Developing a MVC Component/Adding categories
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Revision as of 08:10, 12 March 2013 by Neo314 (talk | contribs) (→The helper filename is important: new section)
Why $query = new JDatabaseQuery; but not $query = &new JDatabaseQuery; ?
In ../models/fields/helloworld.php on line 29
If you use the line, $query = new JDatabaseQuery;, component works, but when helloworlds is added as menu item it causes the following error when item is clicked:
Fatal error: Cannot instantiate abstract class JDatabaseQuery in C:\xampp\htdocs\test_site\administrator\components\com_helloworld\models\fields\helloworld.php on line 29
Reverting back to code from part 11, $query = $db->getQuery(true);, does not throw error.
Just an observation.
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People who are using Joomla >= 2.5.5. will probably encounter a problem with categories menu - buttons for basic user actions missing (such as "New", "Edit" etc.) The solution can be found here: http://forum.joomla.org/viewtopic.php?f=642&t=730171
Additional explanation about the controller helloworld.php file changes would be helpful.[edit]
The controller helloworld.php file changes from
// set default view if not set
JRequest::setVar('view', JRequest::getCmd('view', 'HelloWorlds'));
To
// set default view if not set
$input = JFactory::getApplication()->input;
$input->set('view', $input->getCmd('view', 'HelloWorlds'));
without any explanation as to the changes.
- JRequest is depricated and JInput is to be used
The helper filename is important[edit]
I think this is the first place the helper file was discussed, and I found out the hard way that the file name needs to be the component name (in lower case I think). HelloWorldHelper.php (named after the class) seemed to work in every respect except for maintaining the submenu when on the categories submenu item. It has to be helloworld.php