зеркало из https://github.com/mozilla/gecko-dev.git
608 строки
19 KiB
JavaScript
608 строки
19 KiB
JavaScript
// -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/**
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* Import this module through
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*
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* Components.utils.import("resource://gre/modules/SpatialNavigation.jsm");
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*
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* Usage: (Literal class)
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*
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* SpatialNavigation.init(browser_element, optional_callback);
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*
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* optional_callback will be called when a new element is focused.
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*
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* function optional_callback(element) {}
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*/
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"use strict";
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this.EXPORTED_SYMBOLS = ["SpatialNavigation"];
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var SpatialNavigation = {
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init: function(browser, callback) {
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browser.addEventListener("keydown", function (event) {
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_onInputKeyPress(event, callback);
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}, true);
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}
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};
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// Private stuff
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const Cc = Components.classes;
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const Ci = Components.interfaces;
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const Cu = Components.utils;
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Cu["import"]("resource://gre/modules/Services.jsm", this);
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var eventListenerService = Cc["@mozilla.org/eventlistenerservice;1"]
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.getService(Ci.nsIEventListenerService);
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var focusManager = Cc["@mozilla.org/focus-manager;1"]
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.getService(Ci.nsIFocusManager);
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var windowMediator = Cc['@mozilla.org/appshell/window-mediator;1']
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.getService(Ci.nsIWindowMediator);
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// Debug helpers:
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function dump(a) {
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Services.console.logStringMessage("SpatialNavigation: " + a);
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}
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function dumpRect(desc, rect) {
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dump(desc + " " + Math.round(rect.left) + " " + Math.round(rect.top) + " " +
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Math.round(rect.right) + " " + Math.round(rect.bottom) + " width:" +
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Math.round(rect.width) + " height:" + Math.round(rect.height));
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}
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function dumpNodeCoord(desc, node) {
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let rect = node.getBoundingClientRect();
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dump(desc + " " + node.tagName + " x:" + Math.round(rect.left + rect.width/2) +
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" y:" + Math.round(rect.top + rect.height / 2));
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}
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// modifier values
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const kAlt = "alt";
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const kShift = "shift";
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const kCtrl = "ctrl";
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const kNone = "none";
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function _onInputKeyPress (event, callback) {
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//If Spatial Navigation isn't enabled, return.
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if (!PrefObserver['enabled']) {
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return;
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}
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// Use whatever key value is available (either keyCode or charCode).
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// It might be useful for addons or whoever wants to set different
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// key to be used here (e.g. "a", "F1", "arrowUp", ...).
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var key = event.which || event.keyCode;
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if (key != PrefObserver['keyCodeDown'] &&
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key != PrefObserver['keyCodeRight'] &&
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key != PrefObserver['keyCodeUp'] &&
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key != PrefObserver['keyCodeLeft'] &&
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key != PrefObserver['keyCodeReturn']) {
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return;
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}
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if (key == PrefObserver['keyCodeReturn']) {
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// We report presses of the action button on a gamepad "A" as the return
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// key to the DOM. The behaviour of hitting the return key and clicking an
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// element is the same for some elements, but not all, so we handle the
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// ones we want (like the Select element) here:
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if (event.target instanceof Ci.nsIDOMHTMLSelectElement &&
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event.target.click) {
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event.target.click();
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event.stopPropagation();
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event.preventDefault();
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return;
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} else {
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// Leave the action key press to get reported to the DOM as a return
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// keypress.
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return;
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}
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}
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// If it is not using the modifiers it should, return.
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if (!event.altKey && PrefObserver['modifierAlt'] ||
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!event.shiftKey && PrefObserver['modifierShift'] ||
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!event.crtlKey && PrefObserver['modifierCtrl']) {
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return;
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}
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let currentlyFocused = event.target;
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let currentlyFocusedWindow = currentlyFocused.ownerDocument.defaultView;
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let bestElementToFocus = null;
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// If currentlyFocused is an nsIDOMHTMLBodyElement then the page has just been
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// loaded, and this is the first keypress in the page.
