清除无状态React组件中的输入

Question

I want to implement an X icon inside Input component that will clear the input field. I can easily do it if I control the state. But is it actually possible with stateless component? I use react-semantic-ui, their stateful components have auto controlled state.

So I want to create an input that can be used like this:

 //Controlled class App extends React.Component { state = { value:'' } onChange = (event, props) => { this.setState({value: props.value}); } onClearInput = () => { this.setState({value: ''}); } render() { return ( <MyInput clearable value={this.state.value} onChange={this.onChange} onClearInput={this.onClearInput} /> ) } } 

Or

 // Uncontrolled class App extends React.Component { onChange = (event, props) => { doSomething(props.value); } render() { return ( <MyInput clearable onChange={this.onChange} /> ) } } 

In the second example, clearable feature will not work because we're not controlling the value.

MyInput can be implemented like this:

 import React from 'react'; import { Input } from 'semantic-ui-react'; import ClearIcon from './ClearIcon'; function MyInput(props) { const prepareProps = {...props}; if (props.clearable) { prepareProps.icon=<ClearIcon onClick={props.onClearInput} />; delete prepareProps.clearable; } delete prepareProps.onClearInput; return ( <div className="my-input"> <Input {...prepareProps} /> </div> ); } ...etc. 

My problems:

1. clearable feature must work in both controlled and uncontrolled manner.

2. clearable feature should not require a handler. It would be nice to just provide a prop and handle the render and behavior of the X button under the hood.

I don't see any way to make this work. Any ideas?

Answer 1

Allowing the user of your component to set the value via props and still being able to clear the input can be easily achieved, eg like this:

class MyInput extends React.Component {
    constructor(props) {
        super(props);
        this.state = {value: props.value || ''};
    }

    handleChange = event => {
        const { onChange } = this.props;
        this.setState({ value: event.currentTarget.value });
        onChange && onChange(event);
    };

    handleClear = () => {
        const { onClearInput } = this.props;
        this.setState({ value: "" });
        onClearInput && onClearInput();
    };

    render() {
        const { value } = this.state;
        const { clearable, onChange, ...inputProps } = this.props;

        const clearIcon = clearable && <ClearIcon onClick={this.handleClear} />;

        return (
            <div className="my-input">
                <Input value={value} icon={clearIcon} onChange={this.handleChange} {...inputProps} />
            </div>
        );
    }
}

You could even make it more composable by using an hoc or render props as proposed by @pkuzhel.

Look at this codesandbox example to see it in action.

Answer 2

@Andrey

Would you try this below code? and let me know if that resolves your issue.

import React, { Component } from 'react';
import { Input, Button } from 'semantic-ui-react'

class App extends Component {
  clear = () => {
    console.log(this.inputRef.target.value);
    this.inputRef.target.value = '';
  }
  render() {
    return (
      <div className="App">
        <Input placeholder='Search...' onChange={(input) => {input.persist(); this.inputRef = input}} />
        <Button onClick={this.clear}>Clear</Button>
      </div>
    );
  }
}