[menu] Define a default checked attribute for menuitem

[lukewarlow]

It's useful to be able to define an initially checked state for menuitems that are checkable. Bikeshedding of naming would be needed.

[css-meeting-bot]

The Open UI Community Group just discussed [menu] Define a default checked attribute for menuitem, and agreed to the following:

• RESOLVED: `defaultchecked` content attribute reflected into `defaultChecked` IDL boolean attribute, to cover initial-ness; then a `checked` IDL boolean attribute to track live-checked-ness (no content attribute though)

The full IRC log of that discussion

<masonf> scribenick: jarhar
<jarhar> domfarolino: my original proposal was to simplify html input element stuff by having a checked attribute that is synced, but then mason explained why its complicated for the open attribute on details and dialog
<jarhar> domfarolino: so we talked about having a defaultchecked html attribute which sets the default, and then having a checked idl attribute
<jarhar> domfarolino: this is probably how we would design input if we did that today
<masonf> q+
<jarhar> domfarolino: if we agree that its the right thing to do, ill include this behavior in my prototype
<masonf> ack mason
<jarhar> masonf: +1 from me. luke put in the issue the bikeshed of naming. defaultchecked sounds like the platform. for me i like initially, which means that attribute only takes care of the initial conditions. default kind of does but its nebulous. if the platform is what we care about then defaultchecked is fine
<frehner> q?
<frehner> q+
<masonf> ack frehner
<jarhar> frehner: this isn't a form element so it wouldnt be like a checkbox where its value is on where its not set?
<jarhar> domfarolino: what do you mean by on and name? we dont have the name attribute to group exclusive radio versions of this
<jarhar> frehner: i was just thinking about checkboxes in forms and their submission values, and its defaulting to "on" if you dont provide a value. but these arent form elements so we dont have to worry about this sort of behavior
<jarhar> masonf: yes, not a form element
<domfarolino> Resolution: `defaultchecked` content attribute reflected into `defaultChecked` IDL boolean attribute, to cover initial-ness; then a `checked` boolean attribute to track live-checked-ness; no content attribute for live checkedness.
<masonf> +1
<jarhar> +1
<frehner> +1
<domfarolino> RESOLVED: `defaultchecked` content attribute reflected into `defaultChecked` IDL boolean attribute, to cover initial-ness; then a `checked` IDL boolean attribute to track live-checked-ness (no content attribute though)