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:
// 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:

$callback($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.