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if (currentlyFocused instanceof Ci.nsIDOMHTMLBodyElement) {
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focusManager.moveFocus(currentlyFocusedWindow, null, focusManager.MOVEFOCUS_FIRST, 0);
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event.stopPropagation();
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event.preventDefault();
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return;
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}
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if ((currentlyFocused instanceof Ci.nsIDOMHTMLInputElement &&
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currentlyFocused.mozIsTextField(false)) ||
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currentlyFocused instanceof Ci.nsIDOMHTMLTextAreaElement) {
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// If there is a text selection, remain in the element.
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if (currentlyFocused.selectionEnd - currentlyFocused.selectionStart != 0) {
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return;
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}
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// If there is no text, there is nothing special to do.
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if (currentlyFocused.textLength > 0) {
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if (key == PrefObserver['keyCodeRight'] ||
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key == PrefObserver['keyCodeDown'] ) {
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// We are moving forward into the document.
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if (currentlyFocused.textLength != currentlyFocused.selectionEnd) {
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return;
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}
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} else if (currentlyFocused.selectionStart != 0) {
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return;
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}
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}
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}
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let windowUtils = currentlyFocusedWindow.QueryInterface(Ci.nsIInterfaceRequestor)
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.getInterface(Ci.nsIDOMWindowUtils);
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let cssPageRect = _getRootBounds(windowUtils);
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let searchRect = _getSearchRect(currentlyFocused, key, cssPageRect);
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let nodes = {};
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nodes.length = 0;
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let searchRectOverflows = false;
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while (!bestElementToFocus && !searchRectOverflows) {
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switch (key) {
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case PrefObserver['keyCodeLeft']:
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case PrefObserver['keyCodeRight']: {
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if (searchRect.top < cssPageRect.top &&
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searchRect.bottom > cssPageRect.bottom) {
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searchRectOverflows = true;
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}
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break;
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}
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case PrefObserver['keyCodeUp']:
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case PrefObserver['keyCodeDown']: {
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if (searchRect.left < cssPageRect.left &&
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searchRect.right > cssPageRect.right) {
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searchRectOverflows = true;
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}
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break;
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}
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}
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nodes = windowUtils.nodesFromRect(searchRect.left, searchRect.top,
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0, searchRect.width, searchRect.height, 0,
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true, false);
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// Make the search rectangle "wider": double it's size in the direction
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// that is not the keypress.
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switch (key) {
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case PrefObserver['keyCodeLeft']:
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case PrefObserver['keyCodeRight']: {
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searchRect.top = searchRect.top - (searchRect.height / 2);
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searchRect.bottom = searchRect.top + (searchRect.height * 2);
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searchRect.height = searchRect.height * 2;
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break;
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}
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case PrefObserver['keyCodeUp']:
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case PrefObserver['keyCodeDown']: {
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searchRect.left = searchRect.left - (searchRect.width / 2);
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searchRect.right = searchRect.left + (searchRect.width * 2);
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searchRect.width = searchRect.width * 2;
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break;
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}
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}
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bestElementToFocus = _getBestToFocus(nodes, key, currentlyFocused);
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}
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if (bestElementToFocus === null) {
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// Couldn't find an element to focus.
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return;
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}
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focusManager.setFocus(bestElementToFocus, focusManager.FLAG_SHOWRING);
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//if it is a text element, select all.
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if ((bestElementToFocus instanceof Ci.nsIDOMHTMLInputElement &&
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bestElementToFocus.mozIsTextField(false)) ||
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bestElementToFocus instanceof Ci.nsIDOMHTMLTextAreaElement) {
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bestElementToFocus.selectionStart = 0;
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bestElementToFocus.selectionEnd = bestElementToFocus.textLength;
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}
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if (callback != undefined) {
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callback(bestElementToFocus);
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}
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event.preventDefault();
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event.stopPropagation();
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}
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// Returns the bounds of the page relative to the viewport.
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function _getRootBounds(windowUtils) {
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let cssPageRect = windowUtils.getRootBounds();
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let scrollX = {};
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let scrollY = {};
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windowUtils.getScrollXY(false, scrollX, scrollY);
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let cssPageRectCopy = {};
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cssPageRectCopy.right = cssPageRect.right - scrollX.value;
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cssPageRectCopy.left = cssPageRect.left - scrollX.value;
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cssPageRectCopy.top = cssPageRect.top - scrollY.value;
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cssPageRectCopy.bottom = cssPageRect.bottom - scrollY.value;
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cssPageRectCopy.width = cssPageRect.width;
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cssPageRectCopy.height = cssPageRect.height;
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return cssPageRectCopy;
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}
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// Returns the best node to focus from the list of nodes returned by the hit
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// test.
