CINXE.COM
Understanding Success Criterion 3.2.2: On Input | WAI | W3C
<!DOCTYPE html><html lang="en" xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><head> <meta charset="UTF-8"> <title>Understanding Success Criterion 3.2.2: On Input | WAI | W3C</title> <meta name="viewport" content="width=device-width, initial-scale=1"> <link rel="stylesheet" href="https://w3.org/WAI/assets/css/style.css"> <link rel="stylesheet" href="base.css"> </head> <body dir="ltr"> <a href="#main" class="button button--skip-link">Skip to content</a> <div class="minimal-header-container default-grid"> <header class="minimal-header" id="site-header"> <div class="minimal-header-name"> <a href="https://www.w3.org/WAI/WCAG21/Understanding/">WCAG 2.1 Understanding Docs</a> </div> <div class="minimal-header-subtitle">Informative explanations, not required to meet WCAG</div> <a class="minimal-header-link" href="https://www.w3.org/WAI/WCAG21/Understanding/about">About WCAG Understanding Docs</a> <div class="minimal-header-logo"> <a href="http://w3.org/" aria-label="W3C"> <svg xmlns="http://www.w3.org/2000/svg" height="2em" viewBox="0 0 91.968 44"> <g fill-rule="evenodd" fill="none"> <path fill="#015a9c" d="M-.231-.21h92.917v44.659H-.23z"></path> <g fill-rule="nonzero" fill="#fff"> <path d="M21.752 0l7.789 26.78L37.329 0H58.444v2.662l-7.95 13.852c2.792.907 4.905 2.555 6.337 4.944 1.432 2.391 2.149 5.196 2.149 8.419 0 3.985-1.048 7.335-3.143 10.05C53.742 42.642 51.029 44 47.7 44c-2.507 0-4.691-.806-6.552-2.417-1.862-1.611-3.24-3.793-4.136-6.546l4.403-1.846c.646 1.666 1.496 2.979 2.552 3.938 1.056.96 2.3 1.438 3.733 1.438 1.504 0 2.775-.85 3.813-2.552 1.039-1.703 1.558-3.747 1.558-6.14 0-2.643-.556-4.69-1.664-6.138-1.29-1.701-3.314-2.554-6.071-2.554h-2.148v-2.606l7.52-13.147H41.63l-.516.889-11.04 37.678h-.536L21.48 16.73l-8.056 27.268h-.537L0 0h5.64l7.787 26.78 5.264-18.033L16.113 0zM87.958 0c-1.077 0-2.044.388-2.777 1.133-.777.79-1.21 1.81-1.21 2.866s.412 2.034 1.167 2.8C85.905 7.579 86.892 8 87.959 8c1.043 0 2.055-.422 2.843-1.188.755-.733 1.166-1.711 1.166-2.811a3.997 3.997 0 00-1.155-2.811A3.946 3.946 0 0087.958 0zm3.476 4.034a3.32 3.32 0 01-1.01 2.41c-.69.668-1.544 1.023-2.489 1.023a3.405 3.405 0 01-2.42-1.033c-.655-.667-1.022-1.523-1.022-2.433 0-.911.378-1.8 1.055-2.489.633-.645 1.488-.988 2.42-.988.955 0 1.81.356 2.477 1.033.645.643.99 1.51.99 2.477zm-3.366-2.378h-1.71v4.533h.855V4.256h.845l.922 1.933h.955l-1.012-2.066c.655-.134 1.033-.578 1.033-1.223 0-.822-.621-1.244-1.888-1.244zm-.155.555c.8 0 1.165.222 1.165.778 0 .533-.365.722-1.144.722h-.722v-1.5zM82.109 0l.862 5.914-3.05 6.588s-1.172-2.795-3.118-4.342c-1.64-1.303-2.708-1.586-4.378-1.198-2.145.5-4.577 3.394-5.638 6.963-1.27 4.27-1.283 6.336-1.328 8.234-.071 3.042.354 4.841.354 4.841s-1.853-3.868-1.835-9.533c.012-4.043.576-7.71 2.233-11.328 1.459-3.181 3.626-5.09 5.55-5.315 1.99-.232 3.562.85 4.777 2.02 1.276 1.23 2.565 3.918 2.565 3.918zM82.202 31.824s-1.338 2.567-2.171 3.556c-.834.99-2.326 2.732-4.167 3.603-1.842.872-2.808 1.036-4.628.849-1.82-.188-3.51-1.319-4.102-1.79-.592-.472-2.106-1.861-2.962-3.156C63.317 33.59 61.98 31 61.98 31s.745 2.596 1.212 3.698c.269.635 1.094 2.574 2.265 4.262 1.092 1.576 3.214 4.287 6.438 4.899 3.224.613 5.44-.942 5.987-1.319.549-.376 1.704-1.416 2.436-2.256.763-.877 1.486-1.995 1.886-2.666.292-.49.768-1.485.768-1.485z"></path> </g> </g> </svg> </a> <a href="http://w3.org/WAI/" aria-label="Web Accessibility Initiative"> <svg xmlns="http://www.w3.org/2000/svg" height="2em" viewBox="0 0 162.5 45.9"> <g fill="none" fill-rule="evenodd"> <path d="M0 0h162.5v45.9H0z" fill="#015a9c"></path> <path d="M1.2 24.5h160" stroke="#eed009" stroke-linecap="square" stroke-width="2"></path> <g fill="#fff" fill-rule="nonzero"> <path d="M15.741 15.5h-1.816L11.14 6.145c-.41-1.394-.65-2.334-.722-2.823-.104.749-.332 1.71-.684 2.881L7.04 15.5H5.223L1.444 1.223H3.32l2.217 8.72c.3 1.14.527 2.272.684 3.399.143-1.068.397-2.237.761-3.506l2.52-8.613h1.855l2.627 8.681c.339 1.127.6 2.272.781 3.438.105-.899.336-2.038.694-3.418l2.207-8.701h1.875zm10.127.195c-1.608 0-2.87-.486-3.784-1.46-.915-.973-1.372-2.312-1.372-4.018 0-1.719.426-3.088 1.279-4.107.853-1.019 2.005-1.528 3.457-1.528 1.348 0 2.422.435 3.223 1.304.8.869 1.2 2.046 1.2 3.53v1.064h-7.343c.033 1.218.342 2.142.928 2.774.586.631 1.416.947 2.49.947a8.46 8.46 0 001.631-.151c.514-.101 1.116-.298 1.807-.591v1.543a8.506 8.506 0 01-1.67.537c-.521.104-1.136.156-1.846.156zm-.44-9.677c-.84 0-1.503.27-1.992.81-.488.54-.778 1.292-.869 2.256h5.46c-.014-1.003-.245-1.764-.694-2.285-.45-.521-1.084-.781-1.904-.781zm12.237-1.416c1.413 0 2.503.486 3.271 1.46.769.973 1.153 2.332 1.153 4.077 0 1.77-.39 3.14-1.172 4.106-.781.967-1.865 1.45-3.252 1.45-.723 0-1.367-.13-1.934-.39a3.384 3.384 0 01-1.386-1.162h-.137a48.165 48.165 0 01-.362 1.357h-1.26V.305h1.759v3.691c0 .736-.033 1.471-.098 2.207h.098c.722-1.068 