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authorDaniel Baumann <daniel@debian.org>2024-10-18 20:33:49 +0200
committerDaniel Baumann <daniel@debian.org>2024-12-12 23:57:56 +0100
commite68b9d00a6e05b3a941f63ffb696f91e554ac5ec (patch)
tree97775d6c13b0f416af55314eb6a89ef792474615 /web_src/js/modules/fomantic/dropdown.js
parentInitial commit. (diff)
downloadforgejo-e68b9d00a6e05b3a941f63ffb696f91e554ac5ec.tar.xz
forgejo-e68b9d00a6e05b3a941f63ffb696f91e554ac5ec.zip
Adding upstream version 9.0.3.
Signed-off-by: Daniel Baumann <daniel@debian.org>
Diffstat (limited to '')
-rw-r--r--web_src/js/modules/fomantic/dropdown.js256
1 files changed, 256 insertions, 0 deletions
diff --git a/web_src/js/modules/fomantic/dropdown.js b/web_src/js/modules/fomantic/dropdown.js
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+import $ from 'jquery';
+import {generateAriaId} from './base.js';
+
+const ariaPatchKey = '_giteaAriaPatchDropdown';
+const fomanticDropdownFn = $.fn.dropdown;
+
+// use our own `$().dropdown` function to patch Fomantic's dropdown module
+export function initAriaDropdownPatch() {
+ if ($.fn.dropdown === ariaDropdownFn) throw new Error('initAriaDropdownPatch could only be called once');
+ $.fn.dropdown = ariaDropdownFn;
+ ariaDropdownFn.settings = fomanticDropdownFn.settings;
+}
+
+// the patched `$.fn.dropdown` function, it passes the arguments to Fomantic's `$.fn.dropdown` function, and:
+// * it does the one-time attaching on the first call
+// * it delegates the `onLabelCreate` to the patched `onLabelCreate` to add necessary aria attributes
+function ariaDropdownFn(...args) {
+ const ret = fomanticDropdownFn.apply(this, args);
+
+ // if the `$().dropdown()` call is without arguments, or it has non-string (object) argument,
+ // it means that this call will reset the dropdown internal settings, then we need to re-delegate the callbacks.
+ const needDelegate = (!args.length || typeof args[0] !== 'string');
+ for (const el of this) {
+ if (!el[ariaPatchKey]) {
+ attachInit(el);
+ }
+ if (needDelegate) {
+ delegateOne($(el));
+ }
+ }
+ return ret;
+}
+
+// make the item has role=option/menuitem, add an id if there wasn't one yet, make items as non-focusable
+// the elements inside the dropdown menu item should not be focusable, the focus should always be on the dropdown primary element.
+function updateMenuItem(dropdown, item) {
+ if (!item.id) item.id = generateAriaId();
+ item.setAttribute('role', dropdown[ariaPatchKey].listItemRole);
+ item.setAttribute('tabindex', '-1');
+ for (const el of item.querySelectorAll('a, input, button')) el.setAttribute('tabindex', '-1');
+}
+/**
+ * make the label item and its "delete icon" have correct aria attributes
+ * @param {HTMLElement} label
+ */
+function updateSelectionLabel(label) {
+ // the "label" is like this: "<a|div class="ui label" data-value="1">the-label-name <i|svg class="delete icon"/></a>"
+ if (!label.id) {
+ label.id = generateAriaId();
+ }
+ label.tabIndex = -1;
+
+ const deleteIcon = label.querySelector('.delete.icon');
+ if (deleteIcon) {
+ deleteIcon.setAttribute('aria-hidden', 'false');
+ deleteIcon.setAttribute('aria-label', window.config.i18n.remove_label_str.replace('%s', label.getAttribute('data-value')));
+ deleteIcon.setAttribute('role', 'button');
+ }
+}
+
+// delegate the dropdown's template functions and callback functions to add aria attributes.
+function delegateOne($dropdown) {
+ const dropdownCall = fomanticDropdownFn.bind($dropdown);
+
+ // If there is a "search input" in the "menu", Fomantic will only "focus the input" but not "toggle the menu" when the "dropdown icon" is clicked.
+ // Actually, Fomantic UI doesn't support such layout/usage. It needs to patch the "focusSearch" / "blurSearch" functions to make sure it toggles the menu.