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function _getBestToFocus(nodes, key, currentlyFocused) {
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let best = null;
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let bestDist;
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let bestMid;
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let nodeMid;
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let currentlyFocusedMid = _getMidpoint(currentlyFocused);
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let currentlyFocusedRect = currentlyFocused.getBoundingClientRect();
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for (let i = 0; i < nodes.length; i++) {
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// Reject the currentlyFocused, and all node types we can't focus
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if (!_canFocus(nodes[i]) || nodes[i] === currentlyFocused) {
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continue;
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}
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// Reject all nodes that aren't "far enough" in the direction of the
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// keypress
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nodeMid = _getMidpoint(nodes[i]);
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switch (key) {
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case PrefObserver['keyCodeLeft']:
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if (nodeMid.x >= (currentlyFocusedMid.x - currentlyFocusedRect.width / 2)) {
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continue;
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}
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break;
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case PrefObserver['keyCodeRight']:
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if (nodeMid.x <= (currentlyFocusedMid.x + currentlyFocusedRect.width / 2)) {
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continue;
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}
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break;
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case PrefObserver['keyCodeUp']:
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if (nodeMid.y >= (currentlyFocusedMid.y - currentlyFocusedRect.height / 2)) {
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continue;
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}
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break;
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case PrefObserver['keyCodeDown']:
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if (nodeMid.y <= (currentlyFocusedMid.y + currentlyFocusedRect.height / 2)) {
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continue;
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}
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break;
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}
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// Initialize best to the first viable value:
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if (!best) {
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bestDist = _spatialDistanceOfCorner(currentlyFocused, nodes[i], key);
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if (bestDist >= 0) {
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best = nodes[i];
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}
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continue;
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}
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// Of the remaining nodes, pick the one closest to the currently focused
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// node.
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let curDist = _spatialDistanceOfCorner(currentlyFocused, nodes[i], key);
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if ((curDist > bestDist) || curDist === -1) {
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continue;
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}
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else if (curDist === bestDist) {
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let midCurDist = _spatialDistance(currentlyFocused, nodes[i]);
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let midBestDist = _spatialDistance(currentlyFocused, best);
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if (midCurDist > midBestDist)
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continue;
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}
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best = nodes[i];
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bestDist = curDist;
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}
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return best;
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}
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// Returns the midpoint of a node.
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function _getMidpoint(node) {
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let mid = {};
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let box = node.getBoundingClientRect();
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mid.x = box.left + (box.width / 2);
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mid.y = box.top + (box.height / 2);
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return mid;
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}
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// Returns true if the node is a type that we want to focus, false otherwise.
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function _canFocus(node) {
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if (node instanceof Ci.nsIDOMHTMLLinkElement ||
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node instanceof Ci.nsIDOMHTMLAnchorElement) {
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return true;
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}
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if ((node instanceof Ci.nsIDOMHTMLButtonElement ||
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node instanceof Ci.nsIDOMHTMLInputElement ||
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node instanceof Ci.nsIDOMHTMLLinkElement ||
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node instanceof Ci.nsIDOMHTMLOptGroupElement ||
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node instanceof Ci.nsIDOMHTMLSelectElement ||
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node instanceof Ci.nsIDOMHTMLTextAreaElement) &&
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node.disabled === false) {
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return true;
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}
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return false;
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}
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// Returns a rectangle that extends to the end of the screen in the direction that
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// the key is pressed.
