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Diffstat (limited to 'accessible/jsat/EventManager.jsm')
| -rw-r--r-- | accessible/jsat/EventManager.jsm | 723 |
1 files changed, 723 insertions, 0 deletions
diff --git a/accessible/jsat/EventManager.jsm b/accessible/jsat/EventManager.jsm new file mode 100644 index 000000000..4d635eb68 --- /dev/null +++ b/accessible/jsat/EventManager.jsm @@ -0,0 +1,723 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +'use strict'; + +const Ci = Components.interfaces; +const Cu = Components.utils; + +const TEXT_NODE = 3; + +Cu.import('resource://gre/modules/XPCOMUtils.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Services', + 'resource://gre/modules/Services.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Utils', + 'resource://gre/modules/accessibility/Utils.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Logger', + 'resource://gre/modules/accessibility/Utils.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Presentation', + 'resource://gre/modules/accessibility/Presentation.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Roles', + 'resource://gre/modules/accessibility/Constants.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'Events', + 'resource://gre/modules/accessibility/Constants.jsm'); +XPCOMUtils.defineLazyModuleGetter(this, 'States', + 'resource://gre/modules/accessibility/Constants.jsm'); + +this.EXPORTED_SYMBOLS = ['EventManager']; + +this.EventManager = function EventManager(aContentScope, aContentControl) { + this.contentScope = aContentScope; + this.contentControl = aContentControl; + this.addEventListener = this.contentScope.addEventListener.bind( + this.contentScope); + this.removeEventListener = this.contentScope.removeEventListener.bind( + this.contentScope); + this.sendMsgFunc = this.contentScope.sendAsyncMessage.bind( + this.contentScope); + this.webProgress = this.contentScope.docShell. + QueryInterface(Ci.nsIInterfaceRequestor). + getInterface(Ci.nsIWebProgress); +}; + +this.EventManager.prototype = { + editState: { editing: false }, + + start: function start() { + try { + if (!this._started) { + Logger.debug('EventManager.start'); + + this._started = true; + + AccessibilityEventObserver.addListener(this); + + this.webProgress.addProgressListener(this, + (Ci.nsIWebProgress.NOTIFY_STATE_ALL | + Ci.nsIWebProgress.NOTIFY_LOCATION)); + this.addEventListener('wheel', this, true); + this.addEventListener('scroll', this, true); + this.addEventListener('resize', this, true); + this._preDialogPosition = new WeakMap(); + } + this.present(Presentation.tabStateChanged(null, 'newtab')); + + } catch (x) { + Logger.logException(x, 'Failed to start EventManager'); + } + }, + + // XXX: Stop is not called when the tab is closed (|TabClose| event is too + // late). It is only called when the AccessFu is disabled explicitly. + stop: function stop() { + if (!this._started) { + return; + } + Logger.debug('EventManager.stop'); + AccessibilityEventObserver.removeListener(this); + try { + this._preDialogPosition = new WeakMap(); + this.webProgress.removeProgressListener(this); + this.removeEventListener('wheel', this, true); + this.removeEventListener('scroll', this, true); + this.removeEventListener('resize', this, true); + } catch (x) { + // contentScope is dead. + } finally { + this._started = false; + } + }, + + handleEvent: function handleEvent(aEvent) { + Logger.debug(() => { + return ['DOMEvent', aEvent.type]; + }); + + try { + switch (aEvent.type) { + case 'wheel': + { + let attempts = 0; + let delta = aEvent.deltaX || aEvent.deltaY; + this.contentControl.autoMove( + null, + { moveMethod: delta > 0 ? 