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@microsoft/windows-admin-center-sdk

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Microsoft - Windows Admin Center Shell

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import { LogLevel } from '../diagnostics/log-level'; import { Logging } from '../diagnostics/logging'; import { Dom } from '../dom/dom'; /** * Class for accessibility manager */ export class AccessibilityManager { /** * Indicates that body focus class handlers have already been setup and should not be setup again */ hiddenFocusHandlersInitialized = false; /** * The set of events for element focusing. */ elementFocusingEvents = []; /** * The CSS class to disable the focus rectangle even in keyboard mode */ hiddenFocusClass = 'sme-hidden-focus'; /** * The CSS class to enable mouse specific accessibility styles */ mouseNavigationModeClass = 'sme-accessibility-mode-mouse'; /** * The CSS class to enable keyboard specific accessibility styles */ keyboardNavigationModeClass = 'sme-accessibility-mode-keyboard'; /** * The set of elements that have had the hiddenFocusClass applied */ hiddenFocusElements = []; /** * The object of ctrl+alt+a key. */ ctrlAltAShortKey; constructor() { // hookup global handlers this.hookupGlobalHandlers(); this.ctrlAltAShortKey = new KeyResolver('Ctrl+Alt+A'); } /** * Registers the event handler for ElementFocusingEvent */ registerElementFocusingEvent(handler) { const unregisterEventFunction = () => { const index = this.elementFocusingEvents.indexOf(handler); if (index !== -1) { this.elementFocusingEvents.splice(index, 1); } }; this.elementFocusingEvents.push(handler); return unregisterEventFunction; } /** * focus on given element and prevent the default of the event * @param element the element to focus on * @param event the event that triggered the focus * @param allowBrowserFocusHandling it indicates whether to allow browser to handle focus. */ focusOnElement(element, event, allowBrowserFocusHandling) { if (element) { // this change needs to be taken in any snap-in implementations // use param {preventScroll: true} if element is in an extension iframe // TODO: try below code with snap-ins that use new snap-in listener code element.focus(); if (!allowBrowserFocusHandling) { event.preventDefault(); } } } /** * Find the first focusable descendant of an element and focus on it * @param element the element to work with * @param event the event that triggered the focus */ focusOnFirstFocusableDescendant(element, event) { const firstFocusableDescendant = Dom.getFirstFocusableDescendent(element); this.focusOnElement(firstFocusableDescendant, event); } /** * Handlers the element focusing in either the default way or custom ways based on ElementFocusingEvent handler. */ processElementFocusing(event, elementToFocus, sourceZone, targetZone, allowBrowserFocusHandling) { let useCustomFocusHandling = false; let preventDefaultEvent = false; this.elementFocusingEvents.forEach(focusEvent => { focusEvent({ nativeEvent: event, sourceZone: sourceZone, targetZone: targetZone, targetElement: elementToFocus, preventDefaultFocusBehavior: () => { useCustomFocusHandling = true; }, preventDefaultEvent: () => { preventDefaultEvent = true; } }); }); if (useCustomFocusHandling) { if (preventDefaultEvent) { event.stopPropagation(); event.preventDefault(); } } else { this.focusOnElement(elementToFocus, event, allowBrowserFocusHandling); } } /** * click on given element and prevent the default of the event * @param element the element to click * @param event the event that triggered the click */ clickOnElement(element, event) { if (element) { element.click(); event.preventDefault(); } } /** * Changes the Accessibility Mode to mouse or keyboard * @param keyboardMode indicates that keyboard mode should be set */ changeAccessibilityMode(keyboardMode) { // toggle accessibility mode across all iframes in the document // only works for same origin iframes // TODO: support cross origin iframes and replace this with RPC broadcasting to all iframes const allBodys = Dom.getAllBodys(); for (let i = 0; i < allBodys.length; i++) { const currentBody = allBodys[i]; currentBody.classList.toggle(this.mouseNavigationModeClass, !keyboardMode); currentBody.classList.toggle(this.keyboardNavigationModeClass, keyboardMode); } // register accessibility mode with self so RPC can use it const self = MsftSme.self(); self.Resources.accessibilityMode = keyboardMode; } /** * Query the accessibility mode of parent */ queryAccessibilityMode() { return !MsftSme.isNullOrUndefined(Dom.getSpecificAncestor(document.body, (x) => Dom.isBody(x) && x.classList.contains(this.keyboardNavigationModeClass))); } /** * Hooks up the global event handlers */ hookupGlobalHandlers() { // hookup body focus class handlers. // We do not need to unhook these as they last the entire applications lifecycle. if (!this.hiddenFocusHandlersInitialized) { // ensure this is only called once this.hiddenFocusHandlersInitialized = true; // apply the mouse navigation class to the body of the document as default this.changeAccessibilityMode(false); // when the user clicks on the page, we need to exit keyboard mode and enter mouse mode again document.body.addEventListener('mousedown', (event) => { // If event.buttons is 0, it means this mouse action is triggered by narrator. // If event.buttons is greater than 0, it means this mouse action is triggered by actual mouse device. // Then exit accessibility mode. if (event.buttons) { this.changeAccessibilityMode(false); setTimeout(() => Dom.checkActiveTab(), 0); } }); document.body.addEventListener('keydown', (event) => { const isKeyboardMode = this.queryAccessibilityMode(); this.changeAccessibilityMode(isKeyboardMode); const currentElement = event.target; const currentElementProperties = Dom.getElementProperties(currentElement); const currentTrap = currentElementProperties.currentTrap; const allowCustomArrowKeyFunctionality = Dom.allowCustomArrowKeyFunctionality(currentElementProperties); const allowCustomHomeEndKeyFunctionality = Dom.allowCustomHomeEndKeyFunctionality(currentElement, currentElementProperties); const currentZone = currentElementProperties.currentZone; const keyCode = event.keyCode; setTimeout(() => Dom.checkActiveTab(), 0); if (event.shiftKey && keyCode === KeyCode.Tab) { // shift tab - go back to previous zone let focusOn = Dom.getPreviousZoneElement(currentElement); const targetZone = Dom.getAncestorZone(focusOn); if (Dom.isTablist(targetZone)) { focusOn = Dom.getFirstActiveOrSelectedDescendant(targetZone) || focusOn; } if (!currentElementProperties.withinTrap || Dom.getAncestorTrap(targetZone) === currentElementProperties.currentTrap) { this.processElementFocusing(event, focusOn, currentZone, targetZone); } else { event.preventDefault(); } // else we are at the beginning of the page and want shift tab to perform its default action } else if (keyCode === KeyCode.Tab) { // when the user presses 'tab' we will enter keyboard mode this.changeAccessibilityMode(true); const focusOn = Dom.getNextZoneElement(currentElement); const targetZone = Dom.getAncestorZone(focusOn); if (focusOn && targetZone !== currentZone) { // go to next zone let newFocusOn = focusOn; if (Dom.isTablist(targetZone)) { newFocusOn = Dom.getFirstActiveOrSelectedDescendant(targetZone); } if (!currentElementProperties.withinTrap || Dom.getAncestorTrap(targetZone) === currentElementProperties.currentTrap) { this.processElementFocusing(event, newFocusOn, currentZone, targetZone); } else { // we are at the end of the trap so go back to the beginning of the trap this.focusOnFirstFocusableDescendant(currentTrap, event); event.preventDefault(); } } else if (!currentElementProperties.withinTrap) { // else we are at the end of the page and want tab to perform its default action const lastElement = Dom.getLastElementInZone(currentElement); if (lastElement) { this.processElementFocusing(event, lastElement, currentZone, targetZone, true); } } else { // we are at the end of the trap so go back to the beginning of the trap this.focusOnFirstFocusableDescendant(currentTrap, event); } } else if (keyCode === KeyCode.RightArrow && allowCustomArrowKeyFunctionality) { // use default if the