Implementing SharePoint Operations Using React.js - Part Two

Here, you will see how React JavaScript plugins can be plugged in to SharePoint pages for rendering the data.

In my previous post, I explained about the basic terminology required for implementing React JavaScript logic on SharePoint pages.

• Implementing SharePoint Operations Using React.js - Part One

Note

The core logic is implemented inside the class. The class can be created in two ways:

• React traditionally provides React.createClass method to create the component classes.
• Recently updated React JS version allows us to create the classes, using the React.Component method supported, using ES6 modules.

These two methods differ in implementation approaches. In this article, I will create the components, using ES6 modules.

Steps Involved

Upload the necessary plugins onto SharePoint site libraries. Instead of the local copies, the plugins can be directly accessed from cdn sites.

Create the content editor Webpart manually on the site. The custom Web parts can also be used. Inside the Web part, refer to the plugins explicitly.

1. <script src="https://unpkg.com/react@latest/dist/react.js"></script>  
2. <script src="https://unpkg.com/react-dom@latest/dist/react-dom.js"></script>  
3. <script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>   

Add the root HTML tag for appending the content, using JSX.

1. <div id="listInformation"></div>  

JSX content is written inside the script tag, which is of the type text/babel. Babel plugin helps the code to be executed on the Browsers.

Create the class with custom name, using React.Component method. Class should contain a constructor, which has super() method declared. Set the state container with the necessary variables. In this sample, list name, descriptions, template ID and items count are stored.

1. constructor(){  
2.      super();  
3.      this.state = {  
4.          listInfo: {listName: '',listDescription: '', templateId:0, itemCount: 0}  
5.      }  
6.  }  

Since the data needs to be rendered on the page load, one of the life cycle methods is used to retrieve the list information and set it into the state variables. In this sample, the data is retrieved asynchronously. Thus, componentDidMount method is used. The custom function is created for retrieving the list information. 

1. GetListInfo(){  
2.     var reactHandler = this;  
3.   
4.     var request = new XMLHttpRequest();  
5.     request.open('GET', "/_api/web/lists/getbytitle('TestList')", true);  
6.     request.setRequestHeader('Content-Type', 'application/json; charset=UTF-8');  
7.           
8.     //this callback gets called when the server responds to the ajax call  
9.     request.onreadystatechange = function(){  
10.         if (request.readyState === 4 && request.status === 200){  
11.             var returnedJson = JSON.parse(request.responseText);  
12.               
13.             reactHandler.setState({  
14.                 listInfo:  
15.                 {  
16.                     listName: returnedJson.Title,  
17.                     listDescription: returnedJson.Description,  
18.                     templateId: returnedJson.BaseTemplate,  
19.                     itemCount: returnedJson.ItemCount  
20.                 }  
21.             });  
22.         }  
23.         else if (request.readyState === 4 && request.status !== 200){  
24.             console.log('Error in retrieving data!');  
25.         }  
26.     };  
27.     request.send();  
28. } 

Note

Event handlers can also be used instead of the method shown above, if the data retrieval is based on the user action.

The render method displays the data. HTML is inserted into this method. The state variables are referred to in this method to display the necessary information.

1. render(){  
2.     return(  
3.     <div>  
4.         <h2>{this.state.listInfo.listName} List Information:</h2>  
5.         <p>{this.state.listInfo.listDescription}</p>  
6.         <p>Template : {this.state.listInfo.templateId}</p>  
7.         <p>Total Items: {this.state.listInfo.itemCount}</p>  
8.     </div>  
9.     );  
10. }   

The render method is called to render the component data.

1. ReactDOM.render(<ListJS />, document.getElementById('listInformation'));   

The code snippet given below shows the entire logic to retrieve the list information.