'moveNext' : 'movePrevious', + onScreenOnly: true, noOpIfOnScreen: true, delay: 500 }); + break; + } + case 'scroll': + case 'resize': + { + // the target could be an element, document or window + let window = null; + if (aEvent.target instanceof Ci.nsIDOMWindow) + window = aEvent.target; + else if (aEvent.target instanceof Ci.nsIDOMDocument) + window = aEvent.target.defaultView; + else if (aEvent.target instanceof Ci.nsIDOMElement) + window = aEvent.target.ownerDocument.defaultView; + this.present(Presentation.viewportChanged(window)); + break; + } + } + } catch (x) { + Logger.logException(x, 'Error handling DOM event'); + } + }, + + handleAccEvent: function handleAccEvent(aEvent) { + Logger.debug(() => { + return ['A11yEvent', Logger.eventToString(aEvent), + Logger.accessibleToString(aEvent.accessible)]; + }); + + // Don't bother with non-content events in firefox. + if (Utils.MozBuildApp == 'browser' && + aEvent.eventType != Events.VIRTUALCURSOR_CHANGED && + // XXX Bug 442005 results in DocAccessible::getDocType returning + // NS_ERROR_FAILURE. Checking for aEvent.accessibleDocument.docType == + // 'window' does not currently work. + (aEvent.accessibleDocument.DOMDocument.doctype && + aEvent.accessibleDocument.DOMDocument.doctype.name === 'window')) { + return; + } + + switch (aEvent.eventType) { + case Events.VIRTUALCURSOR_CHANGED: + { + let pivot = aEvent.accessible. + QueryInterface(Ci.nsIAccessibleDocument).virtualCursor; + let position = pivot.position; + if (position && position.role == Roles.INTERNAL_FRAME) + break; + let event = aEvent. + QueryInterface(Ci.nsIAccessibleVirtualCursorChangeEvent); + let reason = event.reason; + let oldAccessible = event.oldAccessible; + + if (this.editState.editing && + !Utils.getState(position).contains(States.FOCUSED)) { + aEvent.accessibleDocument.takeFocus(); + } + this.present( + Presentation.pivotChanged(position, oldAccessible, reason, + pivot.startOffset, pivot.endOffset, + aEvent.isFromUserInput)); + + break; + } + case Events.STATE_CHANGE: + { + let event = aEvent.QueryInterface(Ci.nsIAccessibleStateChangeEvent); + let state = Utils.getState(event); + if (state.contains(States.CHECKED)) { + if (aEvent.accessible.role === Roles.SWITCH) { + this.present( + Presentation. + actionInvoked(aEvent.accessible, + event.isEnabled ? 'on' : 'off')); + } else { + this.present( + Presentation. + actionInvoked(aEvent.accessible, + event.isEnabled ? 'check' : 'uncheck')); + } + } else if (state.contains(States.SELECTED)) { + this.present( + Presentation. + actionInvoked(aEvent.accessible, + event.isEnabled ? 'select' : 'unselect')); + } + break; + } + case Events.NAME_CHANGE: + { + let acc = aEvent.accessible; + if (acc === this.contentControl.vc.position) { + this.present(Presentation.nameChanged(acc)); + } else { + let {liveRegion, isPolite} = this._handleLiveRegion(aEvent, + ['text', 'all']); + if (liveRegion) { + this.present(Presentation.nameChanged(acc, isPolite)); + } + } + break; + } + case Events.SCROLLING_START: + { + this.contentControl.autoMove(aEvent.accessible); + break; + } + case Events.TEXT_CARET_MOVED: + { + let acc = aEvent.accessible.QueryInterface(Ci.nsIAccessibleText); + let caretOffset = aEvent. + QueryInterface(Ci.nsIAccessibleCaretMoveEvent).caretOffset; + + // We could get a caret move in an accessible that is not focused, + // it doesn't mean we are not on any editable accessible. just not + // on this one.. + let state = Utils.getState(acc); + if (state.contains(States.FOCUSED)) { + this._setEditingMode(aEvent, caretOffset); + if (state.contains(States.EDITABLE)) { + this.present(Presentation.textSelectionChanged(acc.getText(0, -1), + caretOffset, caretOffset, 0, 0, aEvent.isFromUserInput)); + } + } + break; + } + case Events.OBJECT_ATTRIBUTE_CHANGED: + { + let evt = aEvent.QueryInterface( + Ci.nsIAccessibleObjectAttributeChangedEvent); + if (evt.changedAttribute.toString() !