1.829-1.601 3.32-1.601zm-.293 1.455c-1.08 0-1.856.306-2.324.918-.47.612-.703 1.647-.703 3.105v.078c0 1.465.239 2.512.717 3.14.479.628 1.262.942 2.349.942.963 0 1.681-.353 2.153-1.06.472-.706.708-1.726.708-3.06 0-1.355-.237-2.37-.713-3.048-.475-.677-1.204-1.015-2.187-1.015zM59.286 15.5l-1.719-4.424h-5.664l-1.7 4.424h-1.816l5.577-14.336h1.62L61.152 15.5zM57.03 9.484L55.43 5.158l-.684-2.138c-.195.78-.4 1.494-.615 2.138l-1.621 4.326zm10.137 6.211c-1.543 0-2.744-.473-3.604-1.42-.86-.948-1.289-2.307-1.289-4.078 0-1.797.435-3.182 1.304-4.155.87-.973 2.108-1.46 3.716-1.46.52 0 1.037.054 1.548.161.51.108.932.246 1.264.415l-.537 1.465c-.905-.338-1.676-.508-2.314-.508-1.081 0-1.879.34-2.393 1.02-.514.681-.771 1.695-.771 3.043 0 1.295.257 2.287.771 2.973.514.687 1.276 1.03 2.285 1.03.944 0 1.872-.208 2.783-.624v1.562c-.742.384-1.663.576-2.763.576zm9.6 0c-1.544 0-2.745-.473-3.604-1.42-.86-.948-1.29-2.307-1.29-4.078 0-1.797.435-3.182 1.305-4.155.869-.973 2.107-1.46 3.715-1.46.521 0 1.037.054 1.548.161.511.108.933.246 1.265.415l-.537 1.465c-.905-.338-1.677-.508-2.315-.508-1.08 0-1.878.34-2.392 1.02-.515.681-.772 1.695-.772 3.043 0 1.295.257 2.287.772 2.973.514.687 1.276 1.03 2.285 1.03.944 0 1.872-.208 2.783-.624v1.562c-.742.384-1.663.576-2.764.576zm9.863 0c-1.608 0-2.87-.486-3.784-1.46-.915-.973-1.373-2.312-1.373-4.018 0-1.719.427-3.088 1.28-4.107.853-1.019 2.005-1.528 3.457-1.528 1.347 0 2.422.435 3.222 1.304.801.869 1.202 2.046 1.202 3.53v1.064H83.29c.032 1.218.342 2.142.928 2.774.586.631 1.416.947 2.49.947a8.46 8.46 0 001.63-.151c.515-.101 1.117-.298 1.807-.591v1.543a8.506 8.506 0 01-1.67.537c-.52.104-1.136.156-1.845.156zm-.44-9.677c-.84 0-1.504.27-1.992.81s-.778 1.292-.87 2.256h5.46c-.013-1.003-.244-1.764-.693-2.285-.45-.521-1.084-.781-1.905-.781zm14.14 6.523c0 1.003-.373 1.779-1.122 2.33-.749.55-1.8.824-3.154.824-1.413 0-2.536-.224-3.37-.674V13.42c1.179.573 2.315.86 3.409.86.885 0 1.53-.144 1.933-.43.404-.287.606-.671.606-1.153 0-.423-.194-.781-.581-1.074-.388-.293-1.076-.628-2.066-1.006-1.009-.39-1.719-.724-2.129-1-.41-.277-.711-.588-.903-.933-.192-.345-.288-.765-.288-1.26 0-.88.358-1.572 1.074-2.08.716-.508 1.7-.762 2.95-.762a8.17 8.17 0 013.417.723L99.511 6.7c-1.088-.456-2.068-.683-2.94-.683-.73 0-1.282.115-1.66.346-.378.231-.566.549-.566.952 0 .391.162.715.488.972.325.257 1.084.614 2.275 1.07.892.331 1.551.64 1.978.927.426.287.74.609.942.967.202.358.303.788.303 1.289zm9.58 0c0 1.003-.373 1.779-1.122 2.33-.749.55-1.8.824-3.154.824-1.413 0-2.536-.224-3.37-.674V13.42c1.179.573 2.315.86 3.409.86.885 0 1.53-.144 1.933-.43.404-.287.606-.671.606-1.153 0-.423-.194-.781-.581-1.074-.388-.293-1.076-.628-2.066-1.006-1.009-.39-1.719-.724-2.129-1-.41-.277-.71-.588-.903-.933-.192-.345-.288-.765-.288-1.26 0-.88.358-1.572 1.074-2.08.716-.508 1.7-.762 2.95-.762a8.17 8.17 0 013.417.723l-.595 1.396c-1.088-.456-2.067-.683-2.94-.683-.729 0-1.282.115-1.66.346-.378.231-.566.549-.566.952 0 .391.162.715.488.972.325.257 1.084.614 2.275 1.07.892.331 1.551.64 1.978.927.426.287.74.609.942.967.202.358.303.788.303 1.289zm4.356 2.959h-1.757V4.777h1.757zm-1.894-13.623c0-.39.1-.674.298-.85.198-.175.444-.263.737-.263.273 0 .513.088.718.263.205.176.307.46.307.85 0 .384-.102.667-.307.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.199-.183-.298-.466-.298-.85zm10.371 2.725c1.413 0 2.503.486 3.271 1.46.769.973 1.153 2.332 1.153 4.077 0 1.77-.39 3.14-1.172 4.106-.781.967-1.865 1.45-3.252 1.45-.723 0-1.367-.13-1.934-.39a3.384 3.384 0 01-1.386-1.162h-.137a48.244 48.244 0 01-.361 1.357h-1.26V.305h1.758v3.691c0 .736-.033 1.471-.098 2.207h.098c.722-1.068 1.83-1.601 3.32-1.601zm-.293 1.455c-1.08 0-1.855.306-2.324.918-.469.612-.703 1.647-.703 3.105v.078c0 1.465.239 2.512.717 3.14.479.628 1.262.942 2.35.942.963 0 1.68-.353 2.152-1.06.472-.706.708-1.726.708-3.06 0-1.355-.237-2.37-.713-3.048-.475-.677-1.204-1.015-2.187-1.015zm9.277 9.443h-1.757V4.777h1.757zm-1.894-13.623c0-.39.1-.674.298-.85.198-.175.444-.263.737-.263.273 0 .513.088.718.263.205.176.307.46.307.85 0 .384-.102.667-.307.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.199-.183-.298-.466-.298-.85zm7.05 13.623h-1.757V.305h1.758zm5.157 0h-1.758V4.777h1.758zm-1.895-13.623c0-.39.1-.674.298-.85.199-.175.444-.263.737-.263.274 0 .513.088.718.263.205.176.308.46.308.85 0 .384-.103.667-.308.