依賴

代碼

import React,{Component} from 'react';
import './login.css';
import PropTypes from 'prop-types';
class Login extends Component{
    constructor(){
        super();
        this.state = {
            username:"",
            password:""
        }
    }
    static contextTypes = {
        router:PropTypes.object.isRequired
    };

    handleLogin(event){
        const path = '/register';
        this.context.router.push(path);
    }

    handleUsername(event){
        let value = event.target.value;
        this.setState({
            username:value
        });
    }

    handlePassword(event){
        let value = event.target.value;
        this.setState({
            password:value
        });
    }

    render() {
        return(
            <div className="login">
                <h1>LOGIN</h1>
                <div className="login-list">
                    <div className="login-part">
                        <span className="login-name">用戶名:</span>
                        <input type="text" className="login-input" onChange={this.handleUsername.bind(this)}/>
                    </div>
                    <div className="login-part">
                        <span className="login-name">密碼:</span>
                        <input type="password" className="login-input" onChange={this.handlePassword.bind(this)}/>
                    </div>
                    <div className="login-part">
                        <button className="login-go" onClick={this.handleLogin.bind(this)}>登陸</button>
                    </div>
                </div>
            </div>
        )
    }
}

export default Login;

怎么才能把警告解決