You need to add the function of viewing and commenting to the Blog

1. Create the viewing function

Add the show() method in application.java

public static void show(Long id) {
Post post = Post.findById( id);
render(post);
}

Create app/views/Application/show.html

#{extends 'main.html' /}
#{set title:post.title /}

#{display post:post, as:'full' /}

Add link in page template

Visit Blog

${_post.title}

Return to homepage

${blogTitle}

2. Create routing rules

Current page URL http://localhost:9000/application /show?id=3

is obtained by parsing the rule * /{controller}/{action} {controller}.{action}

Create a new Route before

GET /posts/{id}                                 Application. show

The access path becomes http://localhost:9000/posts/3

More routing syntax reference: http://play-framework.herokuapp.com/zh/routes#syntax

3. Add page navigation

Add method to Post class, PRevious()next()

public Post previous() {
return Post.find("postedAt < ? order by postedAt desc", postedAt).first();
)

          #{if post.previous()}
                                                                                                               id)}">
                                                                                                            
• 
                                                          < ;/li>
  #{/if}

4. Add comment box

Application Controller adds method postComment()

public static void postComment(Long postId, String author, String content ) {
Post post = Post.findById(postId);
post.addComment(author, content);
show(postId);
}


　

Modify show.html

Post a comment< /h3>

#{form @Application.postComment(post.id)}

                                                                                                      " name="author" id="author" />

                                                                                                                 "content" id="content">

;

#{/form}

　

5. Add verification to verify that Author and Content are not empty

import play.data.validation.*;

public static void postComment(Long postId, @Required String author, @ Required String content) {

Post post = Post.findById(postId);

if (validation.hasErrors()) {

render("Application/show.html", post);
}
post.addComment(author, content );
show(postId);
}　




Edit form, display error

#{form @Application.postComment(post.id)}

   #{ifErrors}
       

           All fields are required!
       

   #{/ifErrors}

   

       Your name:
       
   

   

       Your message:
       ${params.content}
   

   

       
   

#{/form}

　　

6.优化客户提示

加载jquery的类库

 

修改Show.html

#{if Flash.success}
　　

${flash.success}

#{/if}

#{display post:post, as:'full' /}

　　

添加Comment成功的提示

post.addComment(author, content);
flash.success("Thanks for posting %s", author);

　　

添加路由

POST    /posts/{postId}/comments                Application.postComment

 以上就是PlayFramework完整实现一个APP（六）的内容，更多相关内容请关注PHP中文网（m.sbmmt.com）！