Development of a custom field - documentation and/or help needed

-- HikaShop version -- : 4.4.5
-- Joomla version -- : 4.1
-- PHP version -- : 7.4

Is there any documentation available for creation of custom custom fields? I am making progress by looking at the datepickerfield plugin, but various bits are unclear to me, such as

Method plgHikashopDatepickerfield::onFieldsLoad() of the datepickerfield plugin sets a list of options

$me->options = array('required', 'default', 'columnname', 'format', 'allow', 'datepicker_options')

Thanx Nicolas.

A somewhat questionable, but creative way of hiding unused options Unfortunately It has (at least) one undesirable side effect. If no options are in effect for a group, like the Main Attributes for instance, an empty box, with a title but without any option fields, is displayed. Is there an easy way to prevent that?

I have another question, concerning a field's preview in combination with its check() method. My custom field is slightly different the most, in that it returns a stringified JSON value. The value represents a matrix of values, along with some meta data. The number of rows and/or columns for the matrix are field options that need to be set before the field can be used. After they have been set, the preview displays an empty matrix, showing the configured number of rows and/or columns. So far, so good.

The field's check() method makes sure all matrix cells contain a valid, non empty value. It also does so when changing any of the options, i.e. changing the number of rows and/or columns. However, when saving the field, the check() method fails and does not allow the field to be saved. I tried to enter some dummy data in the preview matrix, but for some reason the resulting JSON value does not get passed into the check() method.

I have two questions:

• Why is the field value of the preview field not passed into the check() method?
• Is there a way to detect in the check() method if I'm editing the field's options or the actual item the field is meant to be used for?

Thanks Nicolas. Your answer to my second question allows me to check on the default field. Because the field has no sensible default value, the check can no always return true.

For clarification of my first question, I added a screen shot of the custom field edit interface. As you can see the MAIN ATTRIBUTES area is completely empty. It would be user friendly to not display empty such empty areas.

Thanx again Nicolas!

Yet another question.

I have a more or less working custom field type now. I can add it as a new custom field to table "product" and, when creating a new product, I can fill in the data for that field in the "CUSTOM FIELDS" section. The problem is I don't see that data in the product. Not in the parameter for the "onBeforeCalculateProductPriceForQuantity" event handler and also not when loading products using the product class like so: $productClass->getProducts([$productId]).

What am I missing here?

Hi Nicolas,

Thanks again for the swift response. This time I feel really stupid, because I was testing with a faulty product; a product without my custom field. I feel embarrassed and apologize for wasting your time

Hoping I haven't overlooked the obvious once again, I have a new question.

My custom field is not meant for the front end but specifically for the back end. When editing a product, the custom field shows up in the "CUSTOM FIELDS" area, like it is supposed to. However, if the product has Variants, it also shows up on Variant editing pages. Is there a way to prevent that? Not just hide it, with CSS or something, but not include it on the page at all? If it exists on the page, the validation will be triggered and most certainly fail, preventing the page from being saved.