           </View>
        )
     }
  }
  export default ModalExample
  const styles = StyleSheet.create ({
     container: {
        alignItems: 'center',
        backgroundColor: '#ede3f2',
        padding: 100
     },
     modal: {
        flex: 1,
        alignItems: 'center',
        backgroundColor: '#f7021a',
        padding: 100
     },
     text: {
        color: '#3f2949',
        marginTop: 10
     }
  })
  

  我们的起始屏幕将如下所示 -

  

  如果我们单击按钮，模态将打开。