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.198-.183-.298-.466-.298-.85zm8.877 12.383c.228 0 .495-.023.801-.069.306-.045.537-.097.693-.156v1.348c-.162.071-.415.141-.756.21a5.29 5.29 0 01-1.04.102c-2.097 0-3.145-1.103-3.145-3.31v-6.24h-1.514v-.84l1.534-.703.703-2.286h1.045v2.461h3.095v1.368h-3.095v6.19c0 .62.148 1.095.444 1.427.296.332.708.498 1.235.498zm1.953-9.483h1.885l2.315 6.104c.488 1.328.787 2.301.898 2.92h.078c.059-.241.192-.692.4-1.353.209-.66.385-1.19.528-1.587l2.178-6.084h1.894l-4.619 12.207c-.45 1.185-.983 2.035-1.602 2.55-.618.514-1.383.77-2.294.77-.489 0-.974-.055-1.456-.165v-1.397c.326.078.717.117 1.172.117.56 0 1.035-.154 1.426-.463.39-.31.71-.787.957-1.431l.557-1.426zM7.157 45.5H2.001v-1.035l1.68-.381V32.658l-1.68-.4v-1.035h5.156v1.035l-1.68.4v11.426l1.68.38zm9.824 0v-6.855c0-.873-.193-1.522-.58-1.949-.388-.426-.995-.64-1.822-.64-1.1 0-1.9.305-2.398.914-.498.608-.747 1.6-.747 2.973V45.5H9.677V34.777h1.416l.263 1.465h.098a3.31 3.31 0 011.396-1.225 4.492 4.492 0 011.983-.435c1.315 0 2.292.319 2.93.957.638.638.957 1.63.957 2.979V45.5zm6.817 0H22.04V34.777h1.758zm-1.895-13.623c0-.39.1-.674.298-.85.199-.175.444-.263.737-.263.274 0 .513.088.718.263.205.176.308.46.308.85 0 .384-.103.667-.308.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.199-.183-.298-.466-.298-.85zM30.78 44.26c.228 0 .495-.023.8-.069.307-.045.538-.097.694-.156v1.348c-.163.071-.415.141-.757.21a5.29 5.29 0 01-1.04.102c-2.096 0-3.144-1.103-3.144-3.31v-6.24h-1.514v-.84l1.533-.703.703-2.286H29.1v2.461h3.096v1.368H29.1v6.19c0 .62.149 1.095.445 1.427.296.332.708.498 1.235.498zm5.39 1.24h-1.757V34.777h1.758zm-1.894-13.623c0-.39.1-.674.298-.85.199-.175.444-.263.737-.263.274 0 .513.088.718.263.205.176.308.46.308.85 0 .384-.103.667-.308.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.199-.183-.298-.466-.298-.85zM46.19 45.5l-.342-1.523h-.078c-.534.67-1.066 1.124-1.596 1.362-.53.237-1.2.356-2.007.356-1.055 0-1.882-.276-2.48-.83-.6-.553-.9-1.334-.9-2.344 0-2.174 1.716-3.313 5.147-3.417l1.817-.069V38.4c0-.813-.176-1.414-.528-1.801-.351-.388-.914-.581-1.689-.581-.566 0-1.102.084-1.606.253-.505.17-.979.359-1.421.567l-.537-1.318a7.958 7.958 0 011.767-.674 7.642 7.642 0 011.895-.244c1.295 0 2.259.286 2.89.859.632.573.948 1.484.948 2.734V45.5zm-3.623-1.22c.983 0 1.756-.266 2.32-.797.563-.53.844-1.284.844-2.26v-.967l-1.582.068c-1.23.046-2.127.241-2.69.586-.563.345-.845.889-.845 1.631 0 .56.171.99.513 1.29.342.299.822.448 1.44.448zm11.807-.02c.228 0 .495-.023.8-.069.307-.045.538-.097.694-.156v1.348c-.163.071-.415.141-.757.21a5.29 5.29 0 01-1.04.102c-2.096 0-3.144-1.103-3.144-3.31v-6.24h-1.514v-.84l1.533-.703.703-2.286h1.045v2.461h3.096v1.368h-3.096v6.19c0 .62.148 1.095.444 1.427.297.332.708.498 1.236.498zm5.39 1.24h-1.757V34.777h1.757zM57.87 31.877c0-.39.1-.674.298-.85.198-.175.444-.263.737-.263.274 0 .513.088.718.263.205.176.307.46.307.85 0 .384-.102.667-.307.85a1.047 1.047 0 01-.718.273 1.05 1.05 0 01-.737-.273c-.199-.183-.298-.466-.298-.85zM65.526 45.5l-4.062-10.723h1.884l2.276 6.319c.45 1.27.736 2.216.86 2.842h.077a11.495 11.495 0 01.176-.64c.04-.127.28-.861.723-2.202l2.285-6.319h1.875L67.548 45.5zm12.354.195c-1.608 0-2.87-.486-3.784-1.46-.915-.973-1.373-2.312-1.373-4.018 0-1.719.427-3.088 1.28-4.107.853-1.019 2.005-1.528 3.457-1.528 1.347 0 2.422.435 3.222 1.304.801.869 1.202 2.046 1.202 3.53v1.064H74.54c.032 1.218.342 2.142.928 2.774.586.631 1.416.947 2.49.947a8.46 8.46 0 001.63-.151c.515-.101 1.117-.298 1.807-.591v1.543a8.506 8.506 0 01-1.67.537c-.52.104-1.136.156-1.845.156zm-.44-9.677c-.84 0-1.504.27-1.992.81s-.778 1.292-.87 2.256h5.46c-.013-1.003-.244-1.764-.693-2.285-.45-.521-1.084-.781-1.905-.781zM137.741 45.5h-1.816l-2.784-9.355c-.41-1.394-.65-2.334-.722-2.823-.104.749-.332 1.71-.684 2.881L129.04 45.5h-1.817l-3.779-14.277h1.875l2.217 8.72c.3 1.14.527 2.272.684 3.399.143-1.068.397-2.237.761-3.506l2.52-8.613h1.855l2.627 8.681c.339 1.127.6 2.272.781 3.438.105-.899.336-2.038.694-3.418l2.207-8.701h1.875zm14.57 0l-1.718-4.424h-5.664l-1.7 4.424h-1.816l5.576-14.336h1.621l5.567 14.336zm-2.256-6.016l-1.601-4.326-.684-2.138c-.195.78-.4 1.494-.615 2.138l-1.621 4.326zm10.098 6.016h-5.156v-1.035l1.68-.381V32.658l-1.68-.4v-1.035h5.156v1.035l-1.68.4v11.426l1.68.38z"></path> </g> </g> </svg> </a> </div> </header> </div> <div class="default-grid nav-container nav-page-specific"> <div class="nav"> <nav class="nav standalone-resource-pager" aria-label="Understanding Docs"> <ul> <li class="nav__item"> <a href=".">All Understanding Docs</a> </li> <li class="nav__item"> <a href="predictable"> <svg alt="up" focusable="false" aria-hidden="true" class="icon-arrow-up-thin pager-icon" viewBox="0 0 16 16"> <path fill-rule="evenodd" d="M8 12a.5.5 0 0 0 .5-.5V5.707l2.146 2.147a.5.5 0 0 0 .708-.708l-3-3a.5.5 0 0 0-.708 0l-3 3a.5.5 0 1 0 .708.708L7.5 5.707V11.5a.5.5 0 0 0 .5.5z"></path> </svg> Guideline: Predictable </a> </li> <li class="nav__item"> <a href="on-focus"> <svg focusable="false" aria-hidden="true" class="icon-arrow-left-thin pager-icon" viewBox="0 0 16 16"> <path fill-rule="evenodd" d="M12 8a.5.5 0 0 1-.5.5H5.707l2.147 2.146a.5.5 0 0 1-.708.708l-3-3a.5.5 0 0 1 0-.708l3-3a.5.5 0 1 1 .708.708L5.707 7.5H11.5a.5.5 0 0 1 .5.5z"></path> </svg> Previous SC: On Focus </a> </li> <li class="nav__item"> <a href="consistent-navigation"> Next SC: Consistent Navigation <svg focusable="false" aria-hidden="true" class="icon-arrow-right-thin pager-icon" viewBox="0 