/**
* KeyboardNavigation.js
*
* Released under LGPL License.
* Copyright (c) 1999-2017 Ephox Corp. All rights reserved
*
* License: http://www.tinymce.com/license
* Contributing: http://www.tinymce.com/contributing
*/
/**
* This class handles keyboard navigation of controls and elements.
*
* @class tinymce.ui.KeyboardNavigation
*/
define(
'tinymce.ui.KeyboardNavigation',
[
'global!document'
],
function (document) {
"use strict";
var hasTabstopData = function (elm) {
return elm.getAttribute('data-mce-tabstop') ? true : false;
};
/**
* This class handles all keyboard navigation for WAI-ARIA support. Each root container
* gets an instance of this class.
*
* @constructor
*/
return function (settings) {
var root = settings.root, focusedElement, focusedControl;
function isElement(node) {
return node && node.nodeType === 1;
}
try {
focusedElement = document.activeElement;
} catch (ex) {
// IE sometimes fails to return a proper element
focusedElement = document.body;
}
focusedControl = root.getParentCtrl(focusedElement);
/**
* Returns the currently focused elements wai aria role of the currently
* focused element or specified element.
*
* @private
* @param {Element} elm Optional element to get role from.
* @return {String} Role of specified element.
*/
function getRole(elm) {
elm = elm || focusedElement;
if (isElement(elm)) {
return elm.getAttribute('role');
}
return null;
}
/**
* Returns the wai role of the parent element of the currently
* focused element or specified element.
*
* @private
* @param {Element} elm Optional element to get parent role from.
* @return {String} Role of the first parent that has a role.
*/
function getParentRole(elm) {
var role, parent = elm || focusedElement;
while ((parent = parent.parentNode)) {
if ((role = getRole(parent))) {
return role;
}
}
}
/**
* Returns a wai aria property by name for example aria-selected.
*
* @private
* @param {String} name Name of the aria property to get for example "disabled".
* @return {String} Aria property value.
*/
function getAriaProp(name) {
var elm = focusedElement;
if (isElement(elm)) {
return elm.getAttribute('aria-' + name);
}
}
/**
* Is the element a text input element or not.
*
* @private
* @param {Element} elm Element to check if it's an text input element or not.
* @return {Boolean} True/false if the element is a text element or not.
*/
function isTextInputElement(elm) {
var tagName = elm.tagName.toUpperCase();
// Notice: since type can be "email" etc we don't check the type
// So all input elements gets treated as text input elements
return tagName == "INPUT" || tagName == "TEXTAREA" || tagName == "SELECT";
}
/**
* Returns true/false if the specified element can be focused or not.
*
* @private
* @param {Element} elm DOM element to check if it can be focused or not.
* @return {Boolean} True/false if the element can have focus.
*/
function canFocus(elm) {
if (isTextInputElement(elm) && !elm.hidden) {
return true;
}
if (hasTabstopData(elm)) {
return true;
}
if (/^(button|menuitem|checkbox|tab|menuitemcheckbox|option|gridcell|slider)$/.test(getRole(elm))) {
return true;
}
return false;
}
/**
* Returns an array of focusable visible elements within the specified container element.
*
* @private
* @param {Element} elm DOM element to find focusable elements within.
* @return {Array} Array of focusable elements.
*/
function getFocusElements(elm) {
var elements = [];
function collect(elm) {
if (elm.nodeType != 1 || elm.style.display == 'none' || elm.disabled) {
return;
}
if (canFocus(elm)) {
elements.push(elm);
}
for (var i = 0; i < elm.childNodes.length; i++) {
collect(elm.childNodes[i]);
}
}
collect(elm || root.getEl());
return elements;
}
/**
* Returns the navigation root control for the specified control. The navigation root
* is the control that the keyboard navigation gets scoped to for example a menubar or toolbar group.
* It will look for parents of the specified target control or the currently focused control if this option is omitted.
*
* @private
* @param {tinymce.ui.Control} targetControl Optional target control to find root of.
* @return {tinymce.ui.Control} Navigation root control.
*/
function getNavigationRoot(targetControl) {
var navigationRoot, controls;
targetControl = targetControl || focusedControl;
controls = targetControl.parents().toArray();
controls.unshift(targetControl);
for (var i = 0; i < controls.length; i++) {
navigationRoot = controls[i];
if (navigationRoot.settings.ariaRoot) {
break;
}
}
return navigationRoot;
}
/**
* Focuses the first item in the specified targetControl element or the last aria index if the
* navigation root has the ariaRemember option enabled.
*
* @private
* @param {tinymce.ui.Control} targetControl Target control to focus the first item in.
