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-rw-r--r-- | demos/quickstart/protected/pages/Tutorial/fr/CurrencyConverter.page | 405 | ||||
-rw-r--r-- | demos/quickstart/protected/pages/Tutorial/fr/chat1.png | bin | 0 -> 10533 bytes | |||
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diff --git a/demos/quickstart/protected/pages/Tutorial/fr/AjaxChat.page b/demos/quickstart/protected/pages/Tutorial/fr/AjaxChat.page new file mode 100644 index 00000000..fc1997c8 --- /dev/null +++ b/demos/quickstart/protected/pages/Tutorial/fr/AjaxChat.page @@ -0,0 +1,757 @@ +<com:TContent ID="body"> + <h1 id="18008">Building an AJAX Chat Application</h1> + <p id="90081" class="block-content">This tutorial introduces the Prado web application framework's + <a href="?page=Database.ActiveRecord">ActiveRecord</a> + and <a href="?page=ActiveControls.Home">Active Controls</a> to build a Chat + web application. It is assumed that you + are familiar with PHP and you have access to a web server that is able to serve PHP5 scripts. + This basic chat application will utilize the following ideas/components in Prado. + </p> + <ul id="u1" class="block-content"> + <li>Building a custom User Manager class.</li> + <li>Authenticating and adding a new user to the database.</li> + <li>Using ActiveRecord to interact with the database.</li> + <li>Using Active Controls and callbacks to implement the user interface.</li> + <li>Separating application logic and application flow.</li> + </ul> + + <p id="90082" class="block-content">In this tutorial you will build an AJAX Chat web application that allows + multiple users to communicate through their web browser. + The application consists of two pages: a login page + that asks the user to enter their nickname and the main application chat + page. + You can try the application <a href="../chat/index.php">locally</a> or at + <a href="http://www.pradosoft.com/demos/chat/">Pradosoft.com</a>. + The main application chat page is shown bellow. + <img src=<%~ chat1.png %> class="figure" /> + </p> + + <h1 id="18009">Download, Install and Create a New Application</h1> + <p id="90083" class="block-content">The download and installation steps are similar to those in + the <a href="?page=Tutorial.CurrencyConverter#download">Currency converter tutorial</a>. + To create the application, we run from the command line the following. + See the <a href="?page=GettingStarted.CommandLine">Command Line Tool</a> + for more details. +<com:TTextHighlighter Language="text" CssClass="source block-content" id="code_90027"> +php prado/framework/prado-cli.php -c chat +</com:TTextHighlighter> + </p> + + <p id="90084" class="block-content">The above command creates the necessary directory structure and minimal + files (including "index.php" and "Home.page") to run a Prado web application. + Now you can point your browser's URL to the web server to serve up + the <tt>index.php</tt> script in the <tt>chat</tt> directory. + You should see the message "Welcome to Prado!" + </p> + + <h1 id="18010">Authentication and Authorization</h1> + <p id="90085" class="block-content">The first task for this application is to ensure that each user + of the chat application is assigned with a unique (chosen by the user) + username. To achieve this, we can secure the main chat application + page to deny access to anonymous users. First, let us create the <tt>Login</tt> + page with the following code. We save the <tt>Login.php</tt> and <tt>Login.page</tt> + in the <tt>chat/protected/pages/</tt> directory (there should be a <tt>Home.page</tt> + file created by the command line tool). + </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90028"> +<?php +class Login extends TPage +{ +} +?> +</com:TTextHighlighter> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90029"> +<!doctype html public "-//W3C//DTD XHTML 1.0 Strict//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + <title>Prado Chat Demo Login</title> +</head> +<body> +<com:TForm> + <h1 class="login">Prado Chat Demo Login</h1> + <fieldset class="login"> + <legend>Please enter your name:</legend> + <div class="username"> + <com:TLabel ForControl="username" Text="Username:" /> + <com:TTextBox ID="username" MaxLength="20" /> + <com:TRequiredFieldValidator + ControlToValidate="username" + Display="Dynamic" + ErrorMessage="Please provide a username." /> + </div> + <div class="login-button"> + <com:TButton Text="Login" /> + </div> +</com:TForm> +</body> +</html> +</com:TTextHighlighter> + <p id="90086" class="block-content">The login page contains + a <com:DocLink ClassPath="System.Web.UI.TForm" Text="TForm" />, + a <com:DocLink ClassPath="System.Web.UI.WebControls.TTextBox" Text="TTextBox" />, + a <com:DocLink ClassPath="System.Web.UI.WebControls.TRequiredFieldValidator" Text="TRequiredFieldValidator" /> + and a <com:DocLink ClassPath="System.Web.UI.WebControls.TButton" Text="TButton" />. The resulting + page looks like the following (after applying some a style sheet). + <img src=<%~ chat2.png %> class="figure" /> + If you click on the <tt>Login</tt> button without entering any + text in the username textbox, an error message is displayed. This is + due to the <com:DocLink ClassPath="System.Web.UI.WebControls.TRequiredFieldValidator" Text="TRequiredFieldValidator" /> + requiring the user to enter some text in the textbox before proceeding. + </p> +<h2 id="18019">Securing the <tt>Home</tt> page</h2> +<p id="90087" class="block-content">Now we wish that if the user is trying to access the main application +page, <tt>Home.page</tt>, before they have logged in, the user is presented with +the <tt>Login.page</tt> first. We add a <tt>chat/protected/application.xml</tt> configuration +file to import some classes that we shall use later. +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90030"> +<?xml version="1.0" encoding="utf-8"?> +<application id="Chat" Mode="Debug"> + <paths> + <using namespace="System.Data.*" /> + <using namespace="System.Data.ActiveRecord.*" /> + <using namespace="System.Security.*" /> + <using namespace="System.Web.UI.ActiveControls.