0 16 16"> <path fill-rule="evenodd" d="M4 8a.5.5 0 0 1 .5-.5h5.793L8.146 5.354a.5.5 0 1 1 .708-.708l3 3a.5.5 0 0 1 0 .708l-3 3a.5.5 0 0 1-.708-.708L10.293 8.5H4.5A.5.5 0 0 1 4 8z"></path> </svg> </a> </li> </ul> </nav> </div> </div> <div class="default-grid with-gap leftcol"> <aside class="box nav-hack sidebar standalone-resource__sidebar"> <header class="box-h">Page Contents</header> <div class="box-i"> <nav aria-label="page contents" class="navtoc"> <ul><li><a href="#brief">In Brief</a></li> <li><a href="#success-criterion">Success Criterion</a></li> <li><a href="#intent">Intent</a></li> <li><a href="#benefits">Benefits</a></li> <li><a href="#examples">Examples</a></li> <li><a href="#techniques">Techniques</a></li> <li><a href="#key-terms">Key Terms</a></li> </ul> </nav> </div> </aside> <main id="main" class="standalone-resource__main"> <h1> <span class="standalone-resource__type-of-guidance"> Understanding <a href="https://w3.org/TR/WCAG21#on-input">SC 3.2.2</a>: </span>On Input (Level A) </h1> <section id="brief"> <h2>In Brief</h2> <dl> <dt>Goal</dt><dd>Content can be operated more predictably.</dd> <dt>What to do</dt><dd>Forewarn users if their context will change based on their input.</dd> <dt>Why it's important</dt><dd>Content that behaves predictably is especially important to people with disabilities.</dd> </dl> </section> <section id="success-criterion" class="box"> <h2 class="box-h box-h-icon">Success Criterion (SC)</h2> <div class="box-i"><p>Changing the setting of any <a href="#dfn-user-interface-component">user interface component</a> does not automatically cause a <a href="#dfn-changes-of-context">change of context</a> unless the user has been advised of the behavior before using the component. </p></div> </section> <section id="intent"> <h2>Intent</h2> <p>The intent of this Success Criterion is to ensure that entering data or selecting a form control has predictable effects. Changing the setting of any user interface component is changing some aspect in the control that will persist when the user is no longer interacting with it. So checking a checkbox, entering text into a text field, or changing the selected option in a list control changes its setting, but activating a link or a button does not. Changes in context can confuse users who do not easily perceive the change or are easily distracted by changes. Changes of context are appropriate only when it is clear that such a change will happen in response to the user's action. </p> <div class="note"> <p class="note-title marker">Note</p> <div> <p>This Success Criterion covers changes in context due to changing the setting of a control. Clicking on links or buttons is activating a control, not changing the setting of that control. </p> </div> </div> <div class="note"> <p class="note-title marker">Note</p> <div> <p>What is meant by "component" and "user interface component" here is also sometimes called "user interface element". </p> </div> </div> </section> <section id="benefits"> <h2>Benefits</h2> <ul> <li>This Success Criterion helps users with disabilities by making interactive content more predictable. Unexpected changes of context can be so disorienting for users with visual disabilities or cognitive limitations that they are unable to use the content. </li> <li> <p>Individuals who are unable to detect changes of context are less likely to become disoriented while navigating a site. For example: </p> <ul> <li>Individuals who are blind or have low vision may have difficulty knowing when a visual context change has occurred, such as a new window popping up. In this case, warning users of context changes in advance minimizes confusion when the user discovers that the back button no longer behaves as expected. </li> </ul> </li> <li>Some individuals with low vision, with reading and intellectual disabilities, and others who have difficulty interpreting visual cues may benefit from additional cues in order to detect changes of context. </li> </ul> </section> <section id="examples"> <h2>Examples</h2> <ul> <li> A form is provided for creating calendar entries in a Web based calendaring and scheduling application. Along with the standard fields for subject, time and location, there is a set of radio buttons to select the type of calendar entry to create. The calendar entry type can be meeting, appointment or reminder. If the user selects the radio for meeting, additional fields are displayed on the page for entering the meeting participants. Different fields appear if the reminder button is chosen. Because only parts of the entry change and the overall structure remains the same the basic context remains for the user. </li> <li> A form contains fields representing US phone numbers. All of the numbers have a three digit area code followed by a three digit prefix and finally a four digit number, and each