cursor is in the middle of search box text const useArrowKeys = Dom.useArrowKeysWithinSearchbox(currentElement, true); if (!useArrowKeys && isKeyboardMode) { // go to next focusable element within current zone this.focusOnElement(Dom.getNextFocusableElement(currentElement), event); } } else if (keyCode === KeyCode.DownArrow && allowCustomArrowKeyFunctionality) { // go to next focusable element within current zone this.focusOnElement(Dom.getNextFocusableElement(currentElement), event); } else if (keyCode === KeyCode.UpArrow && allowCustomArrowKeyFunctionality) { // go to previous focusable element within current zone this.focusOnElement(Dom.getPreviousFocusableElement(currentElement), event); } else if (event.keyCode === KeyCode.LeftArrow && allowCustomArrowKeyFunctionality) { // use default if the cursor is in the middle of search box text const useArrowKeys = Dom.useArrowKeysWithinSearchbox(currentElement, false); if (!useArrowKeys && isKeyboardMode) { // go to previous focusable element within current zone this.focusOnElement(Dom.getPreviousFocusableElement(currentElement), event); } } else if (event.keyCode === KeyCode.Enter) { if (document.body.classList.contains(this.keyboardNavigationModeClass)) { if ((currentZone || currentElementProperties.isZone) && (!currentElementProperties.withinForm || Dom.shouldTreatEnterAsClick(currentElement))) { this.clickOnElement(currentElement, event); } } } else if (event.keyCode === KeyCode.End && allowCustomHomeEndKeyFunctionality) { this.focusOnElement(Dom.getLastElementInZone(currentElement), event); } else if (event.keyCode === KeyCode.Home && allowCustomHomeEndKeyFunctionality) { this.focusOnElement(Dom.getFirstElementInZone(currentElement), event); } else if (this.ctrlAltAShortKey.matchesWith(event)) { let targetElement; if (Dom.isInActionBar(currentElement)) { targetElement = Dom.getNextActionBar(currentElement); } else { targetElement = Dom.getFirstActionBar(currentElement); } if (!MsftSme.isNullOrUndefined(targetElement)) { this.changeAccessibilityMode(true); this.focusOnElement(targetElement, event, false); } } }); } } } /** * Class to resolve keys. */ export class KeyResolver { /** * Whether has shift key. */ hasShiftKey = false; /** * Whether has alt key. */ hasAltKey = false; /** * Whether has ctrl key. */ hasCtrlKey = false; /** * The main key code for key combination. */ keyCode; /** * Initializes an instance of KeyLocalizer * @param inputkeys Input keys. */ constructor(inputkeys) { if (!MsftSme.isNullOrWhiteSpace(inputkeys)) { this.resolveKeys(inputkeys); } } /** * Resolves localized keys in to this class structure. * @param inputKeys Input keys. */ resolveKeys(inputKeys) { if (inputKeys === '+') { this.keyCode = KeyCode.Add; return; } const keys = inputKeys.split('+'); if (keys.length > 0 && keys.length === 1) { this.setModifierKeyFlags(keys[0]); this.setKeycode(keys[0]); } else { for (let i = 0; i < keys.length - 1; i++) { this.setModifierKeyFlags(keys[i]); } this.setKeycode(keys[keys.length - 1]); } } /** * Sets modifier key flags if found in key combinations. * @param key The key. */ setModifierKeyFlags(key) { // These should always be passed as english keys. if (key === 'Ctrl') { this.hasCtrlKey = true; } else if (key === 'Alt') { this.hasAltKey = true; } else if (key === 'Shift') { this.hasShiftKey = true; } } /** * Set the key code extracted from the input key. * @param key the key string. */ setKeycode(key) { const keyCode = KeyCode[key]; this.keyCode = keyCode; if (this.keyCode === undefined) { Logging.log({ level: LogLevel.Error, message: 'Could not resolve key ' + key, source: KeyResolver.name }); } } /** * Checks if keyboard event matches with resolved keys. * @param event The keyboard event containing pressed key information. */ matchesWith(event) { return this.hasCtrlKey === event.ctrlKey && this.hasAltKey === event.altKey && this.hasShiftKey === event.shiftKey && this.keyCode === event.keyCode; } } // Keyboard codes export var KeyCode; (function (KeyCode) { KeyCode[KeyCode["Backspace"] = 8] = "Backspace"; KeyCode[KeyCode["Tab"] = 9] = "Tab"; KeyCode[KeyCode["Enter"] = 