+ const oldFocusSearch = dropdownCall('internal', 'focusSearch');
+ const oldBlurSearch = dropdownCall('internal', 'blurSearch');
+ // * If the "dropdown icon" is clicked, Fomantic calls "focusSearch", so show the menu
+ dropdownCall('internal', 'focusSearch', function () { dropdownCall('show'); oldFocusSearch.call(this) });
+ // * If the "dropdown icon" is clicked again when the menu is visible, Fomantic calls "blurSearch", so hide the menu
+ dropdownCall('internal', 'blurSearch', function () { oldBlurSearch.call(this); dropdownCall('hide') });
+
+ // the "template" functions are used for dynamic creation (eg: AJAX)
+ const dropdownTemplates = {...dropdownCall('setting', 'templates'), t: performance.now()};
+ const dropdownTemplatesMenuOld = dropdownTemplates.menu;
+ dropdownTemplates.menu = function(response, fields, preserveHTML, className) {
+ // when the dropdown menu items are loaded from AJAX requests, the items are created dynamically
+ const menuItems = dropdownTemplatesMenuOld(response, fields, preserveHTML, className);
+ const div = document.createElement('div');
+ div.innerHTML = menuItems;
+ const $wrapper = $(div);
+ const $items = $wrapper.find('> .item');
+ $items.each((_, item) => updateMenuItem($dropdown[0], item));
+ $dropdown[0][ariaPatchKey].deferredRefreshAriaActiveItem();
+ return $wrapper.html();
+ };
+ dropdownCall('setting', 'templates', dropdownTemplates);
+
+ // the `onLabelCreate` is used to add necessary aria attributes for dynamically created selection labels
+ const dropdownOnLabelCreateOld = dropdownCall('setting', 'onLabelCreate');
+ dropdownCall('setting', 'onLabelCreate', function(value, text) {
+ const $label = dropdownOnLabelCreateOld.call(this, value, text);
+ updateSelectionLabel($label[0]);
+ return $label;
+ });
+}
+
+// for static dropdown elements (generated by server-side template), prepare them with necessary aria attributes
+function attachStaticElements(dropdown, focusable, menu) {
+ // prepare static dropdown menu list popup
+ if (!menu.id) {
+ menu.id = generateAriaId();
+ }
+
+ $(menu).find('> .item').each((_, item) => updateMenuItem(dropdown, item));
+
+ // this role could only be changed after its content is ready, otherwise some browsers+readers (like Chrome+AppleVoice) crash
+ menu.setAttribute('role', dropdown[ariaPatchKey].listPopupRole);
+
+ // prepare selection label items
+ for (const label of dropdown.querySelectorAll('.ui.label')) {
+ updateSelectionLabel(label);
+ }
+
+ // make the primary element (focusable) aria-friendly
+ focusable.setAttribute('role', focusable.getAttribute('role') ?? dropdown[ariaPatchKey].focusableRole);
+ focusable.setAttribute('aria-haspopup', dropdown[ariaPatchKey].listPopupRole);
+ focusable.setAttribute('aria-controls', menu.id);
+ focusable.setAttribute('aria-expanded', 'false');
+
+ // use tooltip's content as aria-label if there is no aria-label
+ const tooltipContent = dropdown.getAttribute('data-tooltip-content');
+ if (tooltipContent && !dropdown.getAttribute('aria-label')) {
+ dropdown.setAttribute('aria-label', tooltipContent);
+ }
+}
+
+function attachInit(dropdown) {
+ dropdown[ariaPatchKey] = {};
+ if (dropdown.classList.contains('custom')) return;
+
+ // Dropdown has 2 different focusing behaviors
+ // * with search input: the input is focused, and it works with aria-activedescendant pointing another sibling element.
+ // * without search input (but the readonly text), the dropdown itself is focused. then the aria-activedescendant points to the element inside dropdown
+ // Some desktop screen readers may change the focus, but dropdown requires that the focus must be on its primary element, then they don't work well.
+
+ // Expected user interactions for dropdown with aria support:
+ // * user can use Tab to focus in the dropdown, then the dropdown menu (list) will be shown
+ // * user presses Tab on the focused dropdown to move focus to next sibling focusable element (but not the menu item)
+ // * user can use arrow key Up/Down to navigate between menu items
+ // * when user presses Enter:
+ // - if the menu item is clickable (eg: <a>), then trigger the click event
+ // - otherwise, the dropdown control (low-level code) handles the Enter event, hides the dropdown menu
+
+ // TODO: multiple selection is only partially supported. Check and test them one by one in the future.
+
+ const textSearch = dropdown.querySelector('input.search');
+ const focusable = textSearch || dropdown; // the primary element for focus, see comment above
+ if (!focusable) return;
+
+ // as a combobox, the input should not have autocomplete by default
+ if (textSearch && !textSearch.getAttribute('autocomplete')) {
+ textSearch.setAttribute('autocomplete', 'off');
+ }
+
+ let menu = $(dropdown).find('> .menu')[0];
+ if (!menu) {
+ // some "multiple selection" dropdowns don't have a static menu element in HTML, we need to pre-create it to make it have correct aria attributes
+ menu = document.createElement('div');
+ menu.classList.add('menu');
+ dropdown.append(menu);
+ }
+
+ // There are 2 possible solutions about the role: combobox or menu.
+ // The idea is that if there is an input, then it's a combobox, otherwise it's a menu.
+ // Since #19861 we have prepared the "combobox" solution, but didn't get enough time to put it into practice and test before.
