| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| cr.define('uber', function() { |
| /** |
| * Options for how web history should be handled. |
| */ |
| var HISTORY_STATE_OPTION = { |
| PUSH: 1, // Push a new history state. |
| REPLACE: 2, // Replace the current history state. |
| NONE: 3, // Ignore this history state change. |
| }; |
| |
| /** |
| * We cache a reference to the #navigation frame here so we don't need to grab |
| * it from the DOM on each scroll. |
| * @type {Node} |
| * @private |
| */ |
| var navFrame; |
| |
| /** |
| * Handles page initialization. |
| */ |
| function onLoad(e) { |
| navFrame = $('navigation'); |
| navFrame.dataset.width = navFrame.offsetWidth; |
| |
| // Select a page based on the page-URL. |
| var params = resolvePageInfo(); |
| showPage(params.id, HISTORY_STATE_OPTION.NONE, params.path); |
| |
| window.addEventListener('message', handleWindowMessage); |
| window.setTimeout(function() { |
| document.documentElement.classList.remove('loading'); |
| }, 0); |
| |
| // HACK(dbeam): This makes the assumption that any second part to a path |
| // will result in needing background navigation. We shortcut it to avoid |
| // flicker on load. |
| // HACK(csilv): Search URLs aren't overlays, special case them. |
| if (params.id == 'settings' && params.path && |
| params.path.indexOf('search') != 0) { |
| backgroundNavigation(); |
| } |
| |
| ensureNonSelectedFrameContainersAreHidden(); |
| } |
| |
| /** |
| * Find page information from window.location. If the location doesn't |
| * point to one of our pages, return default parameters. |
| * @return {Object} An object containing the following parameters: |
| * id - The 'id' of the page. |
| * path - A path into the page, including search and hash. Optional. |
| */ |
| function resolvePageInfo() { |
| var params = {}; |
| var path = window.location.pathname; |
| if (path.length > 1) { |
| // Split the path into id and the remaining path. |
| path = path.slice(1); |
| var index = path.indexOf('/'); |
| if (index != -1) { |
| params.id = path.slice(0, index); |
| params.path = path.slice(index + 1); |
| } else { |
| params.id = path; |
| } |
| |
| var container = $(params.id); |
| if (container) { |
| // The id is valid. Add the hash and search parts of the URL to path. |
| params.path = (params.path || '') + window.location.search + |
| window.location.hash; |
| } else { |
| // The target sub-page does not exist, discard the params we generated. |
| params.id = undefined; |
| params.path = undefined; |
| } |
| } |
| // If we don't have a valid page, get a default. |
| if (!params.id) |
| params.id = getDefaultIframe().id; |
| |
| return params; |
| } |
| |
| /** |
| * Handler for window.onpopstate. |
| * @param {Event} e The history event. |
| */ |
| function onPopHistoryState(e) { |
| if (e.state && e.state.pageId) |
| showPage(e.state.pageId, HISTORY_STATE_OPTION.NONE); |
| } |
| |
| /** |
| * @return {Object} The default iframe container. |
| */ |
| function getDefaultIframe() { |
| return $(loadTimeData.getString('helpHost')); |
| } |
| |
| /** |
| * @return {Object} The currently selected iframe container. |
| */ |
| function getSelectedIframe() { |
| return document.querySelector('.iframe-container.selected'); |
| } |
| |
| /** |
| * Handles postMessage calls from the iframes of the contained pages. |
| * |
| * The pages request functionality from this object by passing an object of |
| * the following form: |
| * |
| * { method : "methodToInvoke", |
| * params : {...} |
| * } |
| * |
| * |method| is required, while |params| is optional. Extra parameters required |
| * by a method must be specified by that method's documentation. |
| * |
| * @param {Event} e The posted object. |
| */ |
| function handleWindowMessage(e) { |
| if (e.data.method === 'beginInterceptingEvents') |
| backgroundNavigation(); |
| else if (e.data.method === 'stopInterceptingEvents') |
| foregroundNavigation(); |
| else if (e.data.method === 'setPath') |
| setPath(e.origin, e.data.params.path); |
| else if (e.data.method === 'setTitle') |
| setTitle(e.origin, e.data.params.title); |
| else if (e.data.method === 'showPage') |
| showPage(e.data.params.pageId, HISTORY_STATE_OPTION.PUSH); |
| else if (e.data.method === 'navigationControlsLoaded') |
| onNavigationControlsLoaded(); |
| else if (e.data.method === 'adjustToScroll') |
| adjustToScroll(e.data.params); |
| else if (e.data.method === 'mouseWheel') |