*" /> + </paths> +</application> +</com:TTextHighlighter> +Next, we add a <tt>chat/protected/pages/config.xml</tt> configuration file to +secure the <tt>pages</tt> directory. +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90031"> +<?xml version="1.0" encoding="utf-8"?> +<configuration> + <modules> + <module id="users" class="TUserManager" /> + <module id="auth" class="TAuthManager" UserManager="users" LoginPage="Login" /> + </modules> + <authorization> + <allow pages="Login" users="?" /> + <allow roles="normal" /> + <deny users="*" /> + </authorization> +</configuration> +</com:TTextHighlighter> +We setup the authentication using the default classes as explained in the +<a href="?page=Advanced.Auth">authentication/authorization quickstart</a>. +In the authorization definition, we allow anonymous users to access the +<tt>Login</tt> page (anonymous users is specified by the <tt>?</tt> question mark). +We allow any users with role equal to "normal" (to be defined later) +to access all the pages, that is, the <tt>Login</tt> and <tt>Home</tt> pages. +Lastly, we deny all users without any roles to access any page. The authorization +rules are executed on first match basis. +</p> + +<p id="90088" class="block-content">If you now try to access the <tt>Home</tt> page by pointing your browser +to the <tt>index.php</tt> you will be redirected to the <tt>Login</tt> page. +</p> + +<h1 id="18011">Active Record for <tt>chat_users</tt> table</h1> +<p id="90089" class="block-content">The <com:DocLink ClassPath="System.Secutity.TUserManager" Text="TUserManager" /> +class only provides a read-only list of users. We need to be able to add or +login new users dynamically. So we need to create our own user manager class. +First, we shall setup a database with a <tt>chat_users</tt> table and create an ActiveRecord +that can work with the <tt>chat_users</tt> table with ease. For the demo, we +use <tt>sqlite</tt> as our database for ease of distributing the demo. The demo +can be extended to use other databases such as MySQL or Postgres SQL easily. +We define the <tt>chat_users</tt> table as follows. +<com:TTextHighlighter Language="text" CssClass="source block-content" id="code_90032"> +CREATE TABLE chat_users +( + username VARCHAR(20) NOT NULL PRIMARY KEY, + last_activity INTEGER NOT NULL DEFAULT "0" +); +</com:TTextHighlighter> +Next we define the corresponding <tt>ChatUserRecord</tt> class and save it as +<tt>chat/protected/App_Code/ChatUserRecord.php</tt> (you need to create the +<tt>App_Code</tt> directory as well). We also save the sqlite database file +as <tt>App_Code/chat.db</tt>. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90033"> +class ChatUserRecord extends TActiveRecord +{ + public $username; + public $last_activity; + + public static $_tablename='chat_users'; + + public static function finder() + { + return parent::getRecordFinder('ChatUserRecord'); + } +} +</com:TTextHighlighter> +Before using the <tt>ChatUserRecord</tt> class we to configure a default +database connection for ActiveRecord to function. In the <tt>chat/protected/application.xml</tt> +we import classes from the <tt>App_Code</tt> directory and add an +<a href="?page=Database.ActiveRecord">ActiveRecord configuration module</a>. +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90034"> +<?xml version="1.0" encoding="utf-8"?> +<application id="Chat" Mode="Debug"> + <paths> + <using namespace="Application.App_Code.*" /> + <using namespace="System.Data.*" /> + <using namespace="System.Data.ActiveRecord.*" /> + <using namespace="System.Security.*" /> + <using namespace="System.Web.UI.ActiveControls.*" /> + </paths> + <modules> + <module class="TActiveRecordConfig" EnableCache="true" + Database.ConnectionString="sqlite:protected/App_Code/chat.db" /> + </modules> +</application> +</com:TTextHighlighter> +</p> + +<h2 id="18020">Custom User Manager class</h2> +<p id="90090" class="block-content">To implement a custom user manager module class we just need +to extends the <tt>TModule</tt> class and implement the <tt>IUserManager</tt> +interface. The <tt>getGuestName()</tt>, <tt>getUser()</tt> and <tt>validateUser()</tt> +methods are required by the <tt>IUserManager</tt> interface. +We save the custom user manager class as <tt>App_Code/ChatUserManager.php</tt>. +</p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90035"> +class ChatUserManager extends TModule implements IUserManager +{ + public function getGuestName() + { + return 'Guest'; + } + + public function getUser($username=null) + { + $user=new TUser($this); + $user->setIsGuest(true); + if($username !== null && $this->usernameExists($username)) + { + $user->setIsGuest(false); + $user->setName($username); + $user->setRoles(array('normal')); + } + return $user; + } + + public function addNewUser($username) + { + $user = new ChatUserRecord(); + $user->username = $username; + $user->save(); + } + + public function usernameExists($username) + { + $finder = ChatUserRecord::finder(); + $record = $finder->findByUsername($username); + return $record instanceof ChatUserRecord; + } + + public function validateUser($username,$password) + { + return $this->usernameExists($username); + } +} +</com:TTextHighlighter> +<p id="90091" class="block-content"> +The <tt>getGuestName()</tt> +method simply returns the name for a guest user and is not used in our application. +The <tt>getUser()</tt> method returns a <tt>TUser</tt> object if the username +exists in the database, the <tt>TUser</tt> object is set with role of "normal" +that corresponds to the <tt><authorization></tt> rules defined in our +<tt>config.xml</tt> file. </p> + +<p id="90092" class="block-content">The <tt>addNewUser()</tt> and <tt>usernameExists()</tt> +method uses the ActiveRecord corresponding to the <tt>chat_users</tt> table to +add a new user and to check if a username already exists, respectively. +</p> + +<p id="90093" class="block-content">The next thing to do is change the <tt>config.xml</tt> configuration to use +our new custom user manager class. We simply change the <tt><module></tt> +configuration with <tt>id="users"</tt>.