Twenty Twelve: Add aria-expanded support to menu button (mobile)

[bschneidewind]

This adds the aria-expanded and aria-controls attributes to the mobile nav of the Twenty Twelve theme - they currently are not present, ex: https://wp-themes.com/twentytwelve/

Trac ticket: https://core.trac.wordpress.org/ticket/62892

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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[github-actions]

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[umeshsinghin]

@bschneidewind Please use const and let for block-scoped variables (no var).

[joedolson]

@umeshsinghin While that's generally good advice, it's generally WordPress policy to keep things stylistically consistent within the context they're written. Since most of this file uses var to declare variables, it isn't a requirement.

Note the JavaScript coding standards, which explicitly indicate that const and let should be used in code written using ES2015 or newer; which is definitely not the case with Twenty Twelve.

It's not a problem to use more modern notations in older files, but not necessary, either.

[sabernhardt]

I think this can be done without declaring new variables by editing the main function (and reusing its button and menu variables). I also recommend setting aria-expanded="false" in the script file in case a child theme overrides the header template.

	// Assign an ID for the default page list if no menu is set as Primary.
	if ( ! menu.id ) {
		menu.setAttribute( 'id', 'twentytwelve-page-list-menu' );
	}

	button.setAttribute( 'aria-controls', menu.id );
	button.setAttribute( 'aria-expanded', 'false' );

	button.onclick = function() {
		if ( -1 === menu.className.indexOf( 'nav-menu' ) ) {
			menu.className = 'nav-menu';
		}

		if ( -1 !== button.className.indexOf( 'toggled-on' ) ) {
			button.className = button.className.replace( ' toggled-on', '' );
			menu.className = menu.className.replace( ' toggled-on', '' );
			button.setAttribute( 'aria-expanded', 'false' );
		} else {
			button.className += ' toggled-on';
			menu.className += ' toggled-on';
			button.setAttribute( 'aria-expanded', 'true' );
		}
	};

[bschneidewind]

Thanks @sabernhardt ~ just adjusted the approach!

[sabernhardt]

This worked for me in my local SVN installation

• in Firefox and Chrome on Windows 11
• with a Primary Menu or with the default page list as the main menu
• with additional menus in the header.php of a child theme (the attributes only apply to the first menu)

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 59911
GitHub commit: 5aa3534

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.