Callbacks are nifty

[filburt1]

I finally found a way to emulate an event firing model from Java: callbacks. http://www.php.net/callback and http://www.php.net/create_function . Nowhere near as clean as Java with implementing interfaces and providing listeners, but it works:

PHP Code:

// go-go anonymous functions
$callback = create_function(
        "\$step, \$stepcount, \$status, \$result = false",
        "if (\$step >= 0)
        {
            vbms_installer_update_progress(\$step, \$stepcount, \$status);
        }
        else
        {
            vbms_installer_die(\$status, \$result);
        }");
$installer->upgrade($callback); 


Now $installer->upgrade() will fire the callback function as it executes, providing status updates. Calling the callback is as simple as:

PHP Code:

$callback($step, $stepcount, $status); 


Of course, in Java, it would be more like:

installer.addUpdateListener(new InstallerUpdateListener()
{
    public void statusChanged(int step, int stepCount, String status, Object result)
    {
        ...
    }
});
installer.upgrade();

...but that would require PHP 5 at least because of the abstractifiedness needed.

[Andreas]

May I ask why you are using create_function()?

[filburt1]

To create an anonymous function rather than one publicly accessible by every other bit of code.