1. <script src="https://unpkg.com/react@latest/dist/react.js"></script>  
2. <script src="https://unpkg.com/react-dom@latest/dist/react-dom.js"></script>  
3. <script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>  
4.   
5. <div id="listInformation"></div>  
6. <script type="text/babel">  
7.       
8.     class ListJS extends React.Component{  
9.         constructor(){  
10.             super();  
11.             this.state = {  
12.                 listInfo: {listName: '',listDescription: '', templateId:0, itemCount: 0}  
13.             }  
14.         }  
15.         componentDidMount() {  
16.             // Custom function to retrieve the list info  
17.             this.GetListInfo();  
18.         }  
19.   
20.         GetListInfo(){  
21.             var reactHandler = this;  
22.   
23.             var request = new XMLHttpRequest();  
24.             request.open('GET', "/_api/web/lists/getbytitle('TestList')", true);  
25.             request.setRequestHeader('Content-Type', 'application/json; charset=UTF-8');  
26.                   
27.             //this callback gets called when the server responds to the ajax call  
28.             request.onreadystatechange = function(){  
29.                 if (request.readyState === 4 && request.status === 200){  
30.                     var returnedJson = JSON.parse(request.responseText);  
31.                       
32.                     reactHandler.setState({  
33.                         listInfo:  
34.                         {  
35.                             listName: returnedJson.Title,  
36.                             listDescription: returnedJson.Description,  
37.                             templateId: returnedJson.BaseTemplate,  
38.                             itemCount: returnedJson.ItemCount  
39.                         }  
40.                     });  
41.                 }  
42.                 else if (request.readyState === 4 && request.status !== 200){  
43.                     console.log('Error in retrieving data!');  
44.                 }  
45.             };  
46.             request.send();  
47.         }  
48.   
49.         render(){  
50.             return(  
51.             <div>  
52.                 <h2>{this.state.listInfo.listName} List Information:</h2>  
53.                 <p>{this.state.listInfo.listDescription}</p>  
54.                 <p>Template : {this.state.listInfo.templateId}</p>  
55.                 <p>Total Items: {this.state.listInfo.itemCount}</p>  
56.             </div>  
57.             );  
58.         }  
59.       
60.     }  
61.   
62.     ReactDOM.render(<ListJS />, document.getElementById('listInformation'));  
63. </script>   

The snapshot given below shows the Webpart, which shows the list information, using the logic stated above.

Implementing SharePoint Operations Using React.js - Part One

In this series, you will learn how to implement basic SharePoint operations using React JavaScript libraries.

Here, you will learn the React JavaScript library basics required for implementing SharePoint operations.

ReactJS

• React is a front-end library developed and licensed by Facebook.
• React is a declarative, efficient, and flexible JavaScript library for building user interfaces.
• It is famous for 'V' in MVC, which handles view layer on the web.
• Using ReactJS, we can build reusable components. 

There are multiple ways of implementing the React JavaScript logic into SharePoint. In this article, I will use the React JavaScript libraries stored on the web. Additionally, Babel compiler is required for compiling the JSX content.

The library files referenced are,

• react.js
• react-dom.js
• babel.min.js 

JSX

The core functionality is written on JSX. Here, Babel compiler is used to transform the JSX content to JS.

• JSX content is embedded with in the script tag, which is of the type text/babel.
• JSX contains JavaScript with HTML/XML in it.
• JSX is faster, type safe and object-oriented programming language. 
• JSX is not the globally accepted standard, so it is not supported on browsers.

Some of the React JavaScript basics used for our implementation are explained below. 

1. ComponentsComponents help us split the code/UI in multiple pieces. The component contains a constructor and methods.
2. StateState stores the data. The data can be in multiple forms. The data can be a string, number, array, etc.
3. PropsProps are attributes defined in the components. These are immutable and passed as arguments for rendering the HTML. propTypes are used for validating the props.
4. RenderIt is a method, which returns the HTML content that needs to be displayed on the page.
5. ConstructorConstructor declares the variables, handlers and the methods.
6. Component Life cycleThere are predefined set of methods executed when the component is executed. The life cycle methods are componentWillMount, componentDidMount, componentWillReceiveProps, shouldComponentUpdate, componentWillUpdate, componentDidUpdate, and componentWillUnmount. 

The React JavaScript library basics can be found on the official site https://facebook.github.io/react.

Prerequisites

In the sample, I will refer the React JavaScript and Babel plugins directly on the content editor webpart.

• React 
• React DOM 
• Babel

The sample JSX content will look like below.

1. class Sample extends React.Component {  
2.     constructor(){  
3.         super();  
4.         this.state = {  
5.             data:''  
6.         }  
7.     }  
8.     componentWillMount(){  
9.     }  
10.     componentDidMount() {  
11.     }  
12.     // Other Life Cycle Methods  
13.   
14.     render(){  
15.         return(  
16.             <div>  
17.                 HTML  
18.             </div>  
19.         );  
20.     }  
21. }  
22. ReactDOM.render(<Sample />, document.getElementById('divid'));   

  

Next, I will explain how to implement the SharePoint functionalities using React JavaScript libraries.