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Posted to commits@tapestry.apache.org by bu...@apache.org on 2015/08/08 22:19:49 UTC
svn commit: r961182 - in /websites/production/tapestry/content:
cache/main.pageCache implementing-the-hi-lo-guessing-game.html
Author: buildbot
Date: Sat Aug 8 20:19:48 2015
New Revision: 961182
Log:
Production update by buildbot for tapestry
Modified:
websites/production/tapestry/content/cache/main.pageCache
websites/production/tapestry/content/implementing-the-hi-lo-guessing-game.html
Modified: websites/production/tapestry/content/cache/main.pageCache
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Binary files - no diff available.
Modified: websites/production/tapestry/content/implementing-the-hi-lo-guessing-game.html
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--- websites/production/tapestry/content/implementing-the-hi-lo-guessing-game.html (original)
+++ websites/production/tapestry/content/implementing-the-hi-lo-guessing-game.html Sat Aug 8 20:19:48 2015
@@ -68,7 +68,7 @@
<div id="content">
<div id="ConfluenceContent"><p><span style="line-height: 1.4285715;"><br clear="none"></span></p><p><span style="line-height: 1.4285715;">Let's start building a basic Hi-Lo Guessing game.</span></p><p>In the game, the computer selects a number between 1 and 10. You try and guess the number, clicking links. At the end, the computer tells you how many guesses you required to identify the target number. Even a simple example like this will demonstrate several important concepts in Tapestry:</p><ul><li>Breaking an application into individual pages</li><li>Transferring information from one page to another</li><li>Responding to user interactions</li><li>Storing client information in the server-side session</li></ul><p>We'll build this little application in small pieces, using the kind of iterative development that Tapestry makes so easy.</p><p><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image" src="implementing-the-hi-lo-guessing-game.data/hilo-flow.png"
></span></p><p>Our page flow is very simple, consisting of three pages: Index (the starting page), Guess and GameOver. The Index page introduces the application and includes a link to start guessing. The Guess page presents the user with ten links, plus feedback such as "too low" or "too high". The GameOver page tells the user how many guesses they took before finding the target number.</p><h1 id="ImplementingtheHi-LoGuessingGame-IndexPage">Index Page</h1><p>Let's get to work on the Index page and template. Make Index.tml look like this:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.tml</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html t:type="layout" title="Hi/Lo Guess"
- xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
+ xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd">
<p>
I'm thinking of a number between one and ten ...
@@ -157,7 +157,7 @@ public class Index
</pre>
</div></div><p>The new event handler method now chooses the target number, and tells the Guess page about it. Because Tapestry is a managed environment, we don't just create an instance of Guess ... it is Tapestry's responsibility to manage the life cycle of the Guess page. Instead, we ask Tapestry for the Guess page, using the @InjectPage annotation.</p><div class="confluence-information-macro confluence-information-macro-note"><span class="aui-icon aui-icon-small aui-iconfont-warning confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>All fields in a Tapestry page or component class must be <strong>non-public</strong>.</p></div></div><p>Once we have that Guess page instance, we can invoke methods on it normally.</p><p>Returning a page instance from an event handler method directs Tapestry to send a client-side redirect to the returned page, rather than sending a redirect for the active page. Thus once the user clicks the "start guessing" lin
k, they'll see the Guess page.</p><div class="confluence-information-macro confluence-information-macro-warning"><span class="aui-icon aui-icon-small aui-iconfont-error confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>When creating your own applications, make sure that the objects stored in final variables are thread safe. It seems counter-intuitive, but final variables are shared across many threads. Ordinary instance variables are not. Fortunately, the implementation of Random is, in fact, thread safe.</p></div></div><p>So ... let's click the link and see what we get:</p><p><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image" src="implementing-the-hi-lo-guessing-game.data/guess-template-missing.png"></span></p><p>Ah! We didn't create a Guess page template. Tapestry was really expecting us to create one, so we better do so.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader pan
elHeader pdl" style="border-bottom-width: 1px;"><b>src/main/resources/com/example/tutorial/pages/Guess.tml</b></div><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;"><html t:type="layout" title="Guess The Number"
- xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
+ xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd">
<p>
The secret number is: ${target}.
@@ -176,7 +176,7 @@ public class Index
</pre>
</div></div><p>This doesn't have anything to do with database persistence (that's coming up in a later chapter). It means that the value is stored in the HttpSession between requests.</p><p>Go back to the Index page and click the link again. Finally, we have a target number:</p><p><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image" src="implementing-the-hi-lo-guessing-game.data/guess-target.png"></span></p><p>That's enough for us to get started. Let's build out the Guess page, and get ready to let the user make guesses. We'll show the count of guesses, and increment that count when they make them. We'll worry about high and low and actually selecting the correct value later.</p><p>When building Tapestry pages, you sometimes start with the Java code and build the template to match, and sometime start with the template and build the Java code to match. Both approaches are valid. Here, lets start with the markup in the template, then figure out what we
need in the Java code to make it work.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Guess.tml (revised)</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html t:type="layout" title="Guess The Number"
- xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd"
+ xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd"
xmlns:p="tapestry:parameter">
<p>
@@ -281,7 +281,7 @@ public class GameOver
</pre>
</div></div><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>GameOver.tml</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html t:type="layout" title="Game Over"
- xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd"
+ xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd"
xmlns:p="tapestry:parameter">
<p>