</p> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90036"> +<module id="users" class="ChatUserManager" /> +</com:TTextHighlighter> + +<h1 id="18012">Authentication</h1> +<p id="90094" class="block-content">To perform authentication, we just want the user to enter a unique +username. We add a +<com:DocLink ClassPath="System.Web.UI.WebControls.TCustomValidator" Text="TCustomValidator" /> +for validate the uniqueness of the username and add an <tt>OnClick</tt> event handler +for the login button.</p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90037"> +<com:TCustomValidator + ControlToValidate="username" + Display="Dynamic" + OnServerValidate="checkUsername" + ErrorMessage="The username is already taken." /> + +... + +<com:TButton Text="Login" OnClick="createNewUser" /> +</com:TTextHighlighter> +In the <tt>Login.php</tt> file, we add the following 2 methods. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90038"> +function checkUsername($sender, $param) +{ + $manager = $this->Application->Modules['users']; + if($manager->usernameExists($this->username->Text)) + $param->IsValid = false; +} + +function createNewUser($sender, $param) +{ + if($this->Page->IsValid) + { + $manager = $this->Application->Modules['users']; + $manager->addNewUser($this->username->Text); + + //do manual login + $user = $manager->getUser($this->username->Text); + $auth = $this->Application->Modules['auth']; + $auth->updateSessionUser($user); + $this->Application->User = $user; + + $url = $this->Service->constructUrl($this->Service->DefaultPage); + $this->Response->redirect($url); + } +} +</com:TTextHighlighter> +The <tt>checkUserName()</tt> method uses the <tt>ChatUserManager</tt> class +(recall that in the <tt>config.xml</tt> configuration we set the +ID of the custom user manager class as "users") to validate the username +is not taken. +</p> +<p id="90095" class="block-content"> +In the <tt>createNewUser</tt> method, when the validation passes (that is, +when the user name is not taken) we add a new user. Afterward we perform +a manual login process:</p> +<ul id="u2" class="block-content"> + <li>First we obtain a <tt>TUser</tt> instance from +our custom user manager class using the <tt>$manager->getUser(...)</tt> method.</li> + <li>Using the <tt>TAuthManager</tt> we set/update the user object in the + current session data.</li> + <li>Then we set/update the <tt>Application</tt>'s user instance with our + new user object.</li> +</ul> +</p> +<p id="finally" class="block-content"> +Finally, we redirect the client to the default <tt>Home</tt> page. +</p> + +<h2 id="18021">Default Values for ActiveRecord</h2> +<p id="90096" class="block-content">If you try to perform a login now, you will receive an error message like +"<i>Property '<tt>ChatUserRecord::$last_activity</tt>' must not be null as defined +by column '<tt>last_activity</tt>' in table '<tt>chat_users</tt>'.</i>". This means that the <tt>$last_activity</tt> +property value was null when we tried to insert a new record. We need to either +define a default value in the corresponding column in the table and allow null values or set the default +value in the <tt>ChatUserRecord</tt> class. We shall demonstrate the later by +altering the <tt>ChatUserRecord</tt> with the addition of a set getter/setter +methods for the <tt>last_activity</tt> property. + +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90039"> +private $_last_activity; + +public function getLast_Activity() +{ + if($this->_last_activity === null) + $this->_last_activity = time(); + return $this->_last_activity; +} + +public function setLast_Activity($value) +{ + $this->_last_activity = $value; +} +</com:TTextHighlighter> +Notice that we renamed <tt>$last_activity</tt> to <tt>$_last_activity</tt> (note +the underscore after the dollar sign). +</p> + +<h1 id="18013">Main Chat Application</h1> +<p id="90097" class="block-content">Now we are ready to build the main chat application. We use a simple +layout that consist of one panel holding the chat messages, one panel +to hold the users list, a textarea for the user to enter the text message +and a button to send the message. +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90040"> +<!doctype html public "-//W3C//DTD XHTML 1.0 Strict//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + <title>Prado Chat Demo</title> +<style> +.messages +{ + width: 500px; + height: 300px; + float: left; + border: 1px solid ButtonFace; + overflow: auto; +} +.user-list +{ + margin-left: 2px; + float: left; + width: 180px; + height: 300px; + border: 1px solid ButtonFace; + overflow: auto; + font-size: 0.85em; +} +.message-input +{ + float: left; +} + +.message-input textarea +{ + margin-top: 3px; + padding: 0.4em 0.2em; + width: 493px; + font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; + font-size: 0.85em; + height: 40px; +} +.send-button +{ + margin: 0.5em; +} +</style> +</head> +<body> +<com:TForm> +<h1 id="18014">Prado Chat Demo</h1> +<div id="messages" class="messages"> + <com:TPlaceHolder ID="messageList" /> +</div> +<div id="users" class="user-list"> + <com:TPlaceHolder ID="userList" /> +</div> +<div class="message-input"> + <com:TActiveTextBox ID="userinput" + Columns="40" Rows="2" TextMode="MultiLine" /> + <com:TActiveButton ID="sendButton" CssClass="send-button" + Text="Send" /> +</div> +</com:TForm> +<com:TJavascriptLogger /> +</body> +</html> +</com:TTextHighlighter> +We added two Active Control components: a +<com:DocLink ClassPath="System.Web.UI.ActiveControls.TActiveTextBox" Text="TActiveTextBox" /> +and a +<com:DocLink ClassPath="System.Web.UI.ActiveControls.TActiveButton" Text="TActiveButton" />. +We also added a +<com:DocLink ClassPath="System.Web.UI.WebControls.TJavascriptLogger" Text="TJavascriptLogger" /> +that will be very useful for understanding how the Active Controls work. +</p> + +<h2 id="18022">Exploring the Active Controls</h2> +<p id="90098" class="block-content">We should have some fun before we proceeding with setting up the chat buffering. We want +to see how we can update the current page when we receive a message. First, we add +an <tt>OnClick</tt> event