| forwardMouseWheel(e.data.params); |
| else |
| console.error('Received unexpected message', e.data); |
| } |
| |
| /** |
| * Sends the navigation iframe to the background. |
| */ |
| function backgroundNavigation() { |
| navFrame.classList.add('background'); |
| navFrame.firstChild.tabIndex = -1; |
| navFrame.firstChild.setAttribute('aria-hidden', true); |
| } |
| |
| /** |
| * Retrieves the navigation iframe from the background. |
| */ |
| function foregroundNavigation() { |
| navFrame.classList.remove('background'); |
| navFrame.firstChild.tabIndex = 0; |
| navFrame.firstChild.removeAttribute('aria-hidden'); |
| } |
| |
| /** |
| * Enables or disables animated transitions when changing content while |
| * horizontally scrolled. |
| * @param {boolean} enabled True if enabled, else false to disable. |
| */ |
| function setContentChanging(enabled) { |
| navFrame.classList[enabled ? 'add' : 'remove']('changing-content'); |
| |
| if (isRTL()) { |
| uber.invokeMethodOnWindow(navFrame.firstChild.contentWindow, |
| 'setContentChanging', |
| enabled); |
| } |
| } |
| |
| /** |
| * Get an iframe based on the origin of a received post message. |
| * @param {string} origin The origin of a post message. |
| * @return {!HTMLElement} The frame associated to |origin| or null. |
| */ |
| function getIframeFromOrigin(origin) { |
| assert(origin.substr(-1) != '/', 'invalid origin given'); |
| var query = '.iframe-container > iframe[src^="' + origin + '/"]'; |
| return document.querySelector(query); |
| } |
| |
| /** |
| * Changes the path past the page title (i.e. chrome://chrome/settings/(.*)). |
| * @param {string} path The new /path/ to be set after the page name. |
| * @param {number} historyOption The type of history modification to make. |
| */ |
| function changePathTo(path, historyOption) { |
| assert(!path || path.substr(-1) != '/', 'invalid path given'); |
| |
| var histFunc; |
| if (historyOption == HISTORY_STATE_OPTION.PUSH) |
| histFunc = window.history.pushState; |
| else if (historyOption == HISTORY_STATE_OPTION.REPLACE) |
| histFunc = window.history.replaceState; |
| |
| assert(histFunc, 'invalid historyOption given ' + historyOption); |
| |
| var pageId = getSelectedIframe().id; |
| var args = [{pageId: pageId}, '', '/' + pageId + '/' + (path || '')]; |
| histFunc.apply(window.history, args); |
| } |
| |
| /** |
| * Sets the "path" of the page (actually the path after the first '/' char). |
| * @param {Object} origin The origin of the source iframe. |
| * @param {string} title The new "path". |
| */ |
| function setPath(origin, path) { |
| assert(!path || path[0] != '/', 'invalid path sent from ' + origin); |
| // Only update the currently displayed path if this is the visible frame. |
| if (getIframeFromOrigin(origin).parentNode == getSelectedIframe()) |
| changePathTo(path, HISTORY_STATE_OPTION.REPLACE); |
| } |
| |
| /** |
| * Sets the title of the page. |
| * @param {Object} origin The origin of the source iframe. |
| * @param {string} title The title of the page. |
| */ |
| function setTitle(origin, title) { |
| // Cache the title for the client iframe, i.e., the iframe setting the |
| // title. querySelector returns the actual iframe element, so use parentNode |
| // to get back to the container. |
| var container = getIframeFromOrigin(origin).parentNode; |
| container.dataset.title = title; |
| |
| // Only update the currently displayed title if this is the visible frame. |
| if (container == getSelectedIframe()) |
| document.title = title; |
| } |
| |
| /** |
| * Selects a subpage. This is called from uber-frame. |
| * @param {string} pageId Should matche an id of one of the iframe containers. |
| * @param {integer} historyOption Indicates whether we should push or replace |
| * browser history. |
| * @param {string} path A sub-page path. |
| */ |
| function showPage(pageId, historyOption, path) { |
| var container = $(pageId); |
| var lastSelected = document.querySelector('.iframe-container.selected'); |
| |
| // Lazy load of iframe contents. |
| var sourceUrl = container.dataset.url + (path || ''); |
| var frame = container.querySelector('iframe'); |
| if (!frame) { |
| frame = container.ownerDocument.createElement('iframe'); |
| container.appendChild(frame); |
| frame.src = sourceUrl; |
| } else { |
| // There's no particularly good way to know what the current URL of the |
| // content frame is as we don't have access to its contentWindow's |
