welcome to web 2.0 an open laszlo presentation part 2 carlos fernando scheidecker antunes...
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Welcome to WEB 2.0Welcome to WEB 2.0An Open Laszlo presentationAn Open Laszlo presentation
Part 2Part 2
Carlos Fernando Scheidecker AntunesCarlos Fernando Scheidecker [email protected]@cs.utah.edu
http://www.cs.utah.edu/~antunes/AJAXhttp://www.cs.utah.edu/~antunes/AJAX
Feb 15 2006
What is WEB 2.0?What is WEB 2.0?
• Web 2.0 is a term often applied to a perceived ongoing transition of the World Wide Web from a collection of websites to a full-fledged computing platform serving web applications to end users. Ultimately Web 2.0 services are expected to replace desktop computing applications for many purposes.
What is Laszlo ?What is Laszlo ?
• Laszlo is a rich client platform for web application.
• Without realizing, it was the first AJAX application I ever written back in 2004
• It uses Flash, Java, XML and a Servlet engine to provide a rich client desktop like experience for the user.
• It is the future of web and client server applications
Laszlo’s ComponentsLaszlo’s Components
• Compiler
Takes the XML text file (.lzx) and produces the executable in Flash.
• CGI
Use a Servlet, PHP, ASP.net to optionally provide http based SOAP and XML-RPC web services.
Laszlo’s ComponentsLaszlo’s Components
• Run time Framework
Set of Servlets that provide user interface components, data binding, timer, Asynchronous network services
Coding with LaszloCoding with Laszlo
• It is important to understand that Laszlo provides the user side. You can embed JavaScript within your Laszlo XML source code to program the client side.
• Laszlo is the View share of the MVC pattern.
• The business side resides on the CGI applications that provide data for the Desktop much like an AJAX pattern.
Example of Laszlo codeExample of Laszlo code• This is a simple valid LZX source file. Note the XML format:
<canvas>
• <dataset name="dset" • autorequest="true" type="http" • src="getemployees.jsp"/>
• <simplelayout axis="y"/>
• <view datapath="dset:/phonebook/employee">• <simplelayout axis="x"/>• <text datapath="firstName/text()"/>• <text datapath="lastName/text()"/>• <text datapath="phone/text()"/>• </view>
• </canvas>
Development cycleDevelopment cycle
• Develop a Laszlo application requires the following steps:
1 - Define the data sources writing the appropriate CGI programs. These programs will work like a dynamic web application with the difference that data not content is provided and the format is XML
Development cycleDevelopment cycle
• Develop a Laszlo application requires the following steps:
2 – Write the Laszlo source code and compile it through the Laszlo compiler which is a Servlet living inside a container like Tomcat
Development cycleDevelopment cycle
• Develop a Laszlo application requires the following steps:
3 – Test your application
4 – Deploy the application
What’s the catch?What’s the catch?
• Laszlo is a great platform but it requires:
1 – Patience, it takes a while to compile the lzx.
2 – It is hard to code, you need to write a few applications to get proficiency with the platform. Learning curve.
3 – Understand AJAX and GUI application development.
4 – For large deployments clustering load balancing is a must.
Thank you!Thank you!
Please remember:
I will keep the material, examples and source code on the following address:
http://www.cs.utah.edu/~antunes/AJAX/