handler for the <tt>Send</tt> button. + +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90041"> +<com:TActiveButton ID="sendButton" CssClass="send-button" + Text="Send" OnClick="processMessage"/> +</com:TTextHighlighter> +And the corresponding event handler method in the <tt>Home.php</tt> class (we +need to create this new file too). +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90042"> +class Home extends TPage +{ + function processMessage($sender, $param) + { + echo $this->userinput->Text; + } +} +</com:TTextHighlighter> +If you now type something in the main application textbox and click the send button +you should see whatever you have typed echoed in the <tt>TJavascriptLogger</tt> console. +</p> + +<p id="90099" class="block-content">To append or add some content to the message list panel, we need to use +some methods in the +<com:DocLink ClassPath="System.Web.UI.ActiveControls.TCallbackClientScript" Text="TCallbackClientScript" /> +class which is available through the <tt>CallbackClient</tt> property of the +current <tt>TPage</tt> object. For example, we do can do +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90043"> +function processMessage($sender, $param) +{ + $this->CallbackClient->appendContent("messages", $this->userinput->Text); +} +</com:TTextHighlighter> +This is one way to update some part of the existing page during a callback (AJAX style events) +and will be the primary way we will use to implement the chat application. +</p> + +<h1 id="18015">Active Record for <tt>chat_buffer</tt> table</h1> +<p id="90100" class="block-content">To send a message to all the connected users we need to buffer or store +the message for each user. We can use the database to buffer the messages. The +<tt>chat_buffer</tt> table is defined as follows. +<com:TTextHighlighter Language="text" CssClass="source block-content" id="code_90044"> +CREATE TABLE chat_buffer +( + id INTEGER PRIMARY KEY, + for_user VARCHAR(20) NOT NULL, + from_user VARCHAR(20) NOT NULL, + message TEXT NOT NULL, + created_on INTEGER NOT NULL DEFAULT "0" +); +</com:TTextHighlighter> +The corresponding <tt>ChatBufferRecord</tt> class is saved as +<tt>App_Code/ChatBufferRecord.php</tt>. + +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90045"> +class ChatBufferRecord extends TActiveRecord +{ + public $id; + public $for_user; + public $from_user; + public $message; + private $_created_on; + + public static $_tablename='chat_buffer'; + + public function getCreated_On() + { + if($this->_created_on === null) + $this->_created_on = time(); + return $this->_created_on; + } + + public function setCreated_On($value) + { + $this->_created_on = $value; + } + + public static function finder() + { + return parent::getRecordFinder('ChatBufferRecord'); + } +} +</com:TTextHighlighter> +</p> + +<h1 id="18016">Chat Application Logic</h1> +<p id="90101" class="block-content">We finally arrive at the guts of the chat application logic. First, we +need to save a received message into the chat buffer for <b>all</b> the +current users. We add this logic in the <tt>ChatBufferRecord</tt> class. + +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90046"> +public function saveMessage() +{ + foreach(ChatUserRecord::finder()->findAll() as $user) + { + $message = new self; + $message->for_user = $user->username; + $message->from_user = $this->from_user; + $message->message = $this->message; + $message->save(); + if($user->username == $this->from_user) + { + $user->last_activity = time(); //update the last activity; + $user->save(); + } + } +} +</com:TTextHighlighter> +We first find all the current users using the <tt>ChatUserRecord</tt> finder +methods. Then we duplicate the message and save it into the database. In addition, +we update the message sender's last activity timestamp. The above piece of code +demonstrates the simplicity and succinctness of using ActiveRecords for simple database designs. +</p> + +<p id="90102" class="block-content">The next piece of the logic is to retrieve the users' messages from the buffer. +We simply load all the messages for a particular username and format that message +appropriately (remember to escape the output to prevent Cross-Site Scripting attacks). +After we load the messages, we delete those loaded messages and any older +messages that may have been left in the buffer. +</p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90047"> +public function getUserMessages($user) +{ + $content = ''; + foreach($this->findAll('for_user = ?', $user) as $message) + $content .= $this->formatMessage($message); + $this->deleteAll('for_user = ? OR created_on < ?',
+ $user, time() - 300); //5 min inactivity + return $content; +} + +protected function formatMessage($message) +{ + $user = htmlspecialchars($message->from_user); + $content = htmlspecialchars($message->message); + return "<div class=\"message\"><strong>{$user}:</strong>"
+ ." <span>{$content}</span></div>"; +} +</com:TTextHighlighter> + +To retrieve a list of current users (formatted), we add this logic to the +<tt>ChatUserRecord</tt> class. We delete any users that may have been inactive +for awhile. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90048"> +public function getUserList() +{ + $this->deleteAll('last_activity < ?', time()-300); //5 min inactivity + $content = '<ul>'; + foreach($this->findAll() as $user) + $content .= '<li>'.htmlspecialchars($user->username).'</li>'; + $content .= '</ul>'; + return $content; +} +</com:TTextHighlighter> + +<div class="note"><b class="tip">Note:</b> +For simplicity +we formatted the messages in these Active Record classes. For large applications, +these message formatting tasks should be done using Prado components (e.g. using +a TRepeater in the template or a custom component). +</div> +</p> + +<h1 id="18017">Putting It Together</h1> +<p id="90103" class="block-content">Now comes to put the application flow together. In the <tt>Home.php</tt> we update +the <tt>Send</tt> buttons <tt>OnClick</tt> event handler to use the application +logic we just implemented. