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1 files changed, 134 insertions, 130 deletions
diff --git a/demos/quickstart/protected/pages/Tutorial/AjaxChat.page b/demos/quickstart/protected/pages/Tutorial/AjaxChat.page index 2d49c9f6..ec6fc149 100644 --- a/demos/quickstart/protected/pages/Tutorial/AjaxChat.page +++ b/demos/quickstart/protected/pages/Tutorial/AjaxChat.page @@ -1,67 +1,67 @@ <com:TContent ID="body"> - <h1>Building an AJAX Chat Application</h1> - <p>This tutorial introduces the Prado web application framework's + <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 + 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. - <ul> + </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> - <p>In this tutorial you will build an AJAX Chat web application that allows - multiple users to communicate through their web browser. + <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 + 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. + The main application chat page is shown bellow. <img src=<%~ chat1.png %> class="figure" /> </p> - <h1>Download, Install and Create a New Application</h1> - <p>The download and installation steps are similar to those in + <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> + See the <a href="?page=GettingStarted.CommandLine">Command Line Tool</a> for more details. -<com:TTextHighlighter Language="text" CssClass="source"> +<com:TTextHighlighter Language="text" CssClass="source block-content" id="code_90027"> php prado/framework/prado-cli.php -c chat -</com:TTextHighlighter> +</com:TTextHighlighter> </p> - <p>The above command creates the necessary directory structure and minimal + <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!" + You should see the message "Welcome to Prado!" </p> - <h1>Authentication and Authorization</h1> - <p>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) + <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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90028"> <?php class Login extends TPage { } ?> </com:TTextHighlighter> -<com:TTextHighlighter Language="prado" CssClass="source"> -<!doctype html public "-//W3C//DTD XHTML 1.0 Strict//EN" +<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> @@ -87,7 +87,7 @@ class Login extends TPage </body> </html> </com:TTextHighlighter> - <p>The login page contains + <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" /> @@ -99,12 +99,12 @@ class Login extends TPage 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>Securing the <tt>Home</tt> page</h2> -<p>Now we wish that if the user is trying to access the main application +<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"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90030"> <?xml version="1.0" encoding="utf-8"?> <application id="Chat" Mode="Debug"> <paths> @@ -117,7 +117,7 @@ file to import some classes that we shall use later. </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"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90031"> <?xml version="1.0" encoding="utf-8"?> <configuration> <modules> @@ -131,41 +131,41 @@ secure the <tt>pages</tt> directory. </authorization> </configuration> </com:TTextHighlighter> -We setup the authentication using the default classes as explained in the +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 +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) +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>If you now try to access the <tt>Home</tt> page by pointing your browser +<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>Active Record for <tt>chat_users</tt> table</h1> -<p>The <com:DocLink ClassPath="System.Secutity.TUserManager" Text="TUserManager" /> +<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 +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"> -CREATE TABLE chat_users -( - username VARCHAR(20) NOT NULL PRIMARY KEY, - last_activity INTEGER NOT NULL DEFAULT "0" +<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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90033"> class ChatUserRecord extends TActiveRecord { public $username; @@ -181,9 +181,9 @@ class ChatUserRecord extends TActiveRecord </com:TTextHighlighter> Before using the <tt>ChatUserRecord</tt> class we to configure a default database connection for ActiveRecord to function. In the <tt>chat/protected/application.xml</tt> -we import classes from the <tt>App_Code</tt> directory and add an +we import classes from the <tt>App_Code</tt> directory and add an <a href="?page=Database.ActiveRecord">ActiveRecord configuration module</a>. -<com:TTextHighlighter Language="xml" CssClass="source"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90034"> <?xml version="1.0" encoding="utf-8"?