part of the phone number is entered into a separate field. When the user completes the entry of one field the focus automatically moves to the next field of the phone number. This behavior of phone fields is described for the user at the beginning of the form. </li> </ul> </section> <section id="techniques"> <h2>Techniques</h2> <p> Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see <a href="understanding-techniques">Understanding Techniques for WCAG Success Criteria</a>, particularly the "Other Techniques" section. </p> <section id="sufficient"> <h3>Sufficient Techniques</h3> <ul> <li> <p> <a href="https://www.w3.org/WAI/WCAG21/Techniques/general/G80">G80: Providing a submit button to initiate a change of context</a> using a technology-specific technique listed below </p> <ul> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/html/H32">H32: Providing submit buttons</a> </li> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/html/H84">H84: Using a button with a select element to perform an action</a> </li> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/pdf/PDF15">PDF15: Providing submit buttons with the submit-form action in PDF forms</a> </li> </ul> </li> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/general/G13">G13: Describing what will happen before a change to a form control that causes a change of context to occur is made</a> </li> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/client-side-script/SCR19">SCR19: Using an onchange event on a select element without causing a change of context</a> </li> </ul> <div class="note"> <p class="note-title marker">Note</p> <div> <p>A change of content is not always a <a class="glossary" href="#dfn-changes-of-context">change of context</a>. This success criterion is automatically met if changes in content are not also changes of context. </p> </div> </div> </section> <section id="advisory"> <h3>Advisory Techniques</h3> <p> Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations. </p> <ul> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/general/G201">G201: Giving users advanced warning when opening a new window</a> </li> </ul> </section> <section id="failure"> <h3>Failures</h3> <p> The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group. </p> <ul> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/failures/F36">F36: Failure of Success Criterion 3.2.2 due to automatically submitting a form and … given a value</a> </li> <li> <a href="https://www.w3.org/WAI/WCAG21/Techniques/failures/F37">F37: Failure of Success Criterion 3.2.2 due to launching a new window without prior warning when the selection of a radio button, check box or select list is changed</a> </li> </ul> </section> </section> <section id="key-terms"> <details> <summary><h2>Key Terms</h2></summary> <dl><dt id="dfn-assistive-technology">assistive technology</dt><dd><definition><p>hardware and/or software that acts as a <a href="#dfn-user-agent">user agent</a>, or along with a mainstream user agent, to provide functionality to meet the requirements of users with disabilities that go beyond those offered by mainstream user agents </p> <div class="note"> <p class="note-title marker">Note</p> <p>functionality provided by assistive technology includes alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible). </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>Assistive technologies often communicate data and messages with mainstream user agents by using and monitoring APIs. </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>The distinction between mainstream user agents and assistive technologies is not absolute. Many mainstream user agents provide some features to assist individuals with disabilities. The basic difference is that mainstream user agents target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The mainstream user agent may provide important functionality to assistive technologies like retrieving Web content from program objects or parsing markup into identifiable bundles. </p> </div> <aside class="example"><p class="example-title marker">Example</p><p>Assistive technologies that are important in the context of this document include the following: </p></aside> <ul> <li>screen magnifiers, and other visual reading assistants, which are used by people with visual, perceptual and physical print disabilities to change text font, size, spacing, color, synchronization with speech, etc. in order to improve the visual readability of rendered text and images; </li> <li>screen readers, which are used by people who are blind to read textual information through synthesized speech or braille; </li> <li>text-to-speech software, which is used by some people with cognitive, language, and learning disabilities to convert text into synthetic speech; </li> <li>speech recognition software, which may be used by