Widget refactor backward compat issues

[laundmo]

It seems my widget refactor had issues with backwards compatibility, specifically in a way that should have been compatible, and was recently reverted.

I'd like to ask the affected user to please share the widgets they were trying to use, and the errors they got, so i can fix this and add the new widgets system back.

- laund

[laundmo]

I've resolved one of the issues shared in https://groups.google.com/g/py4web/c/dfAehLbcqtg regarding FormStyle.widgets['fieldname'] = CustomWidget

https://github.com/web2py/py4web/pull/1001

[Massimo DiPierro]

I am going to review your PR asap, would be great if other users who use custom widgets could also test it with their code.

[Massimo DiPierro]

To people who use custom widgets. I would very much appreciate if you could try this changes and see if they break your code or not. 

[CarlosDB]

I’ve been testing this refactor (https://github.com/web2py/py4web/pull/1001) because the feature that allows widgets to have a read-only version (def make_readonly(self, value)) seems extremely useful.

I haven’t evaluated the widget registration mechanism yet.
However, I’ve run into major issues with my custom widgets, and at the moment it doesn’t seem easy to make them work with this change.

1. Constructor parameters for widget classes

Before:

form_style.widgets['select_field'] = WidgetTomSelect(create=False)

Now:

form_style.widgets['select_field'] = WidgetTomSelect

With the new approach, I can no longer pass parameters to the widget constructor.
This makes it impossible to configure widgets that need runtime options.

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2. Using default widgets inside custom widgets

For example, my WidgetTomSelect:

class WidgetTomSelect: def __init__(self, create: bool = False): self.create = create def make(self, field, value, error, title, placeholder="", readonly=False): if not hasattr(field.requires, 'options'): raise ValueError('This field does not support WidgetTomSelect') widget = SelectWidget().make(field, value, error, title, placeholder, readonly) widget['_class'] = (widget.attributes.get('_class', '') + ' tomselect').strip() return widget

With the refactor, it is now impossible to instantiate SelectWidget directly, so this pattern no longer works.

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3. OldWidgetCompat instantiation

In:

class OldWidgetCompat(Widget): """Handles custom widgets from the older style, which have a .make(self, field, value, error, title, placeholder="", readonly=False) and don't inherit from Widget""" def __init__(self, old_widget, field, form_style, vars, error=None): super().__init__(field, form_style, vars, error) self.old_widget = old_widget

It seems that old_widget should actually be instantiated:

self.old_widget = old_widget()

Otherwise, old-style widgets that expect instance state cannot work correctly.

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4. MakeReadonlyMixin inheritance order

Finally, the standard py4web widgets are now defined like this:

class InputTypeWidget(Widget, MakeReadonlyMixin):

But MakeReadonlyMixin does not seem to have any effect in this order.
Should this instead be:

class InputTypeWidget(MakeReadonlyMixin, Widget):

so that the mixin methods properly override or extend the base behavior?

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Overall, I really like the idea behind make_readonly, but at least in my case, migrating existing custom widgets has been quite difficult with the current design.

Thanks for the work on this — I hope this feedback is useful.

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