TDDD24 Web programming and Interactivity

FAQ

General questions

The tag: "table" doesn't have an attribute: "height" in currently active versions.[HTML 4.0] The same error occur if I use HTML 4.01 or XHTML 1.0 Transitional. How Can I fix it ?

Firstly, you cannot use height atrribute for tr and table tags because it has
been deprecated and u can use it only in td and th.

My html pages works fine but it does not get validated ?

Some of the html tags and attributes have been deprecated in the later versions of html. Check this link here for more
detailed information.

I can only see a blank page when coding in PHP, how do I avoid that? Normally when the PHP interpreter at IDA encounters an error in the php script it will not generate any output at all. This will make debugging of your scripts quite a difficult matter. Luckily you can change this behaviour and have PHP output an error notification in these situations instead. This is done by adding the following code to your PHP-script, preferrably at the very beginning of the script:

<?php ini_set('display_errors', 1); ?> 

How can I install Joomla components @ IDA? Due to Safe Mode in PHP, you'll have to use manual registration of components and not the GUI in the administration panel. See the guide "Developing Joomla components" and especially the section about "Registering Your Component in the Database".
I am trying to view my component but I only get 404 - Component not found or My page is displaying nothing. Its totally blank. Whts wrong?

There are quite couple of reasons for this. It may be because of misspelt component name,
invalid entires in database while creating component, improper url etc.. Check all of them once again. Also, add this in all your php files for more appropriate errors if you have any ini_set('display_errors', 'on');

I have tried all of them above but still I get the same error. Why ?

Make sure creator of the files and owner of the account where joomla is installed is same.

How to view my component that I have created?

Example : http://www-und.ida.liu.se/~username/cms/index.php?option=com_manuscripts

Do I need to set any other classpath for my GWT application to get complied and executed ?

Yes , you need to add the xmlrpc jar files in the classpath , there is a module that does this for you. module add /home/TDDD24/xmlrpc.module Then add the $CLASSAPTH variable to your Filename-compile and Filename-shell script java -cp "$CLASSPATH:$APPDIR/src ......"

How do I get data frm db ? Should it be in the form of xml ?

Use the joomla db module or access your database directly through mysql driver.
No need to format it to xml , the xml-rpc plugin will take care of that for you.

How do I integrate my GWT application in joomla ?

Create an iframe somewhere inside joomla(component), with a link to your gwt html.

I am unable to compile my servlet file. Whats wrong ? zaza1 <339> javac ReviewServlet.java ReviewServlet.java:3: package com.google.gwt.user.client.rpc does not exist import com.google.gwt.user.client.rpc.RemoteService; ReviewServlet.java:6: cannot find symbol symbol: class RemoteService public interface ReviewServlet extends RemoteService

You are missing to add src directory your classpath CLASSPATH=$CLASSPATH:/home/username/your path to source folder

I am unable to retrieve values from database( in joomla.php).
However, I am able to view all my methods defined in joomla.php through xmlrpc debugger link. Whats wrong ?

Check whether you are able to call the function from the debugger. (do you get something back in response) .
If no , call your function from a normal php-file to get some error messages.

Do we have to make an RPC-call from our GWT backend to Joomla
in order to get information out of our database? How to do that ?

Yes, Joomla provides xmlrpc plugin for you. you will find this in /cms/plugins/xmlrpc/joomla.php. Add webservices and corresponding function in that file and these functions will actually contacts database.
One function "searchsite" is already given as example. After doing this use xmlrpc debugger to check ur functions r ok or not and then connect
your severlet file to joomla.php through xmlrpc config and calls

What is the servlet xmlrpcurl to connect to joomla plugin ?

Its config.setServerURL(new URL("http://www-und.ida.liu.se/~sardr230/cms/xmlrpc/index.php"));

What is the return type of a varibles by joomla plugin ?

It is important to note that joomla plugin(like xmlrpc/joomla.php or blogger.php) returns object as a returntype.
No matter what varible types you use in these files,the final return value will be object type. If you are using arrays then pass the variable like anyother type, no need of conversion
Eg: return $variable Unable to connect joomla with Google Calender ?

Provided correct calender feed and make the Google calendar public as well

How do I group Google Calendar items according to their date using XSLT? See this thread on IBM DeveloperWorks for hints. How to get started with sandbox paypal system ?

Here is the link to the pdf file Click here

I am working with paypal system on Windows Environment and I see all blank pages while execution. Whats wrong ?

If you working on windows, we recommend you to use XAMPP server for this lab.
You need to enable curl extension in XAMPP.

How to enable curl extension in XAMPP(Windows)?

To enable curl library with XAMPP we need to modify the php.ini files in our xampp folder.
1) Locate the following files:
C:\Program Files\xampp\apache\bin\php.ini
C:\Program Files\xampp\php\php.ini
C:\Program Files\xampp\php\php4\php.ini
2) Uncomment the following line on your php.ini file by removing the semicolon.
;extension=php_curl.dll
3) Restart your apache server.
4) Check your phpinfo if curl was properly enabled.

Page responsible: Henrik Eriksson
Last updated: 2010-01-29