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90049"> +function processMessage($sender, $param) +{ + if(strlen($this->userinput->Text) > 0) + { + $record = new ChatBufferRecord(); + $record->message = $this->userinput->Text; + $record->from_user = $this->Application->User->Name; + $record->saveMessage(); + + $this->userinput->Text = ''; + $messages = $record->getUserMessages($this->Application->User->Name); + $this->CallbackClient->appendContent("messages", $messages); + $this->CallbackClient->focus($this->userinput); + } +} +</com:TTextHighlighter> +We simply save the message to the chat buffer and then ask for all the messages +for the current user and update the client side message list using a callback +response (AJAX style). +</p> + +<p id="90104" class="block-content">At this point the application is actually already functional, just not very +user friendly. If you open two different browsers, you should be able to communicate +between the two users whenever the <tt>Send</tt> button is clicked. +</p> + +<p id="90105" class="block-content">The next part is perhaps the more tricker and fiddly than the other tasks. We +need to improve the user experience. First, we want a list of current users +as well. So we add the following method to <tt>Home.php</tt>, we can call +this method when ever some callback event is raised, e.g. when the <tt>Send</tt> +button is clicked. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90050"> +protected function refreshUserList() +{ + $lastUpdate = $this->getViewState('userList',''); + $users = ChatUserRecord::finder()->getUserList(); + if($lastUpdate != $users) + { + $this->CallbackClient->update('users', $users); + $this->setViewstate('userList', $users); + } +} +</com:TTextHighlighter> +</p> + +<p id="90106" class="block-content">Actually, we want to periodically update the messages and user list as new +users join in and new message may arrive from other users. So we need to refresh +the message list as well.</p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90051"> +function processMessage($sender, $param) +{ + ... + $this->refreshUserList(); + $this->refreshMessageList(); + ... +} + +protected function refreshMessageList() +{ + //refresh the message list + $finder = ChatBufferRecord::finder(); + $content = $finder->getUserMessages($this->Application->User->Name); + if(strlen($content) > 0) + { + $anchor = (string)time(); + $content .= "<a href=\"#\" id=\"{$anchor}\"> </a>"; + $this->CallbackClient->appendContent("messages", $content); + $this->CallbackClient->focus($anchor); + } +} +</com:TTextHighlighter> +The anchor using <tt>time()</tt> as ID for a focus point is so that when the +message list on the client side gets very long, the focus method will +scroll the message list to the latest message (well, it works in most browsers). +</p> + +<p id="90107" class="block-content">Next, we need to redirect the user back to the login page if the user has +been inactive for some time, say about 5 mins, we can add this check to any stage +of the page life-cycle. Lets add it to the <tt>onLoad()</tt> stage. +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90052"> +public function onLoad($param) +{ + $username = $this->Application->User->Name; + if(!$this->Application->Modules['users']->usernameExists($username)) + { + $auth = $this->Application->Modules['auth']; + $auth->logout(); + + //redirect to login page. + $this->Response->Redirect($this->Service->ConstructUrl($auth->LoginPage)); + } +} +</com:TTextHighlighter> +</p> + +<h1 id="18018">Improving User Experience</h1> +<p id="90108" class="block-content">The last few details are to periodically check for new messages and +refresh the user list. We can accomplish this by polling the server using a +<com:DocLink ClassPath="System.Web.UI.ActiveControls.TTimeTriggeredCallback" Text="TTimeTriggeredCallback" /> +control. We add a <tt>TTimeTriggeredCallback</tt> to the <tt>Home.page</tt> +and call the <tt>refresh</tt> handler method defined in <tt>Home.php</tt>. +We set the polling interval to 2 seconds. +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90053"> +<com:TTimeTriggeredCallback OnCallback="refresh" + Interval="2" StartTimerOnLoad="true" /> +</com:TTextHighlighter> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90054"> +function refresh($sender, $param) +{ + $this->refreshUserList(); + $this->refreshMessageList(); +} +</com:TTextHighlighter> +</p> + +<p id="90109" class="block-content">The final piece requires us to use some javascript. We want that when the +user type some text in the textarea and press the <tt>Enter</tt> key, we want it +to send the message without clicking on the <tt>Send</tt> button. We add to the +<tt>Home.page</tt> some javascript. + +<com:TTextHighlighter Language="javascript" CssClass="source block-content" id="code_90055"> +<com:TClientScript> +Event.observe($("<%= $this->userinput->ClientID %>"), "keypress", function(ev) +{ + if(Event.keyCode(ev) == Event.KEY_RETURN) + { + if(Event.element(ev).value.length > 0) + new Prado.Callback("<%= $this->sendButton->UniqueID %>"); + Event.stop(ev); + } +}); +</com:TClientScript> +</com:TTextHighlighter> +Details regarding the javascript can be explored in the +<a href="?page=Advanced.Scripts">Introduction to Javascript</a> section of the quickstart. +</p> + +<p id="90110" class="block-content">This completes the tutorial on making a basic chat web application using +the Prado framework. Hope you have enjoyed it. +</p> + +<div class="last-modified">$Id: AjaxChat.page 1650 2007-01-24 06:55:32Z wei $</div></com:TContent>