+ const isComboBox = dropdown.querySelectorAll('input').length > 0;
+
+ dropdown[ariaPatchKey].focusableRole = isComboBox ? 'combobox' : 'menu';
+ dropdown[ariaPatchKey].listPopupRole = isComboBox ? 'listbox' : '';
+ dropdown[ariaPatchKey].listItemRole = isComboBox ? 'option' : 'menuitem';
+
+ attachDomEvents(dropdown, focusable, menu);
+ attachStaticElements(dropdown, focusable, menu);
+}
+
+function attachDomEvents(dropdown, focusable, menu) {
+ // when showing, it has class: ".animating.in"
+ // when hiding, it has class: ".visible.animating.out"
+ const isMenuVisible = () => (menu.classList.contains('visible') && !menu.classList.contains('out')) || menu.classList.contains('in');
+
+ // update aria attributes according to current active/selected item
+ const refreshAriaActiveItem = () => {
+ const menuVisible = isMenuVisible();
+ focusable.setAttribute('aria-expanded', menuVisible ? 'true' : 'false');
+
+ // if there is an active item, use it (the user is navigating between items)
+ // otherwise use the "selected" for combobox (for the last selected item)
+ const active = $(menu).find('> .item.active, > .item.selected')[0];
+ if (!active) return;
+ // if the popup is visible and has an active/selected item, use its id as aria-activedescendant
+ if (menuVisible) {
+ focusable.setAttribute('aria-activedescendant', active.id);
+ } else if (dropdown[ariaPatchKey].listPopupRole === 'menu') {
+ // for menu, when the popup is hidden, no need to keep the aria-activedescendant, and clear the active/selected item
+ focusable.removeAttribute('aria-activedescendant');
+ active.classList.remove('active', 'selected');
+ }
+ };
+
+ dropdown.addEventListener('keydown', (e) => {
+ // here it must use keydown event before dropdown's keyup handler, otherwise there is no Enter event in our keyup handler
+ if (e.key === 'Enter') {
+ const dropdownCall = fomanticDropdownFn.bind($(dropdown));
+ let $item = dropdownCall('get item', dropdownCall('get value'));
+ if (!$item) $item = $(menu).find('> .item.selected'); // when dropdown filters items by input, there is no "value", so query the "selected" item
+ // if the selected item is clickable, then trigger the click event.
+ // we can not click any item without check, because Fomantic code might also handle the Enter event. that would result in double click.
+ if ($item?.[0]?.matches('a, .js-aria-clickable')) $item[0].click();
+ }
+ });
+
+ // use setTimeout to run the refreshAria in next tick (to make sure the Fomantic UI code has finished its work)
+ // do not return any value, jQuery has return-value related behaviors.
+ // when the popup is hiding, it's better to have a small "delay", because there is a Fomantic UI animation
+ // without the delay for hiding, the UI will be somewhat laggy and sometimes may get stuck in the animation.
+ const deferredRefreshAriaActiveItem = (delay = 0) => { setTimeout(refreshAriaActiveItem, delay) };
+ dropdown[ariaPatchKey].deferredRefreshAriaActiveItem = deferredRefreshAriaActiveItem;
+ dropdown.addEventListener('keyup', (e) => { if (e.key.startsWith('Arrow')) deferredRefreshAriaActiveItem(); });
+
+ // if the dropdown has been opened by focus, do not trigger the next click event again.
+ // otherwise the dropdown will be closed immediately, especially on Android with TalkBack
+ // * desktop event sequence: mousedown -> focus -> mouseup -> click
+ // * mobile event sequence: focus -> mousedown -> mouseup -> click
+ // Fomantic may stop propagation of blur event, use capture to make sure we can still get the event
+ let ignoreClickPreEvents = 0, ignoreClickPreVisible = 0;
+ dropdown.addEventListener('mousedown', () => {
+ ignoreClickPreVisible += isMenuVisible() ? 1 : 0;
+ ignoreClickPreEvents++;
+ }, true);
+ dropdown.addEventListener('focus', () => {
+ ignoreClickPreVisible += isMenuVisible() ? 1 : 0;
+ ignoreClickPreEvents++;
+ deferredRefreshAriaActiveItem();
+ }, true);
+ dropdown.addEventListener('blur', () => {
+ ignoreClickPreVisible = ignoreClickPreEvents = 0;
+ deferredRefreshAriaActiveItem(100);
+ }, true);
+ dropdown.addEventListener('mouseup', () => {
+ setTimeout(() => {
+ ignoreClickPreVisible = ignoreClickPreEvents = 0;
+ deferredRefreshAriaActiveItem(100);
+ }, 0);
+ }, true);
+ dropdown.addEventListener('click', (e) => {
+ if (isMenuVisible() &&
+ ignoreClickPreVisible !== 2 && // dropdown is switch from invisible to visible
+ ignoreClickPreEvents === 2 // the click event is related to mousedown+focus
+ ) {
+ e.stopPropagation(); // if the dropdown menu has been opened by focus, do not trigger the next click event again
+ }
+ ignoreClickPreEvents = ignoreClickPreVisible = 0;
+ }, true);
+}