13] = "Enter"; KeyCode[KeyCode["Shift"] = 16] = "Shift"; KeyCode[KeyCode["Ctrl"] = 17] = "Ctrl"; KeyCode[KeyCode["Alt"] = 18] = "Alt"; KeyCode[KeyCode["Pause"] = 19] = "Pause"; KeyCode[KeyCode["CapsLock"] = 20] = "CapsLock"; KeyCode[KeyCode["Escape"] = 27] = "Escape"; KeyCode[KeyCode["Space"] = 32] = "Space"; KeyCode[KeyCode["PageUp"] = 33] = "PageUp"; KeyCode[KeyCode["PageDown"] = 34] = "PageDown"; KeyCode[KeyCode["End"] = 35] = "End"; KeyCode[KeyCode["Home"] = 36] = "Home"; KeyCode[KeyCode["LeftArrow"] = 37] = "LeftArrow"; KeyCode[KeyCode["UpArrow"] = 38] = "UpArrow"; KeyCode[KeyCode["RightArrow"] = 39] = "RightArrow"; KeyCode[KeyCode["DownArrow"] = 40] = "DownArrow"; KeyCode[KeyCode["Insert"] = 45] = "Insert"; KeyCode[KeyCode["Delete"] = 46] = "Delete"; KeyCode[KeyCode["Num0"] = 48] = "Num0"; KeyCode[KeyCode["Num1"] = 49] = "Num1"; KeyCode[KeyCode["Num2"] = 50] = "Num2"; KeyCode[KeyCode["Num3"] = 51] = "Num3"; KeyCode[KeyCode["Num4"] = 52] = "Num4"; KeyCode[KeyCode["Num5"] = 53] = "Num5"; KeyCode[KeyCode["Num6"] = 54] = "Num6"; KeyCode[KeyCode["Num7"] = 55] = "Num7"; KeyCode[KeyCode["Num8"] = 56] = "Num8"; KeyCode[KeyCode["Num9"] = 57] = "Num9"; KeyCode[KeyCode["A"] = 65] = "A"; KeyCode[KeyCode["B"] = 66] = "B"; KeyCode[KeyCode["C"] = 67] = "C"; KeyCode[KeyCode["D"] = 68] = "D"; KeyCode[KeyCode["E"] = 69] = "E"; KeyCode[KeyCode["F"] = 70] = "F"; KeyCode[KeyCode["G"] = 71] = "G"; KeyCode[KeyCode["H"] = 72] = "H"; KeyCode[KeyCode["I"] = 73] = "I"; KeyCode[KeyCode["J"] = 74] = "J"; KeyCode[KeyCode["K"] = 75] = "K"; KeyCode[KeyCode["L"] = 76] = "L"; KeyCode[KeyCode["M"] = 77] = "M"; KeyCode[KeyCode["N"] = 78] = "N"; KeyCode[KeyCode["O"] = 79] = "O"; KeyCode[KeyCode["P"] = 80] = "P"; KeyCode[KeyCode["Q"] = 81] = "Q"; KeyCode[KeyCode["R"] = 82] = "R"; KeyCode[KeyCode["S"] = 83] = "S"; KeyCode[KeyCode["T"] = 84] = "T"; KeyCode[KeyCode["U"] = 85] = "U"; KeyCode[KeyCode["V"] = 86] = "V"; KeyCode[KeyCode["W"] = 87] = "W"; KeyCode[KeyCode["X"] = 88] = "X"; KeyCode[KeyCode["Y"] = 89] = "Y"; KeyCode[KeyCode["Z"] = 90] = "Z"; KeyCode[KeyCode["LeftWindows"] = 91] = "LeftWindows"; KeyCode[KeyCode["RightWindows"] = 92] = "RightWindows"; KeyCode[KeyCode["Select"] = 93] = "Select"; KeyCode[KeyCode["Numpad0"] = 96] = "Numpad0"; KeyCode[KeyCode["Numpad1"] = 97] = "Numpad1"; KeyCode[KeyCode["Numpad2"] = 98] = "Numpad2"; KeyCode[KeyCode["Numpad3"] = 99] = "Numpad3"; KeyCode[KeyCode["Numpad4"] = 100] = "Numpad4"; KeyCode[KeyCode["Numpad5"] = 101] = "Numpad5"; KeyCode[KeyCode["Numpad6"] = 102] = "Numpad6"; KeyCode[KeyCode["Numpad7"] = 103] = "Numpad7"; KeyCode[KeyCode["Numpad8"] = 104] = "Numpad8"; KeyCode[KeyCode["Numpad9"] = 105] = "Numpad9"; KeyCode[KeyCode["Multiply"] = 106] = "Multiply"; KeyCode[KeyCode["Add"] = 107] = "Add"; KeyCode[KeyCode["Subtract"] = 109] = "Subtract"; KeyCode[KeyCode["DecimaPoint"] = 110] = "DecimaPoint"; KeyCode[KeyCode["Divide"] = 111] = "Divide"; KeyCode[KeyCode["F1"] = 112] = "F1"; KeyCode[KeyCode["F2"] = 113] = "F2"; KeyCode[KeyCode["F3"] = 114] = "F3"; KeyCode[KeyCode["F4"] = 115] = "F4"; KeyCode[KeyCode["F5"] = 116] = "F5"; KeyCode[KeyCode["F6"] = 117] = "F6"; KeyCode[KeyCode["F7"] = 118] = "F7"; KeyCode[KeyCode["F8"] = 119] = "F8"; KeyCode[KeyCode["F9"] = 120] = "F9"; KeyCode[KeyCode["F10"] = 121] = "F10"; KeyCode[KeyCode["F11"] = 122] = "F11"; KeyCode[KeyCode["F12"] = 123] = "F12"; KeyCode[KeyCode["NumLock"] = 144] = "NumLock"; KeyCode[KeyCode["ScrollLock"] = 145] = "ScrollLock"; KeyCode[KeyCode["SemiColon"] = 186] = "SemiColon"; KeyCode[KeyCode["EqualSign"] = 187] = "EqualSign"; KeyCode[KeyCode["Comma"] = 188] = "Comma"; KeyCode[KeyCode["Dash"] = 189] = "Dash"; KeyCode[KeyCode["Period"] = 190] = "Period"; KeyCode[KeyCode["ForwardSlash"] = 191] = "ForwardSlash"; KeyCode[KeyCode["GraveAccent"] = 192] = "GraveAccent"; KeyCode[KeyCode["OpenBracket"] = 219] = "OpenBracket"; KeyCode[KeyCode["BackSlash"] = 220] = "BackSlash"; KeyCode[KeyCode["CloseBraket"] = 221] = "CloseBraket"; KeyCode[KeyCode["SingleQuote"] = 222] = "SingleQuote"; })(KeyCode || (KeyCode = {})); //# sourceMappingURL=accessibility-manager.js.map