本文例項為大家分享了Android九宮格圖片展示的具體程式碼，供大家參考，具體內容如下

一、效果圖

二、需求描述

1. 手動輸入使用者名稱和評論內容，點選提交；輸入內容被追加到右側評論列表；

2. 點選評論列表的“刪除”按鈕，彈框提示確定刪除使用者“xx”；

3. 點選“確定”，“xx”使用者發表的評論被刪除；

4. 所有評論均被刪除時，顯示“暫無評論，點選新增評論！！！”

三、程式碼實現

App.js

import React from 'react';
import './App.css';
import CommentAdd from '../src/components/CommentAdd'
import CommentList from '../src/components/CommentList'
import PropTypes from 'prop-types'
import "../src/assets/css/bootstrap.css"
 
class App extends React.Component {
 // 給元件物件指定state屬性
 // 初始化狀態
 state = {
  comments: [
   {username: "Tom",content: "React太容易了"},{username: "Jack",content: "React太難了"}
  ]
 }
 
 static propTypes = {
  comments: PropTypes.array.isRequired,addComment: PropTypes.func.isRequired,deleteComment: PropTypes.func.isRequired
 }
 
 addComment = (comment) => {
  // 將新增的評論追加到評論list上
  const {comments} = this.state
  comments.unshift(comment)
  // 更新狀態
  this.setState({comments})
 }
 deleteComment = (index) => {
  const {comments} = this.state
  comments.splice(index,1)
  this.setState({comments})
 }
 
 render() {
  const {comments} = this.state
  return (
   <div>
    <header className="site-header jumbotron">
     <div className="container">
      <div className="row">
       <div className="col-xs-12">
        <h2>評論管理列表</h2>
       </div>
      </div>
     </div>
    </header>
    <div className="container">
     <CommentAdd addComment={this.addComment}/>
     <CommentList comments={comments} deleteComment={this.deleteComment}/>
    </div>
   </div>
  );
 }
}
 
export default App;

CommentAdd.js

import React,{Component} from 'react';
import PropTypes from 'prop-types'
import "../assets/css/bootstrap.css"
 
class CommentAdd extends Component {
 
 state = {
  username: "",content: ""
 }
 
 static propTypes = {
  addComment: PropTypes.func.isRequired
 }
 handleNameChange = (event) => {
  const username = event.target.value
  this.setState({username});
 }
 handleContentChange = (event) => {
  const content = event.target.value
  this.setState({content});
 }
 handleSubmit = () => {
  const comment = this.state
  this.props.addComment(comment)
  // 清楚輸入資料
  this.setState({
   username: "",content: ""
  });
 }
 
 render() {
  const {username,content} = this.props
  return (
   <div className="col-md-4">
    <form className="form-horizontal">
     <div className="form-group">
      <label>使用者名稱：</label>
      <input type="text" className="form-control" placeholder="請輸入使用者名稱" value={username}
        onChange={this.handleNameChange}/><br/>
     </div>
     <div className="form-group">
      <label>評論內容：</label>
      <textarea className="form-control" rows="6" placeholder="請輸入評論內容"
         value={content} onChange={this.handleContentChange}>
      </textarea>
     </div>
     <div className="form-group">
      <div className="col-sm-offset-2 col-sm-10">
       <button type="button" className="btn btn-default pull-right"
         onClick={this.handleSubmit}>提交
       </button>
      </div>
     </div>
    </form>
   </div>
  );
 }
}
 
export default CommentAdd;

CommentList.js

import React,{Component} from 'react';
import CommentItem from "./CommentItem";
import PropTypes from 'prop-types'
import "../assets/css/comment_list.css"
 
class CommentList extends Component {
 
 static propTypes = {
  comments: PropTypes.array.isRequired,deleteComment: PropTypes.func.isRequired
 }
 
 render() {
  const {comments,deleteComment} = this.props
  const display = comments.length === 0 ? "block" : "none"
  return (
 
   <div className="col-md-8">
    <h4>評論回覆：</h4>
    <h5 style={{display}}>暫無評論，點選新增評論！！！</h5>
    <ul>
     {
      comments.map((comment,index) => <li key={index}><CommentItem comments={comment} index={index}
                      deleteComment={deleteComment}/>
      </li>)
     }
    </ul>
   </div>
  );
 }
}
 
export default CommentList;

CommentItem.js

import React,{Component} from 'react';
import PropTypes from 'prop-types'
import "../assets/css/comment_item.css"
 
class CommentItem extends Component {
 static propTypes = {
  comments: PropTypes.array.isRequired,deleteComment: PropTypes.func.isRequired,index: PropTypes.number.isRequired
 }
 
 handleDeleteComment = () => {
  const {comments,deleteComment,index} = this.props
  if (window.confirm(`確定刪除${comments.username}嘛？`)) {
   deleteComment(index)
  }
 }
 
 render() {
  const {comments} = this.props
  return (
   <div className="list-group-item">
    <div className="handle">
     <a href="javascript:;" rel="external nofollow" onClick={this.handleDeleteComment}>刪除</a>
    </div>
    <p className="user"><span>{comments.username}</span><span>說：</span></p>
    <p className="centence">{comments.content}</p>
   </div>
  );
 }
}
 
export default CommentItem;

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支援我們。