== 'aria-hidden') { + // Only handle aria-hidden attribute change. + break; + } + let hidden = Utils.isHidden(aEvent.accessible); + this[hidden ? '_handleHide' : '_handleShow'](evt); + if (this.inTest) { + this.sendMsgFunc("AccessFu:AriaHidden", { hidden: hidden }); + } + break; + } + case Events.SHOW: + { + this._handleShow(aEvent); + break; + } + case Events.HIDE: + { + let evt = aEvent.QueryInterface(Ci.nsIAccessibleHideEvent); + this._handleHide(evt); + break; + } + case Events.TEXT_INSERTED: + case Events.TEXT_REMOVED: + { + let {liveRegion, isPolite} = this._handleLiveRegion(aEvent, + ['text', 'all']); + if (aEvent.isFromUserInput || liveRegion) { + // Handle all text mutations coming from the user or if they happen + // on a live region. + this._handleText(aEvent, liveRegion, isPolite); + } + break; + } + case Events.FOCUS: + { + // Put vc where the focus is at + let acc = aEvent.accessible; + let doc = aEvent.accessibleDocument; + this._setEditingMode(aEvent); + if ([Roles.CHROME_WINDOW, + Roles.DOCUMENT, + Roles.APPLICATION].indexOf(acc.role) < 0) { + this.contentControl.autoMove(acc); + } + + if (this.inTest) { + this.sendMsgFunc("AccessFu:Focused"); + } + break; + } + case Events.DOCUMENT_LOAD_COMPLETE: + { + let position = this.contentControl.vc.position; + // Check if position is in the subtree of the DOCUMENT_LOAD_COMPLETE + // event's dialog accesible or accessible document + let subtreeRoot = aEvent.accessible.role === Roles.DIALOG ? + aEvent.accessible : aEvent.accessibleDocument; + if (aEvent.accessible === aEvent.accessibleDocument || + (position && Utils.isInSubtree(position, subtreeRoot))) { + // Do not automove into the document if the virtual cursor is already + // positioned inside it. + break; + } + this._preDialogPosition.set(aEvent.accessible.DOMNode, position); + this.contentControl.autoMove(aEvent.accessible, { delay: 500 }); + break; + } + case Events.VALUE_CHANGE: + case Events.TEXT_VALUE_CHANGE: + { + let position = this.contentControl.vc.position; + let target = aEvent.accessible; + if (position === target || + Utils.getEmbeddedControl(position) === target) { + this.present(Presentation.valueChanged(target)); + } else { + let {liveRegion, isPolite} = this._handleLiveRegion(aEvent, + ['text', 'all']); + if (liveRegion) { + this.present(Presentation.valueChanged(target, isPolite)); + } + } + } + } + }, + + _setEditingMode: function _setEditingMode(aEvent, aCaretOffset) { + let acc = aEvent.accessible; + let accText, characterCount; + let caretOffset = aCaretOffset; + + try { + accText = acc.QueryInterface(Ci.nsIAccessibleText); + } catch (e) { + // No text interface on this accessible. + } + + if (accText) { + characterCount = accText.characterCount; + if (caretOffset === undefined) { + caretOffset = accText.caretOffset; + } + } + + // Update editing state, both for presenter and other things + let state = Utils.getState(acc); + + let editState = { + editing: state.contains(States.EDITABLE) && + state.contains(States.FOCUSED), + multiline: state.contains(States.MULTI_LINE), + atStart: caretOffset === 0, + atEnd: caretOffset === characterCount + }; + + // Not interesting + if (!editState.editing && editState.editing === this.editState.editing) { + return; + } + + if (editState.editing !