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!
import React, { useState, useEffect, useRef, } from 'react';
const OTP = (props) => {
const OTP = [];
const ref_input = [];
ref_input[0] = useRef();
ref_input[1] = useRef();
ref_input[2] = useRef();
ref_input[3] = useRef();
const focusNext = (text, index) => {
if (index < ref_input.length - 1 && text) {
ref_input[index + 1].current.focus();
}
if (index == ref_input.length - 1) {
ref_input[index].current.blur();
}
OTP[index] = text;
}
const focusPrev = (key, index) => {
if (key === "Backspace" && index !== 0) {
ref_input[index - 1].current.focus();
}
}
return (
<SafeAreaView>
<View>
<ScrollView contentInsetAdjustmentBehavior="automatic" showsVerticalScrollIndicator={false}>
<View style={loginScreenStyle.titleWrap}>
<Title style={loginScreenStyle.titleHeading}>Verify OTP</Title>
<Subheading style={loginScreenStyle.subTitle}>Enter the 4 digit code sent to your mobile number</Subheading>
</View>
<View style={loginScreenStyle.inputContainer}>
<TextInput
mode="flat"
selectionColor={Colors.primaryColor}
underlineColorAndroid="transparent"
textAlign='center'
maxLength={1}
keyboardType='numeric'
style={formScreenStyle.otpInputStyle}
autoFocus={true}
returnKeyType="next"
ref={ref_input[0]}
onChangeText={text => focusNext(text, 0)}
onKeyPress={e => focusPrev(e.nativeEvent.key, 0)}
/>
<TextInput
mode="flat"
selectionColor={Colors.primaryColor}
underlineColorAndroid="transparent"
textAlign='center'
maxLength={1}
keyboardType='numeric'
style={formScreenStyle.otpInputStyle}
ref={ref_input[1]}
onChangeText={text => focusNext(text, 1)}
onKeyPress={e => focusPrev(e.nativeEvent.key, 1)}
/>
<TextInput
mode="flat"
selectionColor={Colors.primaryColor}
underlineColorAndroid="transparent"
textAlign='center'
maxLength={1}
keyboardType='numeric'
style={formScreenStyle.otpInputStyle}
ref={ref_input[2]}
onChangeText={text => focusNext(text, 2)}
onKeyPress={e => focusPrev(e.nativeEvent.key, 2)}
/>
<TextInput
mode="flat"
selectionColor={Colors.primaryColor}
underlineColorAndroid="transparent"
textAlign='center'
maxLength={1}
keyboardType='numeric'
style={formScreenStyle.otpInputStyle}
ref={ref_input[3]}
onChangeText={text => focusNext(text, 3)}
onKeyPress={e => focusPrev(e.nativeEvent.key, 3)}
/>
</View>
</ScrollView>
</View>
</SafeAreaView >
)
}
export default OTP;
有一种方法可以捕获TextInput中的制表符。这很俗气,但总比没有好。
定义一个onChangeText处理程序,比较新输入值和旧输入值,检查是否有\t。如果找到一个,推进字段如@boredgames所示
假设变量username包含用户名的值,setUsername在存储(组件状态,redux存储等)中分派一个动作来更改它,执行如下操作:
function tabGuard (newValue, oldValue, callback, nextCallback) {
if (newValue.indexOf('\t') >= 0 && oldValue.indexOf('\t') === -1) {
callback(oldValue)
nextCallback()
} else {
callback(newValue)
}
}
class LoginScene {
focusNextField = (nextField) => {
this.refs[nextField].focus()
}
focusOnPassword = () => {
this.focusNextField('password')
}
handleUsernameChange = (newValue) => {
const { username } = this.props // or from wherever
const { setUsername } = this.props.actions // or from wherever
tabGuard(newValue, username, setUsername, this.focusOnPassword)
}
render () {
const { username } = this.props
return (
<TextInput ref='username'
placeholder='Username'
autoCapitalize='none'
autoCorrect={false}
autoFocus
keyboardType='email-address'
onChangeText={handleUsernameChange}
blurOnSubmit={false}
onSubmitEditing={focusOnPassword}
value={username} />
)
}
}
此处为具有:focus属性的输入组件的试剂溶液。
只要这个道具设置为true,字段就会被聚焦;如果这个道具设置为false,字段就不会有焦点。
不幸的是,这个组件需要定义一个:ref,我找不到其他方法来调用.focus()。我很高兴听到建议。
(defn focusable-input [init-attrs]
(r/create-class
{:display-name "focusable-input"
:component-will-receive-props
(fn [this new-argv]
(let [ref-c (aget this "refs" (:ref init-attrs))
focus (:focus (ru/extract-props new-argv))
is-focused (.isFocused ref-c)]
(if focus
(when-not is-focused (.focus ref-c))
(when is-focused (.blur ref-c)))))
:reagent-render
(fn [attrs]
(let [init-focus (:focus init-attrs)
auto-focus (or (:auto-focus attrs) init-focus)
attrs (assoc attrs :auto-focus auto-focus)]
[input attrs]))}))
https://gist.github.com/Knotschi/6f97efe89681ac149113ddec4c396cc5
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