people who have some physical disabilities;</li> <li>alternative keyboards, which are used by people with certain physical disabilities to simulate the keyboard (including alternate keyboards that use head pointers, single switches, sip/puff and other special input devices.); </li> <li>alternative pointing devices, which are used by people with certain physical disabilities to simulate mouse pointing and button activations. </li> </ul></definition></dd><dt id="dfn-changes-of-context">changes of context</dt><dd><definition><p>major changes that, if made without user awareness, can disorient users who are not able to view the entire page simultaneously </p> <p>Changes in context include changes of:</p> <ol> <li><a href="#dfn-user-agent">user agent</a>; </li> <li><a href="#dfn-viewport">viewport</a>; </li> <li>focus;</li> <li><a href="#dfn-content">content</a> that changes the meaning of the <a href="#dfn-web-page">Web page</a> </li> </ol> <div class="note"> <p class="note-title marker">Note</p> <p>A change of content is not always a change of context. Changes in content, such as an expanding outline, dynamic menu, or a tab control do not necessarily change the context, unless they also change one of the above (e.g., focus). </p> </div> <aside class="example"><p class="example-title marker">Example</p><p>Opening a new window, moving focus to a different component, going to a new page (including anything that would look to a user as if they had moved to a new page) or significantly re-arranging the content of a page are examples of changes of context. </p></aside></definition></dd><dt id="dfn-content">content</dt><dd><definition><p>information and sensory experience to be communicated to the user by means of a <a href="#dfn-user-agent">user agent</a>, including code or markup that defines the content's <a href="#dfn-structure">structure</a>, <a href="#dfn-presentation">presentation</a>, and interactions </p></definition></dd><dt id="dfn-presentation">presentation</dt><dd><definition><p>rendering of the <a href="#dfn-content">content</a> in a form to be perceived by users </p></definition></dd><dt id="dfn-structure">structure</dt><dd><definition><ol> <li>The way the parts of a <a href="#dfn-web-page">Web page</a> are organized in relation to each other; and </li> <li>The way a collection of <a href="#dfn-web-page">Web pages</a> is organized </li> </ol></definition></dd><dt id="dfn-user-agent">user agent</dt><dd><definition><p>any software that retrieves and presents Web content for users</p> <aside class="example"><p class="example-title marker">Example</p><p>Web browsers, media players, plug-ins, and other programs — including <a href="#dfn-assistive-technology">assistive technologies</a> — that help in retrieving, rendering, and interacting with Web content. </p></aside></definition></dd><dt id="dfn-user-interface-component">user interface component</dt><dd><definition><p>a part of the content that is perceived by users as a single control for a distinct function </p> <div class="note"> <p class="note-title marker">Note</p> <p>Multiple user interface components may be implemented as a single programmatic element. "Components" here is not tied to programming techniques, but rather to what the user perceives as separate controls. </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>User interface components include form elements and links as well as components generated by scripts. </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>What is meant by "component" or "user interface component" here is also sometimes called "user interface element". </p> </div> <aside class="example"><p class="example-title marker">Example</p><p>An applet has a "control" that can be used to move through content by line or page or random access. Since each of these would need to have a name and be settable independently, they would each be a "user interface component." </p></aside></definition></dd><dt id="dfn-viewport">viewport</dt><dd><definition><p>object in which the user agent presents content</p> <div class="note"> <p class="note-title marker">Note</p> <p>The <a href="#dfn-user-agent">user agent</a> presents content through one or more viewports. Viewports include windows, frames, loudspeakers, and virtual magnifying glasses. A viewport may contain another viewport (e.g., nested frames). Interface components created by the user agent such as prompts, menus, and alerts are not viewports. </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>This definition is based on <a href="https://www.w3.org/TR/WAI-USERAGENT/glossary.html">User Agent Accessibility Guidelines 1.0 Glossary</a> [<a href="https://www.w3.org/TR/UAAG10/">UAAG10</a>]. </p> </div></definition></dd><dt id="dfn-web-page">Web page</dt><dd><definition><p>a non-embedded resource obtained from a single URI using HTTP plus any other resources that are used in the rendering or intended to be rendered together with it by a <a href="#dfn-user-agent">user agent</a></p> <div class="note"> <p class="note-title marker">Note</p> <p>Although any "other resources" would be rendered together with the primary resource, they would not necessarily be rendered simultaneously with each other. </p> </div> <div class="note"> <p class="note-title marker">Note</p> <p>For the purposes of conformance with these guidelines, a resource must be "non-embedded" within the scope of conformance to be considered a Web page. </p> </div> <aside class="example"><p class="example-title marker">Example</p><p>A Web resource including all embedded images and media.