Quelle accessibility.js Sprache: JAVA

/* 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";

loader.lazyRequireGetter(
  this,
  ["loadSheet", "removeSheet"],
  "resource://devtools/shared/layout/utils.js",
  true
);

// Highlighter style used for preventing transitions and applying transparency
// when calculating colour contrast.
const HIGHLIGHTER_STYLES_SHEET = `data:text/css;charset=utf-8,
* {
  transition: initial !important;
}

:-moz-devtools-highlighted {
  color: transparent !important;
  text-shadow: none !important;
}`;

/**
* Helper function that determines if nsIAccessible object is in defunct state.
*
* @param  {nsIAccessible}  accessible
*         object to be tested.
* @return {Boolean}
*         True if accessible object is defunct, false otherwise.
*/
function isDefunct(accessible) {
  // If accessibility is disabled, safely assume that the accessible object is
  // now dead.
  if (!Services.appinfo.accessibilityEnabled) {
    return true;
  }

  let defunct = false;

  try {
    const extraState = {};
    accessible.getState({}, extraState);
    // extraState.value is a bitmask. We are applying bitwise AND to mask out
    // irrelevant states.
    defunct = !!(extraState.value & Ci.nsIAccessibleStates.EXT_STATE_DEFUNCT);
  } catch (e) {
    defunct = true;
  }

  return defunct;
}

/**
* Load highlighter style sheet used for preventing transitions and
* applying transparency when calculating colour contrast.
*
* @param  {Window} win
*         Window where highlighting happens.
*/
function loadSheetForBackgroundCalculation(win) {
  loadSheet(win, HIGHLIGHTER_STYLES_SHEET);
}

/**
* Unload highlighter style sheet used for preventing transitions
* and applying transparency when calculating colour contrast.
*
* @param  {Window} win
*         Window where highlighting was happenning.
*/
function removeSheetForBackgroundCalculation(win) {
  removeSheet(win, HIGHLIGHTER_STYLES_SHEET);
}

/**
* Get role attribute for an accessible object if specified for its
* corresponding DOMNode.
*
* @param   {nsIAccessible} accessible
*          Accessible for which to determine its role attribute value.
*
* @returns {null|String}
*          Role attribute value if specified.
*/
function getAriaRoles(accessible) {
  try {
    return accessible.attributes.getStringProperty("xml-roles");
  } catch (e) {
    // No xml-roles. nsPersistentProperties throws if the attribute for a key
    // is not found.
  }

  return null;
}

exports.getAriaRoles = getAriaRoles;
exports.isDefunct = isDefunct;
exports.loadSheetForBackgroundCalculation = loadSheetForBackgroundCalculation;
exports.removeSheetForBackgroundCalculation =
  removeSheetForBackgroundCalculation;

quality100%

¤ Dauer der Verarbeitung: 0.14 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.