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function _getSearchRect(currentlyFocused, key, cssPageRect) {
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let currentlyFocusedRect = currentlyFocused.getBoundingClientRect();
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let newRect = {};
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newRect.left = currentlyFocusedRect.left;
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newRect.top = currentlyFocusedRect.top;
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newRect.right = currentlyFocusedRect.right;
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newRect.bottom = currentlyFocusedRect.bottom;
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newRect.width = currentlyFocusedRect.width;
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newRect.height = currentlyFocusedRect.height;
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switch (key) {
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case PrefObserver['keyCodeLeft']:
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newRect.right = newRect.left;
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newRect.left = cssPageRect.left;
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newRect.width = newRect.right - newRect.left;
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newRect.bottom = cssPageRect.bottom;
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newRect.top = cssPageRect.top;
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newRect.height = newRect.bottom - newRect.top;
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break;
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case PrefObserver['keyCodeRight']:
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newRect.left = newRect.right;
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newRect.right = cssPageRect.right;
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newRect.width = newRect.right - newRect.left;
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newRect.bottom = cssPageRect.bottom;
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newRect.top = cssPageRect.top;
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newRect.height = newRect.bottom - newRect.top;
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break;
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case PrefObserver['keyCodeUp']:
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newRect.bottom = newRect.top;
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newRect.top = cssPageRect.top;
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newRect.height = newRect.bottom - newRect.top;
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newRect.right = cssPageRect.right;
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newRect.left = cssPageRect.left;
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newRect.width = newRect.right - newRect.left;
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break;
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case PrefObserver['keyCodeDown']:
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newRect.top = newRect.bottom;
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newRect.bottom = cssPageRect.bottom;
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newRect.height = newRect.bottom - newRect.top;
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newRect.right = cssPageRect.right;
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newRect.left = cssPageRect.left;
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newRect.width = newRect.right - newRect.left;
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break;
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}
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return newRect;
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}
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// Gets the distance between two points a and b.
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function _spatialDistance(a, b) {
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let mida = _getMidpoint(a);
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let midb = _getMidpoint(b);
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return Math.round(Math.pow(mida.x - midb.x, 2) +
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Math.pow(mida.y - midb.y, 2));
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}
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// Get the distance between the corner of two nodes
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function _spatialDistanceOfCorner(from, to, key) {
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let fromRect = from.getBoundingClientRect();
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let toRect = to.getBoundingClientRect();
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let fromMid = _getMidpoint(from);
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let toMid = _getMidpoint(to);
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let hDistance = 0;
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let vDistance = 0;
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switch (key) {
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case PrefObserver['keyCodeLeft']:
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// Make sure the "to" node is really at the left side of "from" node by
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// 1. Check the mid point
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// 2. The right border of "to" node must be less than the "from" node
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if ((fromMid.x - toMid.x) < 0 || toRect.right >= fromRect.right)
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return -1;
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hDistance = Math.abs(fromRect.left - toRect.right);
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if (toRect.bottom <= fromRect.top) {
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vDistance = fromRect.top - toRect.bottom;
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}
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else if (fromRect.bottom <= toRect.top) {
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vDistance = toRect.top - fromRect.bottom;
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}
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else {
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vDistance = 0;
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}
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break;
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case PrefObserver['keyCodeRight']:
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if ((toMid.x - fromMid.x) < 0 || toRect.left <= fromRect.left)
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return -1;
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hDistance = Math.abs(toRect.left - fromRect.right);
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if (toRect.bottom <= fromRect.top) {
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vDistance = fromRect.top - toRect.bottom;