</p></aside> <aside class="example"><p class="example-title marker">Example</p><p>A Web mail program built using Asynchronous JavaScript and XML (AJAX). The program lives entirely at http://example.com/mail, but includes an inbox, a contacts area and a calendar. Links or buttons are provided that cause the inbox, contacts, or calendar to display, but do not change the URI of the page as a whole. </p></aside> <aside class="example"><p class="example-title marker">Example</p><p>A customizable portal site, where users can choose content to display from a set of different content modules. </p></aside> <aside class="example"><p class="example-title marker">Example</p><p>When you enter "http://shopping.example.com/" in your browser, you enter a movie-like interactive shopping environment where you visually move around in a store dragging products off of the shelves around you and into a visual shopping cart in front of you. Clicking on a product causes it to be demonstrated with a specification sheet floating alongside. This might be a single-page Web site or just one page within a Web site. </p></aside></definition></dd></dl> </details> </section> <a class="button button-backtotop" href="#top"> <span> <svg focusable="false" aria-hidden="true" class="icon-arrow-up " viewBox="0 0 26 28"> <path d="M25.172 15.172c0 0.531-0.219 1.031-0.578 1.406l-1.172 1.172c-0.375 0.375-0.891 0.594-1.422 0.594s-1.047-0.219-1.406-0.594l-4.594-4.578v11c0 1.125-0.938 1.828-2 1.828h-2c-1.062 0-2-0.703-2-1.828v-11l-4.594 4.578c-0.359 0.375-0.875 0.594-1.406 0.594s-1.047-0.219-1.406-0.594l-1.172-1.172c-0.375-0.375-0.594-0.875-0.594-1.406s0.219-1.047 0.594-1.422l10.172-10.172c0.359-0.375 0.875-0.578 1.406-0.578s1.047 0.203 1.422 0.578l10.172 10.172c0.359 0.375 0.578 0.891 0.578 1.422z"></path> </svg> Back to Top </span> </a> </main> <aside class="box box-icon box-space-above" id="helpimprove" style="grid-column: 2 / 8; grid-row: 3"> <header class="box-h box-h-icon box-h-space-above box-h-icon"> <svg focusable="false" aria-hidden="true" class="icon-comments" viewBox="0 0 28 28"> <path d="M22 12c0 4.422-4.922 8-11 8-0.953 0-1.875-0.094-2.75-0.25-1.297 0.922-2.766 1.594-4.344 2-0.422 0.109-0.875 0.187-1.344 0.25h-0.047c-0.234 0-0.453-0.187-0.5-0.453v0c-0.063-0.297 0.141-0.484 0.313-0.688 0.609-0.688 1.297-1.297 1.828-2.594-2.531-1.469-4.156-3.734-4.156-6.266 0-4.422 4.922-8 11-8s11 3.578 11 8zM28 16c0 2.547-1.625 4.797-4.156 6.266 0.531 1.297 1.219 1.906 1.828 2.594 0.172 0.203 0.375 0.391 0.313 0.688v0c-0.063 0.281-0.297 0.484-0.547 0.453-0.469-0.063-0.922-0.141-1.344-0.25-1.578-0.406-3.047-1.078-4.344-2-0.875 0.156-1.797 0.25-2.75 0.25-2.828 0-5.422-0.781-7.375-2.063 0.453 0.031 0.922 0.063 1.375 0.063 3.359 0 6.531-0.969 8.953-2.719 2.609-1.906 4.047-4.484 4.047-7.281 0-0.812-0.125-1.609-0.359-2.375 2.641 1.453 4.359 3.766 4.359 6.375z"></path> </svg> <h2>Help improve this page</h2> </header> <div class="box-i"> <p>Please share your ideas, suggestions, or comments via e-mail to the publicly-archived list <a href="mailto:public-agwg-comments@w3.org?subject=%5BUnderstanding%20and%20Techniques%20Feedback%5D">public-agwg-comments@w3.org</a> or via GitHub</p> <div class="button-group"> <a href="mailto:public-agwg-comments@w3.org?subject=%5BUnderstanding%20and%20Techniques%20Feedback%5D" class="button"><span>E-mail</span></a> <a href="https://github.com/w3c/wcag/issues/" class="button"><span>Fork & Edit on GitHub</span></a> <a href="https://github.com/w3c/wcag/issues/new" class="button"><span>New GitHub Issue</span></a> </div> </div> </aside> </div> <footer id="wai-site-footer" class="page-footer default-grid" aria-label="Page"> <div class="inner" style="grid-column: 2 / 8"> <p><strong>Date:</strong> Updated 29 July 2024.