\ No newline at end of file diff --git a/demos/quickstart/protected/pages/Tutorial/fr/CurrencyConverter.page b/demos/quickstart/protected/pages/Tutorial/fr/CurrencyConverter.page new file mode 100644 index 00000000..071a13d7 --- /dev/null +++ b/demos/quickstart/protected/pages/Tutorial/fr/CurrencyConverter.page @@ -0,0 +1,405 @@ +<com:TContent ID="body"> + <h1 id="16001">Building a Simple Currency Converter</h1> + <p id="80053" class="block-content">This tutorial introduces the Prado web application framework and teaches + you how to build a simple web application in a few simple steps. This + tutorial assumes that you are familiar with PHP and you have access + to a web server that is able to serve PHP5 scripts. + </p> + + <p id="80054" class="block-content">In this tutorial you will build a simple web application that converts + a dollar amount to an other currency, given the rate of that currency + relative to the dollar. The completed application is shown bellow. + <img src=<%~ example2.png %> class="figure" /> + You can try the application <a href="../currency-converter/index.php">locally</a> or at + <a href="http://www.pradosoft.com/demos/currency-converter/">Pradosoft.com</a>. + Notice that the application still functions exactly the same if javascript + is not available on the user's browser. + </p> + + <h1 id="download">Downloading and Installing Prado</h1> + <p id="80055" class="block-content">To install Prado, simply download the latest version of Prado from + <a href="http://www.pradosoft.com/">http://www.pradosoft.com</a> + and unzip the file to a directory <b>not</b> accessible by your web server + (you may unzip it to a directory accessible by the web server if you wish + to see the demos and test). For further detailed installation, see the + <a href="?page=GettingStarted.Installation">Quickstart Installation</a> guide. + </p> + + <h1 id="16002">Creating a new Prado web Application</h1> + <p id="80056" class="block-content">The quickest and simplest way to create a new Prado web application is + to use the command tool <tt>prado-cli.php</tt> found in the <tt>framework</tt> + directory of the Prado distribution. We create a new application by running + the following command in your + command prompt or console. The command creates a new directory named + <tt>currency-converter</tt> in your current working directory. + You may need to change to the appropriate directory + first. + See the <a href="?page=GettingStarted.CommandLine">Command Line Tool</a>
+ for more details.
+ </p>
+<com:TTextHighlighter Language="text" CssClass="source block-content" id="code111"> +php prado/framework/prado-cli.php -c currency-converter +</com:TTextHighlighter> + + <p id="80057" class="block-content">The above command creates the necessary directory structure and minimal + files (including "index.php" and "Home.page") to run a Prado web application. + Now you can point your browser's url to the web server to serve up + the <tt>index.php</tt> script in the <tt>currency-converter</tt> directory. + You should see the message "Welcome to Prado!" + </p> + + <h1 id="16003">Creating the Currency Converter User Interface</h1> + <p id="80058" class="block-content">We start by editing the <tt>Home.page</tt> file found in the + <tt>currency-converter/protected/pages/</tt> directory. Files ending + with ".page" are page templates that contains HTML and Prado controls. + We simply add two textboxes, three labels and one button as follows.
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="form1"> +<com:TForm> + <fieldset> + <legend>Currency Converter</legend> + <div class="rate-field"> + <com:TLabel ForControl="currencyRate" Text="Exchange Rate per $1:" /> + <com:TTextBox ID="currencyRate" /> + </div> + <div class="dollar-field"> + <com:TLabel ForControl="dollars" Text="Dollars to Convert:" /> + <com:TTextBox ID="dollars" /> + </div> + <div class="total-field"> + <span class="total-label">Amount in Other Currency:</span> + <com:TLabel ID="total" CssClass="result" /> + </div> + <div class="convert-button"> + <com:TButton Text="Convert" /> + </div> + </fieldset> +</com:TForm> +</com:TTextHighlighter>
+ <p id="refresh" class="block-content"> + If you refresh the page, you should see something similar to the following figure. + It may not look very pretty or orderly, but we shall change that later using CSS. + <img src=<%~ example1.png %> class="figure" /> + </p> + + <p id="80059" class="block-content"> + The first component we add is a + <com:DocLink ClassPath="System.Web.UI.TForm" Text="TForm" /> + that basically corresponds to the HTML <tt><form></tt> element. + In Prado, only <b>one</b> <tt>TForm</tt> element is allowed per page. + </p> + + <p id="80060" class="block-content">The next two pair of component we add is the + <com:DocLink ClassPath="System.Web.UI.WebControls.TLabel" Text="TLabel" /> + and + <com:DocLink ClassPath="System.Web.UI.WebControls.TTextBox" Text="TTextBox" /> + that basically defines a label and a textbox for the user of the application + to enter the currency exchange rate. + The <tt>ForControl</tt> property value determines which component + that the label is for. This allows the user of the application to click + on the label to focus on the field (a good thing). You could have used + a plain HTML <tt><label></tt> element to do the same thing, but + you would have to find the correct <tt>ID</tt> of the textbox (or + <tt><input></tt> in HTML) as Prado components may/will render the + <tt>ID</tt> value differently in the HTML output. + </p> + + <p id="80061" class="block-content">The next pair of components are similar and defines the textbox + to hold the dollar value to be converted. + The <tt>TLabel</tt> with <tt>ID</tt> value "total" defines a simple label. + Notice that the <tt>ForControl</tt> property is absent. This means that this + label is simply a simple label which we are going to use to display the + converted total amount. + </p> + + <p id="80062" class="block-content">The final component is a + <com:DocLink ClassPath="System.Web.UI.WebControls.TButton" Text="TButton" /> + that the user will click to calculate the results. The <tt>Text</tt> + property sets the button label. + </p> + + <h1 id="16004">Implementing Currency Conversion</h1> + + <p id="80063" class="block-content">If you tried clicking on the "Convert" button then the page will refresh + and does not do anything else. For the button to do some work, we need + to add a "Home.php" to where "Home.page" is. The <tt>Home</tt> class + should extends the + <com:DocLink ClassPath="System.Web.UI.TPage" Text="TPage" />, the default base + class for all Prado pages.
