Preset a field in the backend

[astock]

Hello everyone, is there a way to preset a field in the backend with the value of the last entry?

An example: A start and end mileage is entered in a logbook. For a new trip, the end mileage of the last trip should become the start mileage of the new trip.

I can't find a way to show the value in the template. Is it possible with a hook?

[iank]

Yes, I think a hook would be needed. Something like this should give you a start, added to site/ready.php:

$wire->addHookBefore("ProcessPageEdit::buildForm", function (HookEvent $event) {
	$page = $event->object->getPage();
	$myTemplate = "logbook"; //or whatever your template is called
	if ($page->template != $myTemplate) return;
	if ($page->startMileage) return; //not if the start Mileage is present
	$prevPage = wire('pages')->get("template=$myTemplate,endMileage!=,sort=-created"); //get the most recent logbook with an endMileage value
	if ($prevPage->id) {
		$page->startMileage = $prevPage->endMileage;
	}
});

 

[astock]

Hi iank, sorry for my late reply and thanks for your effort!

I entered the code and it gives me a value - unfortunately from the wrong vehicle. It should depend on the previously selected car wich is the parent template. At the moment it brings me the value of each vehicle.

[iank]

Hi @astock, 

No problem.  You just need to check for the new page's parent in the selector, something like this:

$wire->addHookBefore("ProcessPageEdit::buildForm", function (HookEvent $event) {
	$page = $event->object->getPage();
	$myTemplate = "logbook"; //or whatever your template is called
	if ($page->template != $myTemplate) return;
	if ($page->startMileage) return; //not if the start Mileage is present
	$parent = $page->parent; //get the current page's parent
	//get the most recent logbook with an endMileage value for the current parent
	$prevPage = wire('pages')->get("template=$myTemplate,endMileage!=,parent=$parent,sort=-created"); 
	if ($prevPage->id) {
		$page->startMileage = $prevPage->endMileage;
	}
});

 

[astock]

Hi @iank,
wow, it works great! Thank you for your help and solving the problem.