> <application id="Chat" Mode="Debug"> <paths> @@ -201,14 +201,14 @@ we import classes from the <tt>App_Code</tt> directory and add an </com:TTextHighlighter> </p> -<h2>Custom User Manager class</h2> -<p>To implement a custom user manager module class we just need +<h2 id="18020">Custom User Manager class</h2> +<p id="90090" class="block-content">To implement a custom user manager module class we just need to extends the <tt>TModule</tt> class and implement the <tt>IUserManager</tt> interface. The <tt>getGuestName()</tt>, <tt>getUser()</tt> and <tt>validateUser()</tt> methods are required by the <tt>IUserManager</tt> interface. We save the custom user manager class as <tt>App_Code/ChatUserManager.php</tt>. -</p> -<com:TTextHighlighter Language="php" CssClass="source"> +</p> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90035"> class ChatUserManager extends TModule implements IUserManager { public function getGuestName() @@ -219,7 +219,7 @@ class ChatUserManager extends TModule implements IUserManager public function getUser($username=null) { $user=new TUser($this); - $user->setIsGuest(true); + $user->setIsGuest(true); if($username !== null && $this->usernameExists($username)) { $user->setIsGuest(false); @@ -228,7 +228,7 @@ class ChatUserManager extends TModule implements IUserManager } return $user; } - + public function addNewUser($username) { $user = new ChatUserRecord(); @@ -249,7 +249,7 @@ class ChatUserManager extends TModule implements IUserManager } } </com:TTextHighlighter> -<p> +<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 @@ -257,25 +257,25 @@ 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>The <tt>addNewUser()</tt> and <tt>usernameExists()</tt> -method uses the ActiveRecord corresponding to the <tt>chat_users</tt> table to +<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>The next thing to do is change the <tt>config.xml</tt> configuration to use +<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"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_90036"> <module id="users" class="ChatUserManager" /> </com:TTextHighlighter> -<h1>Authentication</h1> -<p>To perform authentication, we just want the user to enter a unique -username. We add a +<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"> +<com:TTextHighlighter Language="prado" CssClass="source block-content" id="code_90037"> <com:TCustomValidator ControlToValidate="username" Display="Dynamic" @@ -287,7 +287,7 @@ for the login button.</p> <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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90038"> function checkUsername($sender, $param) { $manager = $this->Application->Modules['users']; @@ -301,7 +301,7 @@ function createNewUser($sender, $param) { $manager = $this->Application->Modules['users']; $manager->addNewUser($this->username->Text); - + //do manual login $user = $manager->getUser($this->username->Text); $auth = $this->Application->Modules['auth']; @@ -314,15 +314,15 @@ function createNewUser($sender, $param) } </com:TTextHighlighter> The <tt>checkUserName()</tt> method uses the <tt>ChatUserManager</tt> class -(recall that in the <tt>config.xml</tt> configuration we set the +(recall that in the <tt>config.xml</tt> configuration we set the ID of the custom user manager class as "users") to validate the username is not taken. </p> -<p> -In the <tt>createNewUser</tt> method, when the validation passes (that is, +<p id="90095" class="block-content"> +In the <tt>createNewUser</tt> method, when the validation passes (that is, when the user name is not taken) we add a new user. Afterward we perform -a manual login process: -<ul> +a manual login process:</p> +<ul id="u2" class="block-content"> <li>First we obtain a <tt>TUser</tt> instance from our custom user manager class using the <tt>$manager->getUser(...)</tt> method.</li> <li>Using the <tt>TAuthManager</tt> we set/update the user object in the @@ -330,20 +330,22 @@ our custom user manager class using the <tt>$manager->getUser(...)</tt> method.< <li>Then we set/update the <tt>Application</tt>'s user instance with our new user object.</li> </ul> +</p> +<p id="finally" class="block-content"> Finally, we redirect the client to the default <tt>Home</tt> page. </p> -<h2>Default Values for ActiveRecord</h2> -<p>If you try to perform a login now, you will receive an error message like -"<i>Property '<tt>ChatUserRecord::$last_activity</tt>' must not be null as defined +<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 +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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90039"> private $_last_activity; public function getLast_Activity() @@ -362,13 +364,13 @@ Notice that we renamed <tt>$last_activity</tt> to <tt>$_last_activity</tt> (note the underscore after the dollar sign). </p> -<h1>Main Chat