== this.editState.editing) { + this.present(Presentation.editingModeChanged(editState.editing)); + } + + if (editState.editing !== this.editState.editing || + editState.multiline !== this.editState.multiline || + editState.atEnd !== this.editState.atEnd || + editState.atStart !== this.editState.atStart) { + this.sendMsgFunc("AccessFu:Input", editState); + } + + this.editState = editState; + }, + + _handleShow: function _handleShow(aEvent) { + let {liveRegion, isPolite} = this._handleLiveRegion(aEvent, + ['additions', 'all']); + // Only handle show if it is a relevant live region. + if (!liveRegion) { + return; + } + // Show for text is handled by the EVENT_TEXT_INSERTED handler. + if (aEvent.accessible.role === Roles.TEXT_LEAF) { + return; + } + this._dequeueLiveEvent(Events.HIDE, liveRegion); + this.present(Presentation.liveRegion(liveRegion, isPolite, false)); + }, + + _handleHide: function _handleHide(aEvent) { + let {liveRegion, isPolite} = this._handleLiveRegion( + aEvent, ['removals', 'all']); + let acc = aEvent.accessible; + if (liveRegion) { + // Hide for text is handled by the EVENT_TEXT_REMOVED handler. + if (acc.role === Roles.TEXT_LEAF) { + return; + } + this._queueLiveEvent(Events.HIDE, liveRegion, isPolite); + } else { + let vc = Utils.getVirtualCursor(this.contentScope.content.document); + if (vc.position && + (Utils.getState(vc.position).contains(States.DEFUNCT) || + Utils.isInSubtree(vc.position, acc))) { + let position = this._preDialogPosition.get(aEvent.accessible.DOMNode) || + aEvent.targetPrevSibling || aEvent.targetParent; + if (!position) { + try { + position = acc.previousSibling; + } catch (x) { + // Accessible is unattached from the accessible tree. + position = acc.parent; + } + } + this.contentControl.autoMove(position, + { moveToFocused: true, delay: 500 }); + } + } + }, + + _handleText: function _handleText(aEvent, aLiveRegion, aIsPolite) { + let event = aEvent.QueryInterface(Ci.nsIAccessibleTextChangeEvent); + let isInserted = event.isInserted; + let txtIface = aEvent.accessible.QueryInterface(Ci.nsIAccessibleText); + + let text = ''; + try { + text = txtIface.getText(0, Ci.nsIAccessibleText.TEXT_OFFSET_END_OF_TEXT); + } catch (x) { + // XXX we might have gotten an exception with of a + // zero-length text. If we did, ignore it (bug #749810). + if (txtIface.characterCount) { + throw x; + } + } + // If there are embedded objects in the text, ignore them. + // Assuming changes to the descendants would already be handled by the + // show/hide event. + let modifiedText = event.modifiedText.replace(/\uFFFC/g, ''); + if (modifiedText != event.modifiedText && !modifiedText.trim()) { + return; + } + + if (aLiveRegion) { + if (aEvent.eventType === Events.TEXT_REMOVED) { + this._queueLiveEvent(Events.TEXT_REMOVED, aLiveRegion, aIsPolite, + modifiedText); + } else { + this._dequeueLiveEvent(Events.TEXT_REMOVED, aLiveRegion); + this.present(Presentation.liveRegion(aLiveRegion, aIsPolite, false, + modifiedText)); + } + } else { + this.present(Presentation.textChanged(aEvent.accessible, isInserted, + event.start, event.length, text, modifiedText)); + } + }, + + _handleLiveRegion: function _handleLiveRegion(aEvent, aRelevant) { + if (aEvent.isFromUserInput) { + return {}; + } + let parseLiveAttrs = function parseLiveAttrs(aAccessible) { + let attrs = Utils.getAttributes(aAccessible); + if (attrs['container-live']) { + return { + live: attrs['container-live'], + relevant: attrs['container-relevant'] || 'additions text', + busy: attrs['container-busy'], + atomic: attrs['container-atomic'], + memberOf: attrs['member-of'] + }; + } + return null; + }; + // XXX live attributes are not set for hidden accessibles