1.7 HelloWorld adding views

Model: Managing Data

Controller: Perform tasks, set or get the state of the model, request view display

View: Shows what is selected by the control

(1) Setting the controller

Jcontroller is a class that manages the controller and adds the following code to site/helloworld.php.

<?php//  No Direct access to this filedefineddie (' Restricted access '  // Import Joomla Controller Libraryjimport (' Joomla.application.component.controller '// Get An instance of the controller prefixed by HelloWorld
$controller = jcontrollerlegacy::getinstance (' HelloWorld ');//Perform The Request task $input= Jfactory::getapplication (),input; $controller->execute ($input->getcmd (' Task '//  Redirect if set by the ControlleR$controller->redirect ();
Jcontrollerlegacy::getinstance (' HelloWorld ');(Note that the 3.x version uses Jcontrollerlegacy if Jcontroller is used on the crossing web)
Create a controller class named Helloworldcontroller, and Joomla will look for the declaration of this class in controller.php.
So write the following code in the site/controller.php file:
 
 
 <? PHP  //  No direct access to the This file  Span style= "COLOR: #008080" >defined  (' _jexec ') or die  (' Restricted access '  //  import JOOMLA Controller library  Jimport (' Joomla.application.component.controller '  /*  * * Hello World Component Controller  */ class  Helloworldcontroller extends  jcontrollerlegacy (note 3. X to inherit jcontrollerlegacy) {}  
 when you do not specify a value for a task, the default task is executed, and the default task task is display, So create the display method in Helloworldcontroller. 

(2) Setting the view

When Jcontroller wants to show a view, he will find it from the directory component/com_helloworld/views/helloworld/directory

site/views/helloworld/view.html.php

<?PHP//No Direct Access to the This filedefined(' _jexec ') or die(' Restricted access '); //Import Joomla View libraryJimport (' Joomla.application.component.view '); /** * HTML View class for the HelloWorld Component*/classHelloworldviewhelloworld Extendsjviewlegacy (Note 3.x to inherit jviewlegacy) {    //overwriting JView Display method    functionDisplay$TPL=NULL){    //Assign Data to the view    $this->msg= ' Hello World '; //Display The ViewParent::d Isplay ($TPL);}}
The display method of the JView class is called by the task method of the Jcontroller class, in which case the display method displays the tmpl/default.php file.
site/views/helloworld/tmpl/default.php
<? PHP // No Direct Access to the This file defined  die (' Restricted access ');? >$this->msg;? >This template file will be included in the JView class, so $this refers to the Helloworldviewhelloworld class.
Helloworld.xml
  
<?xmlversion= "1.0" encoding= "Utf-8 "?><extensiontype= "Component"version= "2.5.0"Method= "Upgrade"><name>Hello world!</name><!--The following elements is optional and free of formatting constraints -<CreationDate>November 2009</CreationDate><author>John Doe</author><Authoremail>[Email protected]</Authoremail><Authorurl>http://www.example.org</Authorurl><Copyright>Copyright Info</Copyright><License>License Info</License><!--The version string is recorded in the Components table -<version>0.0.2</version><!--The description is optional and Defaults to the name -<Description>Description of the Hello World component ...</Description><Update><!--Runs on Update; New in 2.5 -<Schemas><Schemapathtype= "MySQL">Sql/updates/mysql</Schemapath></Schemas></Update> <!--Site Main File Copy section--><!--Note the folder Attribute:this attribute describes the folder to copy from the "To install therefore files" Copied in this section is copied from/site/in the package -<Filesfolder= "Site"><filename>Index.html</filename><filename>helloworld.php</filename><filename>controller.php</filename><folder>Views</folder></Files> <Administration>    <!--Administration Menu Section -    <Menu>Hello world!</Menu>    <!--administration Main File Copy section--><!--Note the folder Attribute:this attribute describes the folder to copy from in the package to install ther Efore files copied in this section is copied from/admin/in the package -    <Filesfolder= "Admin">        <!--Admin Main File Copy section -        <filename>Index.html</filename>        <filename>helloworld.php</filename>        <!--SQL Files section -        <folder>Sql</folder>    </Files></Administration> </extension>
 

1.7 HelloWorld adding views