| // location, so just replace every time until necessary to do otherwise. |
| frame.contentWindow.location.replace(sourceUrl); |
| } |
| |
| // If the last selected container is already showing, ignore the rest. |
| if (lastSelected === container) |
| return; |
| |
| if (lastSelected) { |
| lastSelected.classList.remove('selected'); |
| // Setting aria-hidden hides the container from assistive technology |
| // immediately. The 'hidden' attribute is set after the transition |
| // finishes - that ensures it's not possible to accidentally focus |
| // an element in an unselected container. |
| lastSelected.setAttribute('aria-hidden', 'true'); |
| } |
| |
| // Containers that aren't selected have to be hidden so that their |
| // content isn't focusable. |
| container.hidden = false; |
| container.setAttribute('aria-hidden', 'false'); |
| |
| // Trigger a layout after making it visible and before setting |
| // the class to 'selected', so that it animates in. |
| container.offsetTop; |
| container.classList.add('selected'); |
| |
| setContentChanging(true); |
| adjustToScroll(0); |
| |
| var selectedFrame = getSelectedIframe().querySelector('iframe'); |
| uber.invokeMethodOnWindow(selectedFrame.contentWindow, 'frameSelected'); |
| |
| if (historyOption != HISTORY_STATE_OPTION.NONE) |
| changePathTo(path, historyOption); |
| |
| if (container.dataset.title) |
| document.title = container.dataset.title; |
| $('favicon').href = 'chrome://theme/' + container.dataset.favicon; |
| $('favicon2x').href = 'chrome://theme/' + container.dataset.favicon + '@2x'; |
| |
| updateNavigationControls(); |
| } |
| |
| function onNavigationControlsLoaded() { |
| updateNavigationControls(); |
| } |
| |
| /** |
| * Sends a message to uber-frame to update the appearance of the nav controls. |
| * It should be called whenever the selected iframe changes. |
| */ |
| function updateNavigationControls() { |
| var iframe = getSelectedIframe(); |
| uber.invokeMethodOnWindow(navFrame.firstChild.contentWindow, |
| 'changeSelection', {pageId: iframe.id}); |
| } |
| |
| /** |
| * Forwarded scroll offset from a content frame's scroll handler. |
| * @param {number} scrollOffset The scroll offset from the content frame. |
| */ |
| function adjustToScroll(scrollOffset) { |
| // NOTE: The scroll is reset to 0 and easing turned on every time a user |
| // switches frames. If we receive a non-zero value it has to have come from |
| // a real user scroll, so we disable easing when this happens. |
| if (scrollOffset != 0) |
| setContentChanging(false); |
| |
| if (isRTL()) { |
| uber.invokeMethodOnWindow(navFrame.firstChild.contentWindow, |
| 'adjustToScroll', |
| scrollOffset); |
| var navWidth = Math.max(0, +navFrame.dataset.width + scrollOffset); |
| navFrame.style.width = navWidth + 'px'; |
| } else { |
| navFrame.style.webkitTransform = 'translateX(' + -scrollOffset + 'px)'; |
| } |
| } |
| |
| /** |
| * Forward scroll wheel events to subpages. |
| * @param {Object} params Relevant parameters of wheel event. |
| */ |
| function forwardMouseWheel(params) { |
| var iframe = getSelectedIframe().querySelector('iframe'); |
| uber.invokeMethodOnWindow(iframe.contentWindow, 'mouseWheel', params); |
| } |
| |
| /** |
| * Make sure that iframe containers that are not selected are |
| * hidden, so that elements in those frames aren't part of the |
| * focus order. Containers that are unselected later get hidden |
| * when the transition ends. We also set the aria-hidden attribute |
| * because that hides the container from assistive technology |
| * immediately, rather than only after the transition ends. |
| */ |
| function ensureNonSelectedFrameContainersAreHidden() { |
| var containers = document.querySelectorAll('.iframe-container'); |
| for (var i = 0; i < containers.length; i++) { |
| var container = containers[i]; |
| if (!container.classList.contains('selected')) { |
| container.hidden = true; |
| container.setAttribute('aria-hidden', 'true'); |
| } |
| container.addEventListener('webkitTransitionEnd', function(event) { |
| if (!event.target.classList.contains('selected')) |
| event.target.hidden = true; |
| }); |
| } |
| } |
| |
| return { |
| onLoad: onLoad, |
| onPopHistoryState: onPopHistoryState |
| }; |
| }); |
| |
| window.addEventListener('popstate', uber.onPopHistoryState); |
| document.addEventListener('DOMContentLoaded', uber.onLoad); |