yet. Need to + // climb up the tree to check for them. + let getLiveAttributes = function getLiveAttributes(aEvent) { + let liveAttrs = parseLiveAttrs(aEvent.accessible); + if (liveAttrs) { + return liveAttrs; + } + let parent = aEvent.targetParent; + while (parent) { + liveAttrs = parseLiveAttrs(parent); + if (liveAttrs) { + return liveAttrs; + } + parent = parent.parent + } + return {}; + }; + let {live, relevant, busy, atomic, memberOf} = getLiveAttributes(aEvent); + // If container-live is not present or is set to |off| ignore the event. + if (!live || live === 'off') { + return {}; + } + // XXX: support busy and atomic. + + // Determine if the type of the mutation is relevant. Default is additions + // and text. + let isRelevant = Utils.matchAttributeValue(relevant, aRelevant); + if (!isRelevant) { + return {}; + } + return { + liveRegion: aEvent.accessible, + isPolite: live === 'polite' + }; + }, + + _dequeueLiveEvent: function _dequeueLiveEvent(aEventType, aLiveRegion) { + let domNode = aLiveRegion.DOMNode; + if (this._liveEventQueue && this._liveEventQueue.has(domNode)) { + let queue = this._liveEventQueue.get(domNode); + let nextEvent = queue[0]; + if (nextEvent.eventType === aEventType) { + Utils.win.clearTimeout(nextEvent.timeoutID); + queue.shift(); + if (queue.length === 0) { + this._liveEventQueue.delete(domNode) + } + } + } + }, + + _queueLiveEvent: function _queueLiveEvent(aEventType, aLiveRegion, aIsPolite, aModifiedText) { + if (!this._liveEventQueue) { + this._liveEventQueue = new WeakMap(); + } + let eventHandler = { + eventType: aEventType, + timeoutID: Utils.win.setTimeout(this.present.bind(this), + 20, // Wait for a possible EVENT_SHOW or EVENT_TEXT_INSERTED event. + Presentation.liveRegion(aLiveRegion, aIsPolite, true, aModifiedText)) + }; + + let domNode = aLiveRegion.DOMNode; + if (this._liveEventQueue.has(domNode)) { + this._liveEventQueue.get(domNode).push(eventHandler); + } else { + this._liveEventQueue.set(domNode, [eventHandler]); + } + }, + + present: function present(aPresentationData) { + this.sendMsgFunc("AccessFu:Present", aPresentationData); + }, + + onStateChange: function onStateChange(aWebProgress, aRequest, aStateFlags, aStatus) { + let tabstate = ''; + + let loadingState = Ci.nsIWebProgressListener.STATE_TRANSFERRING | + Ci.nsIWebProgressListener.STATE_IS_DOCUMENT; + let loadedState = Ci.nsIWebProgressListener.STATE_STOP | + Ci.nsIWebProgressListener.STATE_IS_NETWORK; + + if ((aStateFlags & loadingState) == loadingState) { + tabstate = 'loading'; + } else if ((aStateFlags & loadedState) == loadedState && + !aWebProgress.isLoadingDocument) { + tabstate = 'loaded'; + } + + if (tabstate) { + let docAcc = Utils.AccService.getAccessibleFor(aWebProgress.DOMWindow.document); + this.present(Presentation.tabStateChanged(docAcc, tabstate)); + } + }, + + onProgressChange: function onProgressChange() {}, + + onLocationChange: function onLocationChange(aWebProgress, aRequest, aLocation, aFlags) { + let docAcc = Utils.AccService.getAccessibleFor(aWebProgress.DOMWindow.document); + this.present(Presentation.tabStateChanged(docAcc, 'newdoc')); + }, + + onStatusChange: function onStatusChange() {}, + + onSecurityChange: function onSecurityChange() {}, + + QueryInterface: XPCOMUtils.generateQI([Ci.nsIWebProgressListener, + Ci.nsISupportsWeakReference, + Ci.nsISupports, + Ci.nsIObserver]) +}; + +const AccessibilityEventObserver = { + + /** + * A WeakMap containing [content, EventManager] pairs. + */ + eventManagers: new WeakMap(), + + /** + * A total number of registered eventManagers. + */ + listenerCount: 0, + + /** + * An indicator of an