我定义了两个TextInput字段如下:

<TextInput 
   style = {styles.titleInput}
   returnKeyType = {"next"}
   autoFocus = {true}
   placeholder = "Title" />
<TextInput
   style = {styles.descriptionInput}          
   multiline = {true}
   maxLength = {200}
   placeholder = "Description" />

但在按下键盘上的“next”按钮后,我的react-native应用程序并没有跳转到第二个TextInput字段。我怎样才能做到呢?

谢谢!


当前回答

你不需要裁判也可以做到。这种方法是首选的,因为引用会导致脆弱的代码。React文档建议在可能的情况下寻找其他解决方案:

If you have not programmed several apps with React, your first inclination is usually going to be to try to use refs to "make things happen" in your app. If this is the case, take a moment and think more critically about where state should be owned in the component hierarchy. Often, it becomes clear that the proper place to "own" that state is at a higher level in the hierarchy. Placing the state there often eliminates any desire to use refs to "make things happen" – instead, the data flow will usually accomplish your goal.

相反,我们将使用一个状态变量来聚焦第二个输入字段。

Add a state variable that we'll pass as a prop to the DescriptionInput: initialState() { return { focusDescriptionInput: false, }; } Define a handler method that will set this state variable to true: handleTitleInputSubmit() { this.setState(focusDescriptionInput: true); } Upon submitting / hitting enter / next on the TitleInput, we'll call handleTitleInputSubmit. This will set focusDescriptionInput to true. <TextInput style = {styles.titleInput} returnKeyType = {"next"} autoFocus = {true} placeholder = "Title" onSubmitEditing={this.handleTitleInputSubmit} /> DescriptionInput's focus prop is set to our focusDescriptionInput state variable. So, when focusDescriptionInput changes (in step 3), DescriptionInput will re-render with focus={true}. <TextInput style = {styles.descriptionInput} multiline = {true} maxLength = {200} placeholder = "Description" focus={this.state.focusDescriptionInput} />

这是避免使用refs的好方法,因为refs会导致更脆弱的代码:)

编辑:h/t @LaneRettig指出,你需要用一些添加的道具和方法来包装React Native TextInput,以获得对焦点的响应:

    // Props:
    static propTypes = { 
        focus: PropTypes.bool,
    } 

    static defaultProps = { 
        focus: false,
    } 

    // Methods:
    focus() {
        this._component.focus(); 
    } 

    componentWillReceiveProps(nextProps) {
        const {focus} = nextProps; 

        focus && this.focus(); 
    }

其他回答

使用回调引用而不是遗留的字符串引用:

<TextInput
    style = {styles.titleInput}
    returnKeyType = {"next"}
    autoFocus = {true}
    placeholder = "Title"
    onSubmitEditing={() => {this.nextInput.focus()}}
/>
<TextInput
    style = {styles.descriptionInput}  
    multiline = {true}
    maxLength = {200}
    placeholder = "Description"
    ref={nextInput => this.nextInput = nextInput}
/>

我就是这样做到的。下面的例子使用了React 16.3中引入的React. createref () API。

class Test extends React.Component {
  constructor(props) {
    super(props);
    this.secondTextInputRef = React.createRef();
  }

  render() {
    return(
        <View>
            <TextInput
                placeholder = "FirstTextInput"
                returnKeyType="next"
                onSubmitEditing={() => { this.secondTextInputRef.current.focus(); }}
            />
            <TextInput
                ref={this.secondTextInputRef}
                placeholder = "secondTextInput"
            />
        </View>
    );
  }
}

我想这对你有帮助。

下面是如何为reactjs的电话代码输入实现这一点

import React, { useState, useRef } from 'react';

function Header(props) {

  const [state , setState] = useState({
        phone_number:"",
        code_one:'',
        code_two:'',
        code_three:'',
        code_four:'',
        submitted:false,

  })

   const codeOneInput = useRef(null);
   const codeTwoInput = useRef(null);
   const codeThreeInput = useRef(null);
   const codeFourInput = useRef(null);

   const handleCodeChange = (e) => {
        const {id , value} = e.target
        if(value.length < 2){
            setState(prevState => ({
                ...prevState,
                [id] : value
            }))
            if(id=='code_one' && value.length >0){
                codeTwoInput.current.focus();
            }
            if(id=='code_two'  && value.length >0){
                codeThreeInput.current.focus();
            }
            if(id=='code_three'  && value.length >0){
                codeFourInput.current.focus();
            }
        }
    }

    const sendCodeToServer = () => {

         setState(prevState => ({
                ...prevState,
                submitted : true,
          }))
  let codeEnteredByUser = state.code_one + state.code_two + state.code_three + state.code_four

        axios.post(API_BASE_URL, {code:codeEnteredByUser})
        .then(function (response) {
            console.log(response)
        })

   }

   return(
        <>

           <div className="are">
                 <div className="POP-INN-INPUT">
                                        <input type="text" id="code_one" ref={codeOneInput}    value={state.code_one}  onChange={handleCodeChange} autoFocus/>
                                        <input type="text" id="code_two"  ref={codeTwoInput}  value={state.code_two} onChange={handleCodeChange}/>
                                        <input type="text" id="code_three"  ref={codeThreeInput} value={state.code_three}  onChange={handleCodeChange}/>
                                        <input type="text" id="code_four" ref={codeFourInput}  value={state.code_four}  onChange={handleCodeChange}/>
                                    </div>

            <button disabled={state.submitted} onClick={sendCodeToServer}>
   
    </div>

       </>
    )
}
export default

如果你正在使用NativeBase作为UI组件,你可以使用这个示例

<Item floatingLabel>
    <Label>Title</Label>
    <Input
        returnKeyType = {"next"}
        autoFocus = {true}
        onSubmitEditing={(event) => {
            this._inputDesc._root.focus(); 
        }} />
</Item>
<Item floatingLabel>
    <Label>Description</Label>
    <Input
        getRef={(c) => this._inputDesc = c}
        multiline={true} style={{height: 100}} />
        onSubmitEditing={(event) => { this._inputLink._root.focus(); }} />
</Item>

使用react-native 0.45.1我还遇到了问题,试图在按下用户名TextInput的返回键后将焦点设置在密码TextInput上。

在尝试了这里的大多数顶级解决方案之后,我在github上找到了一个解决方案,满足了我的需求: https://github.com/shoutem/ui/issues/44#issuecomment-290724642

总结一下:

import React, { Component } from 'react';
import { TextInput as RNTextInput } from 'react-native';

export default class TextInput extends Component {
    render() {
        const { props } = this;

        return (
            <RNTextInput
                {...props}
                ref={(input) => props.inputRef && props.inputRef(input)}
            />
        );
    }
}

然后我这样使用它:

import React, {Component} from 'react';
import {
    View,
} from 'react-native';
import TextInput from "../../components/TextInput";

class Login extends Component {
    constructor(props) {
        super(props);
        this.passTextInput = null
    }

    render() {
        return (
            <View style={{flex:1}}>
                <TextInput
                    style={{flex:1}}
                    placeholder="Username"
                    onSubmitEditing={(event) => {
                        this.passTextInput.focus()
                    }}
                />

                <TextInput
                    style={{flex:1}}
                    placeholder="Password"
                    inputRef={(input) => {
                        this.passTextInput = input
                    }}
                />
            </View>
        )
    }
}