*/
function focusFirst(targetControl) {
var navigationRoot = getNavigationRoot(targetControl);
var focusElements = getFocusElements(navigationRoot.getEl());
if (navigationRoot.settings.ariaRemember && "lastAriaIndex" in navigationRoot) {
moveFocusToIndex(navigationRoot.lastAriaIndex, focusElements);
} else {
moveFocusToIndex(0, focusElements);
}
}
/**
* Moves the focus to the specified index within the elements list.
* This will scope the index to the size of the element list if it changed.
*
* @private
* @param {Number} idx Specified index to move to.
* @param {Array} elements Array with dom elements to move focus within.
* @return {Number} Input index or a changed index if it was out of range.
*/
function moveFocusToIndex(idx, elements) {
if (idx < 0) {
idx = elements.length - 1;
} else if (idx >= elements.length) {
idx = 0;
}
if (elements[idx]) {
elements[idx].focus();
}
return idx;
}
/**
* Moves the focus forwards or backwards.
*
* @private
* @param {Number} dir Direction to move in positive means forward, negative means backwards.
* @param {Array} elements Optional array of elements to move within defaults to the current navigation roots elements.
*/
function moveFocus(dir, elements) {
var idx = -1, navigationRoot = getNavigationRoot();
elements = elements || getFocusElements(navigationRoot.getEl());
for (var i = 0; i < elements.length; i++) {
if (elements[i] === focusedElement) {
idx = i;
}
}
idx += dir;
navigationRoot.lastAriaIndex = moveFocusToIndex(idx, elements);
}
/**
* Moves the focus to the left this is called by the left key.
*
* @private
*/
function left() {
var parentRole = getParentRole();
if (parentRole == "tablist") {
moveFocus(-1, getFocusElements(focusedElement.parentNode));
} else if (focusedControl.parent().submenu) {
cancel();
} else {
moveFocus(-1);
}
}
/**
* Moves the focus to the right this is called by the right key.
*
* @private
*/
function right() {
var role = getRole(), parentRole = getParentRole();
if (parentRole == "tablist") {
moveFocus(1, getFocusElements(focusedElement.parentNode));
} else if (role == "menuitem" && parentRole == "menu" && getAriaProp('haspopup')) {
enter();
} else {
moveFocus(1);
}
}
/**
* Moves the focus to the up this is called by the up key.
*
* @private
*/
function up() {
moveFocus(-1);
}
/**
* Moves the focus to the up this is called by the down key.
*
* @private
*/
function down() {
var role = getRole(), parentRole = getParentRole();
if (role == "menuitem" && parentRole == "menubar") {
enter();
} else if (role == "button" && getAriaProp('haspopup')) {
enter({ key: 'down' });
} else {
moveFocus(1);
}
}
/**
* Moves the focus to the next item or previous item depending on shift key.
*
* @private
* @param {DOMEvent} e DOM event object.
*/
function tab(e) {
var parentRole = getParentRole();
if (parentRole == "tablist") {
var elm = getFocusElements(focusedControl.getEl('body'))[0];
if (elm) {
elm.focus();
}
} else {
moveFocus(e.shiftKey ? -1 : 1);
}
}
/**
* Calls the cancel event on the currently focused control. This is normally done using the Esc key.
*
* @private
*/
function cancel() {
focusedControl.fire('cancel');
}
/**
* Calls the click event on the currently focused control. This is normally done using the Enter/Space keys.
*
* @private
* @param {Object} aria Optional aria data to pass along with the enter event.
*/
function enter(aria) {
aria = aria || {};
focusedControl.fire('click', { target: focusedElement, aria: aria });
}
root.on('keydown', function (e) {
function handleNonTabOrEscEvent(e, handler) {
// Ignore non tab keys for text elements
if (isTextInputElement(focusedElement) || hasTabstopData(focusedElement)) {
return;
}
if (getRole(focusedElement) === 'slider') {
return;
}
if (handler(e) !== false) {
e.preventDefault();
}
}
if (e.isDefaultPrevented()) {
return;
}
switch (e.keyCode) {
case 37: // DOM_VK_LEFT
handleNonTabOrEscEvent(e, left);
break;
case 39: // DOM_VK_RIGHT
handleNonTabOrEscEvent(e, right);
break;
case 38: // DOM_VK_UP
handleNonTabOrEscEvent(e, up);
break;
case 40: // DOM_VK_DOWN
handleNonTabOrEscEvent(e, down);
break;
case 27: // DOM_VK_ESCAPE
cancel();
break;
case 14: // DOM_VK_ENTER
case 13: // DOM_VK_RETURN
case 32: // DOM_VK_SPACE
handleNonTabOrEscEvent(e, enter);
break;
case 9: // DOM_VK_TAB
if (tab(e) !== false) {
e.preventDefault();
}
break;
}
});
root.on('focusin', function (e) {
focusedElement = e.target;
focusedControl = e.control;
});
return {
focusFirst: focusFirst
};
};
}
);
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