Application</h1> -<p>Now we are ready to build the main chat application. We use a simple +<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"> -<!doctype html public "-//W3C//DTD XHTML 1.0 Strict//EN" +<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> @@ -378,7 +380,7 @@ and a button to send the message. { width: 500px; height: 300px; - float: left; + float: left; border: 1px solid ButtonFace; overflow: auto; } @@ -400,7 +402,7 @@ and a button to send the message. .message-input textarea { margin-top: 3px; - padding: 0.4em 0.2em; + padding: 0.4em 0.2em; width: 493px; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 0.85em; @@ -414,7 +416,7 @@ and a button to send the message. </head> <body> <com:TForm> -<h1>Prado Chat Demo</h1> +<h1 id="18014">Prado Chat Demo</h1> <div id="messages" class="messages"> <com:TPlaceHolder ID="messageList" /> </div> @@ -422,9 +424,9 @@ and a button to send the message. <com:TPlaceHolder ID="userList" /> </div> <div class="message-input"> - <com:TActiveTextBox ID="userinput" + <com:TActiveTextBox ID="userinput" Columns="40" Rows="2" TextMode="MultiLine" /> - <com:TActiveButton ID="sendButton" CssClass="send-button" + <com:TActiveButton ID="sendButton" CssClass="send-button" Text="Send" /> </div> </com:TForm> @@ -436,23 +438,23 @@ 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 +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>Exploring the Active Controls</h2> -<p>We should have some fun before we proceeding with setting up the chat buffering. We want +<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"> -<com:TActiveButton ID="sendButton" CssClass="send-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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90042"> class Home extends TPage { function processMessage($sender, $param) @@ -465,12 +467,12 @@ If you now type something in the main application textbox and click the send but you should see whatever you have typed echoed in the <tt>TJavascriptLogger</tt> console. </p> -<p>To append or add some content to the message list panel, we need to use -some methods in the +<p id="90099" class="block-content">To append or add some content to the message list panel, we need to use +some methods in the <com:DocLink ClassPath="System.Web.UI.ActiveControls.TCallbackClientScript" Text="TCallbackClientScript" /> class which is available through the <tt>CallbackClient</tt> property of the current <tt>TPage</tt> object. For example, we do can do -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90043"> function processMessage($sender, $param) { $this->CallbackClient->appendContent("messages", $this->userinput->Text); @@ -480,24 +482,24 @@ This is one way to update some part of the existing page during a callback (AJAX and will be the primary way we will use to implement the chat application. </p> -<h1>Active Record for <tt>chat_buffer</tt> table</h1> -<p>To send a message to all the connected users we need to buffer or store +<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"> -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 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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90045"> class ChatBufferRecord extends TActiveRecord { public $id; @@ -528,12 +530,12 @@ class ChatBufferRecord extends TActiveRecord </com:TTextHighlighter> </p> -<h1>Chat Application Logic</h1> -<p>We finally arrive at the guts of the chat application logic. First, we +<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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90046"> public function saveMessage() { foreach(ChatUserRecord::finder()->findAll() as $user) @@ -557,19 +559,20 @@ we update the message sender's last activity timestamp. The above piece of code demonstrates the simplicity and succinctness of using ActiveRecords for simple database designs. </p> -<p>The next piece of the logic is to retrieve the users' messages from the buffer. +<p id="90102" class="block-content">The next piece of the logic is to retrieve the users' messages from the buffer. We simply load all the messages for a particular username and format that message appropriately (remember to escape the output to prevent Cross-Site Scripting attacks). After we load the messages, we delete those loaded messages and any older -messages that may have been left in the buffer. +messages that may have been left in the buffer. </p> -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90047"> public function getUserMessages($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 + $this->deleteAll('for_user = ? OR created_on < ?',
