Hookable method that is called whenever a property has changed while change tracking is enabled.
- Enables hooks to monitor changes to the object.
- Do not call this method directly, as the
Wire::trackChange()method already does so. - Descending classes should call
$this->trackChange('name', $oldValue, $newValue);when a property they are tracking has changed.
Usage
// basic usage
$wire->changed(string $what);
// usage with all arguments
$wire->changed(string $what, mixed $old = null, mixed $new = null);Arguments
| Name | Type(s) | Description |
|---|---|---|
what | string | Name of property that changed |
old (optional) | mixed | Previous value before change |
new (optional) | mixed | New value |
Hooking Wire::changed(…)
You can add your own hook events that are executed either before or after the Wire method is executed. Examples of both are included below. A good place for hook code such as this is in your /site/ready.php file.
Hooking before
The 'before' hooks are called immediately before each Wire method call is executed. This type of hook is especially useful for modifying arguments before they are sent to the method.
$this->addHookBefore('Wire::changed', function(HookEvent $event) {
// Get the object the event occurred on, if needed
$Wire = $event->object;
// Get values of arguments sent to hook (and optionally modify them)
$what = $event->arguments(0);
$old = $event->arguments(1);
$new = $event->arguments(2);
/* Your code here, perhaps modifying arguments */
// Populate back arguments (if you have modified them)
$event->arguments(0, $what);
$event->arguments(1, $old);
$event->arguments(2, $new);
}); Hooking after
The 'after' hooks are called immediately after each Wire method call is executed. This type of hook is especially useful for modifying the value that was returned by the method call.
$this->addHookAfter('Wire::changed', function(HookEvent $event) {
// Get the object the event occurred on, if needed
$Wire = $event->object;
// An 'after' hook can retrieve and/or modify the return value
$return = $event->return;
// Get values of arguments sent to hook (if needed)
$what = $event->arguments(0);
$old = $event->arguments(1);
$new = $event->arguments(2);
/* Your code here, perhaps modifying the return value */
// Populate back return value, if you have modified it
$event->return = $return;
}); See Also
API reference based on ProcessWire core version 3.0.244