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}
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else if (fromRect.bottom <= toRect.top) {
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vDistance = toRect.top - fromRect.bottom;
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}
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else {
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vDistance = 0;
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}
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break;
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case PrefObserver['keyCodeUp']:
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if ((fromMid.y - toMid.y) < 0 || toRect.bottom >= fromRect.bottom)
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return -1;
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vDistance = Math.abs(fromRect.top - toRect.bottom);
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if (fromRect.right <= toRect.left) {
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hDistance = toRect.left - fromRect.right;
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}
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else if (toRect.right <= fromRect.left) {
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hDistance = fromRect.left - toRect.right;
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}
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else {
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hDistance = 0;
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}
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break;
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case PrefObserver['keyCodeDown']:
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if ((toMid.y - fromMid.y) < 0 || toRect.top <= fromRect.top)
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return -1;
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vDistance = Math.abs(toRect.top - fromRect.bottom);
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if (fromRect.right <= toRect.left) {
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hDistance = toRect.left - fromRect.right;
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}
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else if (toRect.right <= fromRect.left) {
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hDistance = fromRect.left - toRect.right;
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}
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else {
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hDistance = 0;
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}
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break;
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}
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return Math.round(Math.pow(hDistance, 2) +
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Math.pow(vDistance, 2));
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}
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// Snav preference observer
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var PrefObserver = {
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register: function() {
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this.prefService = Cc["@mozilla.org/preferences-service;1"]
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.getService(Ci.nsIPrefService);
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this._branch = this.prefService.getBranch("snav.");
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this._branch.QueryInterface(Ci.nsIPrefBranch2);
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this._branch.addObserver("", this, false);
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// set current or default pref values
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this.observe(null, "nsPref:changed", "enabled");
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this.observe(null, "nsPref:changed", "xulContentEnabled");
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this.observe(null, "nsPref:changed", "keyCode.modifier");
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this.observe(null, "nsPref:changed", "keyCode.right");
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this.observe(null, "nsPref:changed", "keyCode.up");
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this.observe(null, "nsPref:changed", "keyCode.down");
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this.observe(null, "nsPref:changed", "keyCode.left");
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this.observe(null, "nsPref:changed", "keyCode.return");
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},
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observe: function(aSubject, aTopic, aData) {
|
|
if (aTopic != "nsPref:changed") {
|
|
return;
|
|
}
|
|
|
|
// aSubject is the nsIPrefBranch we're observing (after appropriate QI)
|
|
// aData is the name of the pref that's been changed (relative to aSubject)
|
|
switch (aData) {
|
|
case "enabled":
|
|
try {
|
|
this.enabled = this._branch.getBoolPref("enabled");
|
|
} catch(e) {
|
|
this.enabled = false;
|
|
}
|
|
break;
|
|
|
|
case "xulContentEnabled":
|
|
try {
|
|
this.xulContentEnabled = this._branch.getBoolPref("xulContentEnabled");
|
|
} catch(e) {
|
|
this.xulContentEnabled = false;
|
|
}
|
|
break;
|
|
|
|
case "keyCode.modifier": {
|
|
let keyCodeModifier;
|
|
try {
|
|
keyCodeModifier = this._branch.getCharPref("keyCode.modifier");
|
|
|
|
// resetting modifiers
|
|
this.modifierAlt = false;
|
|
this.modifierShift = false;
|
|
this.modifierCtrl = false;
|
|
|
|
if (keyCodeModifier != this.kNone) {
|
|
// we are using '+' as a separator in about:config.
|
|
let mods = keyCodeModifier.split(/\++/);
|
|
for (let i = 0; i < mods.length; i++) {
|
|
let mod = mods[i].toLowerCase();
|
|
if (mod === "")
|
|
continue;
|
|
else if (mod == kAlt)
|
|
this.modifierAlt = true;
|
|
else if (mod == kShift)
|
|
this.modifierShift = true;
|
|
else if (mod == kCtrl)
|
|
this.modifierCtrl = true;
|
|
else {
|
|
keyCodeModifier = kNone;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
} catch(e) { }
|
|
break;
|
|
}
|
|
|
|
case "keyCode.up":
|
|
try {
|
|
this.keyCodeUp = this._branch.getIntPref("keyCode.up");
|
|
} catch(e) {
|
|
this.keyCodeUp = Ci.nsIDOMKeyEvent.DOM_VK_UP;
|
|
}
|
|
break;
|
|
case "keyCode.down":
|
|
try {
|
|
this.keyCodeDown = this._branch.getIntPref("keyCode.down");
|
|
} catch(e) {
|
|
this.keyCodeDown = Ci.nsIDOMKeyEvent.DOM_VK_DOWN;
|
|
}
|
|
break;
|
|
case "keyCode.left":
|
|
try {
|
|
this.keyCodeLeft = this._branch.getIntPref("keyCode.left");
|
|
} catch(e) {
|
|
this.keyCodeLeft = Ci.nsIDOMKeyEvent.DOM_VK_LEFT;
|
|
}
|
|
break;
|
|
case "keyCode.right":
|
|
try {
|
|
this.keyCodeRight = this._branch.getIntPref("keyCode.right");
|
|
} catch(e) {
|
|
this.keyCodeRight = Ci.nsIDOMKeyEvent.DOM_VK_RIGHT;
|
|
}
|
|
break;
|
|
case "keyCode.return":
|
|
try {
|
|
this.keyCodeReturn = this._branch.getIntPref("keyCode.return");
|
|
} catch(e) {
|
|
this.keyCodeReturn = Ci.nsIDOMKeyEvent.DOM_VK_RETURN;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
};
|
|
|
|
PrefObserver.register();
|