+ $user, time() - 300); //5 min inactivity return $content; } @@ -577,14 +580,15 @@ protected function formatMessage($message) { $user = htmlspecialchars($message->from_user); $content = htmlspecialchars($message->message); - return "<div class=\"message\"><strong>{$user}:</strong> <span>{$content}</span></div>"; + 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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90048"> public function getUserList() { $this->deleteAll('last_activity < ?', time()-300); //5 min inactivity @@ -604,11 +608,11 @@ a TRepeater in the template or a custom component). </div> </p> -<h1>Putting It Together</h1> -<p>Now comes to put the application flow together. In the <tt>Home.php</tt> we update +<h1 id="18017">Putting It Together</h1> +<p id="90103" class="block-content">Now comes to put the application flow together. In the <tt>Home.php</tt> we update the <tt>Send</tt> buttons <tt>OnClick</tt> event handler to use the application logic we just implemented. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90049"> function processMessage($sender, $param) { if(strlen($this->userinput->Text) > 0) @@ -617,7 +621,7 @@ function processMessage($sender, $param) $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); @@ -630,17 +634,17 @@ for the current user and update the client side message list using a callback response (AJAX style). </p> -<p>At this point the application is actually already functional, just not very +<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>The next part is perhaps the more tricker and fiddly than the other tasks. We +<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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90050"> protected function refreshUserList() { $lastUpdate = $this->getViewState('userList',''); @@ -654,13 +658,13 @@ protected function refreshUserList() </com:TTextHighlighter> </p> -<p>Actually, we want to periodically update the messages and user list as new +<p id="90106" class="block-content">Actually, we want to periodically update the messages and user list as new users join in and new message may arrive from other users. So we need to refresh the message list as well.</p> -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90051"> function processMessage($sender, $param) { - ... + ... $this->refreshUserList(); $this->refreshMessageList(); ... @@ -681,14 +685,14 @@ protected function refreshMessageList() } </com:TTextHighlighter> The anchor using <tt>time()</tt> as ID for a focus point is so that when the -message list on the client side gets very long, the focus method will +message list on the client side gets very long, the focus method will scroll the message list to the latest message (well, it works in most browsers). </p> -<p>Next, we need to redirect the user back to the login page if the user has +<p id="90107" class="block-content">Next, we need to redirect the user back to the login page if the user has been inactive for some time, say about 5 mins, we can add this check to any stage of the page life-cycle. Lets add it to the <tt>onLoad()</tt> stage. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90052"> public function onLoad($param) { $username = $this->Application->User->Name; @@ -704,18 +708,18 @@ public function onLoad($param) </com:TTextHighlighter> </p> -<h1>Improving User Experience</h1> -<p>The last few details are to periodically check for new messages and +<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"> -<com:TTimeTriggeredCallback OnCallback="refresh" +<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"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_90054"> function refresh($sender, $param) { $this->refreshUserList(); @@ -724,12 +728,12 @@ function refresh($sender, $param) </com:TTextHighlighter> </p> -<p>The final piece requires us to use some javascript. We want that when the +<p id="90109" class="block-content">The final piece requires us to use some javascript. We want that when the user type some text in the textarea and press the <tt>Enter</tt> key, we want it to send the message without clicking on the <tt>Send</tt> button. We add to the <tt>Home.page</tt> some javascript. -<com:TTextHighlighter Language="javascript" CssClass="source"> +<com:TTextHighlighter Language="javascript" CssClass="source block-content" id="code_90055"> <com:TClientScript> Event.observe($("<%= $this->userinput->ClientID %>"), "keypress", function(ev) { @@ -742,11 +746,11 @@ Event.observe($("<%= $this->userinput->ClientID %>"), "keypress", function }); </com:TClientScript> </com:TTextHighlighter> -Details regarding the javascript can be explored in the +Details regarding the javascript can be explored in the <a href="?page=Advanced.Scripts">Introduction to Javascript</a> section of the quickstart. </p> -<p>This completes the tutorial on making a basic chat web application using +<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> |