+ </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code3"> +<?php +class Home extends TPage +{ + +} +?> +</com:TTextHighlighter>
+ <p id="1111" class="block-content"> + Prado uses PHP's <tt>__autoload</tt> method to load classes. The convention + is to use the class name with ".php" extension as filename. + </p> + + <p id="80064" class="block-content">So far there is nothing interesting about Prado, we just declared some + "web components" in some template file named Home.page and created + a "Home.php" file with a <tt>Home</tt> class. The more interesting + bits are in Prado's event-driven architecture as we shall see next. + </p> + + <p id="80065" class="block-content">We want that when the user click on the "Convert" button, we take the + values in the textbox, do some calculation and present the user with + the converted total. To handle the user clicking of the "Convert" button + we simply add an <tt>OnClick</tt> property to the "Convert" button in + the "Home.page" template and add a corresponding event handler method + in the "Home.php".
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code4"> +<com:TButton Text="Convert" OnClick="convert_clicked" /> +</com:TTextHighlighter> + <p id="222" class="block-content">
+ The value of the <tt>OnClick</tt>, "<tt>convert_clicked</tt>", will be the method + name in the "Home.php" that will called when the user clicks on the + "Convert" button.
+ </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code5"> +class Home extends TPage +{ + public function convert_clicked($sender, $param) + { + $rate = floatval($this->currencyRate->Text); + $dollars = floatval($this->dollars->Text); + $this->total->Text = $rate * $dollars; + } +} +</com:TTextHighlighter>
+<div id="3332" class="block-content">
+ <p id="333"> + If you run the application in your web browser, enter some values and click + the "Convert" button then you should see that calculated value displayed next + to the "Amount in Other Currency" label. + </p> + + <p id="80066">In the "<tt>convert_clicked</tt>" method the first parameter, <tt>$sender</tt>, + corresponds to the object that raised the event, in this case, + the "Convert" button. The second parameter, <tt>$param</tt> contains + any additional data that the <tt>$sender</tt> object may wish to have added. + </p> + + <p id="80067">We shall now examine, the three lines that implements the simply currency + conversion in the "<tt>convert_clicked</tt>" method.
+ </p>
+</div> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code6" > +$rate = floatval($this->currencyRate->Text); +</com:TTextHighlighter>
+ <p id="444" class="block-content"> + The statement <tt>$this->currencyRate</tt> corresponds to the + <tt>TTextBox</tt> component with <tt>ID</tt> value "currencyRate" in the + "Home.page" template. The <tt>Text</tt> property of the <tt>TTextBox</tt> + contains the value that the user entered. So, we obtain this + value by <tt>$this->currencyRate->Text</tt> which we convert the + value to a float value.
+ </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code7"> +$dollars = floatval($this->dollars->Text); +</com:TTextHighlighter>
+<div id="5551" class="block-content">
+ <p id="555"> + The next line does a similar things, it takes the user value from + the <tt>TTextBox</tt> with <tt>ID</tt> value "dollars and converts it to + a float value. + </p> + + <p id="80068">The third line calculates the new amount and set this value in the + <tt>Text</tt> property of the <tt>TLabel</tt> with <tt>ID="total"</tt>. + Thus, we display the new amount to the user in the label.
+ </p> +</div>
+<com:TTextHighlighter Language="php" CssClass="source block-content" id="code8"> +$this->total->Text = $rate * $dollars; +</com:TTextHighlighter> + + <h1 id="16005">Adding Validation</h1> + <p id="80069" class="block-content">The way we convert the user entered value to float ensures that the + total amount is always a number. So the user is free to enter what + ever they like, they could even enter letters. The user's experience + in using the application can be improved by adding validators + to inform the user of the allowed values in the currency rate and the + amount to be calcuated. + </p> + + <p id="80070">For the currency rate, we should ensure that</p> + <ol id="o111" class="block-content"> + <li>the user enters a value,</li> + <li>the currency rate is a valid number,</li> + <li>the currency rate is positive.</li> + </ol>
+ <p id="666" class="block-content"> + To ensure 1 we add one + <com:DocLink ClassPath="System.Web.UI.WebControls.TRequiredFieldValidator" Text="TRequiredFieldValidator" />. To ensure 2 and 3, we add one + <com:DocLink ClassPath="System.Web.UI.WebControls.TCompareValidator" Text="TCompareValidator" />. We may add these validators any where within + the "Home.page" template. Further details regarding these validator and other + validators can be found in the + <a href="?page=Controls.Validation">Validation Controls</a> page.
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code9"> +<com:TRequiredFieldValidator + ControlToValidate="currencyRate" + ErrorMessage="Please enter a currency rate." /> +<com:TCompareValidator + ControlToValidate="currencyRate" + DataType="Float" + ValueToCompare="0" + Operator="GreaterThan" + ErrorMessage="Please enter a positive currency rate." /> +</com:TTextHighlighter> + + <p id="80071" >For the amount to be calculated, we should ensure that</p> + <ol id="o222" class="block-content"> + <li>the user enters a value,</li> + <li>the value is a valid number (not including any currency or dollar signs).</li> + </ol>
+ <p id="777" class="block-content"> + To ensure 1 we just add another <tt>TRequiredFieldValidator</tt>, for 2 + we could use a + <com:DocLink ClassPath="System.Web.UI.WebControls.TDataTypeValidator" Text="TDataTypeValidator" />. For simplicity we only allow the user to enter + a number for the amount they wish to convert.