</p> <p><strong>Developed by</strong> <a href="https://www.w3.org/groups/wg/ag/participants">Accessibility Guidelines Working Group (AG WG) Participants</a> (Co-Chairs: Alastair Campbell, Charles Adams, Rachael Bradley Montgomery. W3C Staff Contact: Michael Cooper). </p> <p>The content was developed as part of the <a href="https://www.w3.org/WAI/about/projects/#us">WAI-Core projects</a> funded by U.S. Federal funds. The user interface was designed by the Education and Outreach Working Group (<a href="https://www.w3.org/groups/wg/eowg/participants">EOWG</a>) with contributions from Shadi Abou-Zahra, Steve Lee, and Shawn Lawton Henry as part of the <a href="https://www.w3.org/WAI/about/projects/wai-guide/">WAI-Guide</a> project, co-funded by the European Commission. </p> </div> </footer> <footer class="site-footer grid-4q" aria-label="Site"> <div class="q1-start q3-end about"> <div> <p><a class="largelink" href="https://www.w3.org/WAI/" dir="auto" translate="no" lang="en">W3C Web Accessibility Initiative (WAI)</a></p> <p>Strategies, standards, and supporting resources to make the Web accessible to people with disabilities.</p> </div> <div class="social" dir="auto" translate="no" lang="en"> <ul> <li><a href="https://twitter.com/w3c_wai"><svg focusable="false" aria-hidden="true" class="icon-twitter " viewBox="0 0 32 32"><path d="M31.939 6.092c-1.18 0.519-2.44 0.872-3.767 1.033 1.352-0.815 2.392-2.099 2.884-3.631-1.268 0.74-2.673 1.279-4.169 1.579-1.195-1.279-2.897-2.079-4.788-2.079-3.623 0-6.56 2.937-6.56 6.556 0 0.52 0.060 1.020 0.169 1.499-5.453-0.257-10.287-2.876-13.521-6.835-0.569 0.963-0.888 2.081-0.888 3.3 0 2.28 1.16 4.284 2.917 5.461-1.076-0.035-2.088-0.331-2.971-0.821v0.081c0 3.18 2.257 5.832 5.261 6.436-0.551 0.148-1.132 0.228-1.728 0.228-0.419 0-0.82-0.040-1.221-0.115 0.841 2.604 3.26 4.503 6.139 4.556-2.24 1.759-5.079 2.807-8.136 2.807-0.52 0-1.039-0.031-1.56-0.089 2.919 1.859 6.357 2.945 10.076 2.945 12.072 0 18.665-9.995 18.665-18.648 0-0.279 0-0.56-0.020-0.84 1.281-0.919 2.4-2.080 3.28-3.397l-0.063-0.027z"></path></svg> Twitter</a></li> <li><a href="https://www.w3.org/WAI/feed.xml"><svg focusable="false" aria-hidden="true" class="icon-rss " viewBox="0 0 32 32"><path d="M25.599 32c0-14.044-11.555-25.6-25.599-25.6v-6.4c17.553 0 32 14.447 32 32h-6.401zM4.388 23.22c2.419 0 4.391 1.972 4.391 4.393 0 2.417-1.98 4.387-4.401 4.387-2.417 0-4.377-1.965-4.377-4.387s1.967-4.392 4.388-4.393zM21.212 32h-6.22c0-8.225-6.767-14.993-14.992-14.993v-6.22c11.636 0 21.212 9.579 21.212 21.213z"></path></svg> Feed</a></li> <li><a href="https://www.youtube.com/channel/UCU6ljj3m1fglIPjSjs2DpRA/playlistsv"><svg focusable="false" aria-hidden="true" class="icon-youtube " viewBox="0 0 32 32"><path d="M31.327 8.273c-0.386-1.353-1.431-2.398-2.756-2.777l-0.028-0.007c-2.493-0.668-12.528-0.668-12.528-0.668s-10.009-0.013-12.528 0.668c-1.353 0.386-2.398 1.431-2.777 2.756l-0.007 0.028c-0.443 2.281-0.696 4.903-0.696 7.585 0 0.054 0 0.109 0 0.163l-0-0.008c-0 0.037-0 0.082-0 0.126 0 2.682 0.253 5.304 0.737 7.845l-0.041-0.26c0.386 1.353 1.431 2.398 2.756 2.777l0.028 0.007c2.491 0.669 12.528 0.669 12.528 0.669s10.008 0 12.528-0.669c1.353-0.386 2.398-1.431 2.777-2.756l0.007-0.028c0.425-2.233 0.668-4.803 0.668-7.429 0-0.099-0-0.198-0.001-0.297l0 0.015c0.001-0.092 0.001-0.201 0.001-0.31 0-2.626-0.243-5.196-0.708-7.687l0.040 0.258zM12.812 20.801v-9.591l8.352 4.803z"></path></svg> YouTube</a></li> <li><a href="https://www.w3.org/WAI/news/subscribe/" class="button">Get News in Email</a></li> </ul> </div> <div dir="auto" translate="no" lang="en"> <p>Copyright © 2024 World Wide Web Consortium (<a href="https://www.w3.org/">W3C</a><sup>®</sup>). See <a href="/WAI/about/using-wai-material/">Permission to Use WAI Material</a>.</p> </div> </div> <div dir="auto" translate="no" class="q4-start q4-end" lang="en"> <ul style="margin-bottom:0"> <li><a href="/WAI/about/contacting/">Contact WAI</a></li> <li><a href="/WAI/sitemap/">Site Map</a></li> <li><a href="/WAI/news/">News</a></li> <li><a href="/WAI/about/accessibility-statement/">Accessibility Statement</a></li> <li><a href="/WAI/translations/"> Translations</a></li> <li><a href="/WAI/roles/">Resources for Roles</a></li> </ul> </div> </footer> <link rel="stylesheet" href="../a11y-light.css"> <script src="../highlight.min.js"></script> <script> hljs.configure({ cssSelector: 'pre' }); hljs.highlightAll(); var translationStrings = {}; /* fix WAI JS */ </script> <script src="https://www.w3.org/WAI/assets/scripts/main.js"></script> <script> var _paq = _paq || []; /* tracker methods like "setCustomDimension" should be called before "trackPageView" */ _paq.push(["setDoNotTrack", true]); _paq.push(['trackPageView']); _paq.push(['enableLinkTracking']); (function () { var u = "//www.w3.org/analytics/piwik/"; _paq.push(['setTrackerUrl', u + 'piwik.php']); _paq.push(['setSiteId', '328']); var d = document, g = d.createElement('script'), s = d.getElementsByTagName('script')[0]; g.type = 'text/javascript'; g.async = true; g.defer = true; g.src = u + 'piwik.js'; s.parentNode.insertBefore(g, s); })(); </script> <noscript> <p><img src="//www.w3.org/analytics/piwik/piwik.php?idsite=328&rec=1" style="border:0;" alt="" /></p> </noscript> </body></html>