active 'accessible-event' observer. + */ + started: false, + + /** + * Start an AccessibilityEventObserver. + */ + start: function start() { + if (this.started || this.listenerCount === 0) { + return; + } + Services.obs.addObserver(this, 'accessible-event', false); + this.started = true; + }, + + /** + * Stop an AccessibilityEventObserver. + */ + stop: function stop() { + if (!this.started) { + return; + } + Services.obs.removeObserver(this, 'accessible-event'); + // Clean up all registered event managers. + this.eventManagers = new WeakMap(); + this.listenerCount = 0; + this.started = false; + }, + + /** + * Register an EventManager and start listening to the + * 'accessible-event' messages. + * + * @param aEventManager EventManager + * An EventManager object that was loaded into the specific content. + */ + addListener: function addListener(aEventManager) { + let content = aEventManager.contentScope.content; + if (!this.eventManagers.has(content)) { + this.listenerCount++; + } + this.eventManagers.set(content, aEventManager); + // Since at least one EventManager was registered, start listening. + Logger.debug('AccessibilityEventObserver.addListener. Total:', + this.listenerCount); + this.start(); + }, + + /** + * Unregister an EventManager and, optionally, stop listening to the + * 'accessible-event' messages. + * + * @param aEventManager EventManager + * An EventManager object that was stopped in the specific content. + */ + removeListener: function removeListener(aEventManager) { + let content = aEventManager.contentScope.content; + if (!this.eventManagers.delete(content)) { + return; + } + this.listenerCount--; + Logger.debug('AccessibilityEventObserver.removeListener. Total:', + this.listenerCount); + if (this.listenerCount === 0) { + // If there are no EventManagers registered at the moment, stop listening + // to the 'accessible-event' messages. + this.stop(); + } + }, + + /** + * Lookup an EventManager for a specific content. If the EventManager is not + * found, walk up the hierarchy of parent windows. + * @param content Window + * A content Window used to lookup the corresponding EventManager. + */ + getListener: function getListener(content) { + let eventManager = this.eventManagers.get(content); + if (eventManager) { + return eventManager; + } + let parent = content.parent; + if (parent === content) { + // There is no parent or the parent is of a different type. + return null; + } + return this.getListener(parent); + }, + + /** + * Handle the 'accessible-event' message. + */ + observe: function observe(aSubject, aTopic, aData) { + if (aTopic !== 'accessible-event') { + return; + } + let event = aSubject.QueryInterface(Ci.nsIAccessibleEvent); + if (!event.accessibleDocument) { + Logger.warning( + 'AccessibilityEventObserver.observe: no accessible document:', + Logger.eventToString(event), "accessible:", + Logger.accessibleToString(event.accessible)); + return; + } + let content = event.accessibleDocument.window; + // Match the content window to its EventManager. + let eventManager = this.getListener(content); + if (!eventManager || !eventManager._started) { + if (Utils.MozBuildApp === 'browser' && + !(content instanceof Ci.nsIDOMChromeWindow)) { + Logger.warning( + 'AccessibilityEventObserver.observe: ignored event:', + Logger.eventToString(event), "accessible:", + Logger.accessibleToString(event.accessible), "document:", + Logger.accessibleToString(event.accessibleDocument)); + } + return; + } + try { + eventManager.handleAccEvent(event); + } catch (x) { + Logger.logException(x, 'Error handing accessible event'); + } finally { + return; + } + } +}; |