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code9a"> +<com:TRequiredFieldValidator + ControlToValidate="dollars" + ErrorMessage="Please enter the amount you wish to calculate." /> +<com:TDataTypeValidator + ControlToValidate="dollars" + DataType="Float" + ErrorMessage="Please enter a number." /> +</com:TTextHighlighter> + </p> + + <p id="80072" class="block-content">Now if you try to enter some invalid data in the application or left out + any of the fields the validators will be activated and present the user + with error messages. Notice that the error messages are presented + without reloading the page. Prado's validators by default validates + using both javascript and server side. The server side validation + is <b>always performed</b>. For the server side, we + should skip the calculation if the validators are not satisfied. This can + done as follows.
+ </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code10" > +public function convert_clicked($sender, $param) +{ + if($this->Page->IsValid) + { + $rate = floatval($this->currencyRate->Text); + $dollars = floatval($this->dollars->Text); + $this->total->Text = $rate * $dollars; + } +} +</com:TTextHighlighter> + + <h1 id="16006">Improve User Experience With Active Controls</h1> + <p id="80073" class="block-content">In this simple application we may further improve the user experience + by increasing the responsiveness of the application. One way to achieve + a faster response is calculate and present the results without reloading + the whole page. + </p> + + <p id="80074" class="block-content">We can replace the <tt>TButton</tt> with the Active Control counter part, + <com:DocLink ClassPath="System.Web.UI.ActiveControls.TActiveButton" Text="TActiveButton" />, + that can trigger a server side click event without reloading the page. + In addition, we can change the "totals" <tt>TLabel</tt> with the + Active Control counter part, + <com:DocLink ClassPath="System.Web.UI.ActiveControls.TActiveLabel" Text="TActiveLabel" />, such that the server side can update the browser without + reloading the page.
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code11"> +<div class="total-field"> + <span class="total-label">Amount in Other Currency:</span> + <com:TActiveLabel ID="total" CssClass="result" /> + </div> + <div class="convert-button"> + <com:TActiveButton Text="Convert" OnClick="convert_clicked" /> +</div> +</com:TTextHighlighter>
+ <p id="1232" class="block-content"> + The server side logic remains the same, we just need to import the + Active Controls name space as they are not included by default. We + add the following line to the begin of "Home.php".
+ </p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code12"> +Prado::using('System.Web.UI.ActiveControls.*'); +</com:TTextHighlighter> + + <p id="80075" class="block-content">If you try the application now, you may notice that the page no longer + needs to reload to calculate and display the converted total amount. + However, since there is not page reload, there is no indication or not obvious + that by clicking on the "Convert" button any has happened. + We can further refine the user experience by change the text of "total" label + to "calculating..." when the user clicks on the "Convert" button. The text of + the "total" label will still be updated with the new calculate amount as before. + </p> + + <p id="80076" class="block-content">To indicate that the calculation is in progress, we can change the text + of the "total" label as follows. We add a <tt>ClientSide.OnLoading</tt> property + to the "Convert" button (since this button is responsible for requesting + the calculation).
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code13"> +<com:TActiveButton Text="Convert" OnClick="convert_clicked" > + <prop:ClientSide.OnLoading> + $('<%= $this->total->ClientID %>').innerHTML = "calculating..." + </prop:ClientSide.OnLoading> +</com:TActiveButton> +</com:TTextHighlighter> + + <p id="80077" class="block-content">The <tt>ClientSide.OnLoading</tt> and various + <com:DocLink ClassPath="System.Web.UI.ActiveControls.TCallbackClientSide" Text="other properties" /> accept a javascript block as their content or value. + The javascript code <tt>$('...')</tt> is a javascript function that is + equivalent to <tt>document.getElementById('...')</tt> that takes a string + with the ID of an HTML element. Since Prado renders its components's IDs, we need + to use the rendered ID of the "total" label, that is, <tt>$this->total->ClientID</tt>. We place this bit of code within a <tt><%= %></tt> to obtain the rendered HTML ID for the "total" label. The rest of the + javascript code <tt>innerHTML = "calculating..."</tt> simply changes + the content of the "total" label. + </p> + + <h1 id="16007">Adding Final Touches</h1> + <p id="80078" class="block-content">So far we have built a simple currency converter web application with + little attention of the looks and feel. Now we can add a stylesheet + to improve the overall appearance of the application. We can simply + add the stylesheet inline with the template code or we may create + a "theme". + </p> + + <p id="80079" class="block-content">To create and use a theme with Prado applications, we simply create a new + directory "themes/Basic" in the <tt>currency-converter</tt> directory. + You may need to create the <tt>themes</tt> directory first. Any + directory within the <tt>themes</tt> are considered as a theme with the + name of the theme being the directory name. See the + <a href="?page=Advanced.Themes">Themes and Skins</a> for further details. + </p> + + <p id="80080" class="block-content">We simply create a CSS file named "common.css" and save it in the + <tt>themes/Basic</tt> directory. Then we add the following code + to the beginning of "Home.page" (we add a little more HTML as well).
+ </p> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code14"> +<%@ Theme="Basic" %> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" +"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" > +<com:THead Title="Currency Converter" /> +<body> +</com:TTextHighlighter>
+ <p id="4334" class="block-content"> + The first line <tt><%@ Theme="Basic" %></tt> defines the + theme to be used for this page. The + <com:DocLink ClassPath="System.Web.UI.WebControls.THead" Text="THead" /> + corresponds to the HTML <tt><head></tt> element. In addition + to display the <tt>Title</tt> property by the <tt>THead</tt>, all CSS + files in the <tt>themes/Basic</tt> directory are also rendered/linked + for the current page. Our final currency converter web application + looks like the following. + <img src=<%~ example2.png %> class="figure" /> + This completes introduction tutorial to the Prado web application framework. + </p> +<div class="last-modified">$Id: CurrencyConverter.page 1654 2007-01-25 07:24:40Z wei $</div></com:TContent>
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