before-after-slider前后对比滑杆
Before / after slider英文定义
A draggable boundary changes the visible share of two aligned layers for direct comparison.
中文翻译
通过可拖动分割线在两张叠放图片之间擦拭切换,以便对比。
before-after-slider用可拖动分割线比较同一画面的前后状态。
通过可拖动分割线在两张叠放图片之间擦拭切换,以便对比。
实现「前后对比滑杆」:用可拖动分割线比较同一画面的前后状态。 参数设为分割位置 50%、时长 180ms。由真实的指针、触摸或键盘交互触发。使用语义化 HTML,CSS 作用域限定在 .motion-demo--before-after-slider,并挂载随组件提供的原生 JavaScript 交互运行时。为 prefers-reduced-motion 和 .force-reduced-motion 提供等价的低动态方案。
<div class="motion-demo motion-demo--before-after-slider" data-motion="before-after-slider" aria-label="前后对比滑杆 示例">
<figure class="motion-comparison" data-comparison><div class="motion-before">调整前</div><div class="motion-after" data-comparison-after>调整后</div><span class="motion-divider" data-comparison-divider aria-hidden="true"></span><input class="motion-comparison-control" type="range" min="0" max="100" step="1" value="50" aria-label="前后对比分割位置" data-comparison-input></figure>
</div>.motion-demo.motion-demo--before-after-slider {
box-sizing: border-box;
position: relative;
display: grid;
place-items: center;
width: min(100%, 34rem);
min-height: 15rem;
padding: 2rem;
overflow: hidden;
color: #18181b;
background: #fafafa;
border: 1px solid #e4e4e7;
border-radius: 16px;
isolation: isolate;
}
.motion-demo.motion-demo--before-after-slider *, .motion-demo.motion-demo--before-after-slider *::before, .motion-demo.motion-demo--before-after-slider *::after {
box-sizing: border-box;
}
.motion-demo.motion-demo--before-after-slider .motion-surface {
position: relative;
display: grid;
gap: 0.65rem;
width: min(100%, 18rem);
padding: 1.25rem;
background: #ffffff;
border: 1px solid #e4e4e7;
border-radius: 16px;
box-shadow: none;
}
.motion-demo.motion-demo--before-after-slider .motion-surface strong { font-weight: 500; }
.motion-demo.motion-demo--before-after-slider .motion-line {
display: block;
width: 100%;
height: 0.5rem;
background: #e4e4e7;
border-radius: 999px;
}
.motion-demo.motion-demo--before-after-slider .motion-line:last-child { width: 62%; }
.motion-demo.motion-demo--before-after-slider .motion-button {
position: relative;
min-height: 2.75rem;
padding: 0.75rem 1.1rem;
color: white;
font: inherit;
font-weight: 700;
background: #18181b;
border: 0;
border-radius: 999px;
cursor: pointer;
}
.motion-demo.motion-demo--before-after-slider .motion-button:focus-visible { outline: 3px solid rgb(37 99 235 / 32%); outline-offset: 3px; }
.motion-demo.motion-demo--before-after-slider .motion-action-row {
display: flex;
justify-content: center;
gap: 0.5rem;
margin-top: 0.85rem;
}
.motion-demo.motion-demo--before-after-slider .motion-replay-scene {
width: min(100%, 22rem);
display: grid;
place-items: center;
}
.motion-demo.motion-demo--before-after-slider .motion-pausable-scene {
width: min(100%, 22rem);
display: grid;
place-items: center;
}
.motion-demo.motion-demo--before-after-slider button.motion-surface {
color: inherit;
font: inherit;
text-align: start;
cursor: pointer;
}
.motion-demo.motion-demo--before-after-slider .motion-replay-button,
.motion-demo.motion-demo--before-after-slider .motion-undo-button,
.motion-demo.motion-demo--before-after-slider .motion-dismiss-button,
.motion-demo.motion-demo--before-after-slider .motion-pause-button {
min-height: 2.75rem;
padding: 0.65rem 0.9rem;
color: #18181b;
font: 650 0.78rem/1 ui-sans-serif, system-ui, sans-serif;
background: #ffffff;
border: 1px solid #d4d4d8;
border-radius: 8px;
cursor: pointer;
}
.motion-demo.motion-demo--before-after-slider .motion-replay-button:focus-visible,
.motion-demo.motion-demo--before-after-slider .motion-undo-button:focus-visible,
.motion-demo.motion-demo--before-after-slider .motion-dismiss-button:focus-visible,
.motion-demo.motion-demo--before-after-slider .motion-pause-button:focus-visible,
.motion-demo.motion-demo--before-after-slider [data-reorder-item]:focus-visible,
.motion-demo.motion-demo--before-after-slider [data-swipe-target]:focus-visible {
outline: 3px solid rgb(37 99 235 / 32%);
outline-offset: 3px;
}
.motion-demo.motion-demo--before-after-slider .motion-status {
position: absolute;
width: 1px;
height: 1px;
padding: 0;
margin: -1px;
overflow: hidden;
clip: rect(0, 0, 0, 0);
white-space: nowrap;
border: 0;
}
.motion-demo.motion-demo--before-after-slider .motion-ripple-ink {
position: absolute;
width: 12px;
height: 12px;
pointer-events: none;
background: rgb(255 255 255 / 72%);
border-radius: 50%;
transform: translate(-50%, -50%) scale(0.95);
opacity: 0;
}
.motion-demo.motion-demo--before-after-slider .motion-state-stack { position: relative; width: min(100%, 18rem); height: 9rem; }
.motion-demo.motion-demo--before-after-slider .motion-state { position: absolute; inset: 0; display: grid; place-items: center; padding: 1rem; background: #ffffff; border: 1px solid #e4e4e7; border-radius: 16px; }
.motion-demo.motion-demo--before-after-slider .motion-state--to { background: #18181b; color: white; }
.motion-demo.motion-demo--before-after-slider .motion-scroll-track > span { color: #71717a; font: 600 0.72rem/1.2 ui-monospace, monospace; letter-spacing: 0.08em; text-transform: uppercase; }
.motion-demo.motion-demo--before-after-slider .motion-orbit-item { display: grid; place-items: center; width: 2.5rem; height: 2.5rem; color: white; background: #2563eb; border-radius: 50%; }
.motion-demo.motion-demo--before-after-slider .motion-text-stack { position: relative; width: min(100%, 18rem); min-height: 4rem; }
.motion-demo.motion-demo--before-after-slider svg { width: min(100%, 20rem); height: auto; }
.motion-demo.motion-demo--before-after-slider .motion-comparison { position: relative; width: min(100%, 22rem); aspect-ratio: 16 / 9; overflow: hidden; border-radius: 16px; background: #52525b; }
.motion-demo.motion-demo--before-after-slider .motion-before, .motion-demo.motion-demo--before-after-slider .motion-after { position: absolute; inset: 0; display: grid; place-items: center; color: white; }
.motion-demo.motion-demo--before-after-slider .motion-after { overflow: hidden; background: #2563eb; clip-path: inset(0 50% 0 0); }
.motion-demo.motion-demo--before-after-slider .motion-divider { position: absolute; inset: 0 auto 0 50%; width: 2px; pointer-events: none; background: white; box-shadow: 0 0 0 1px rgb(0 0 0 / 18%); transform: translate3d(-1px, 0, 0); }
.motion-demo.motion-demo--before-after-slider .motion-divider::after { content: "↔"; position: absolute; top: 50%; left: 50%; width: 2.25rem; height: 2.25rem; display: grid; place-items: center; color: #18181b; background: white; border-radius: 50%; transform: translate(-50%, -50%); box-shadow: 0 2px 8px rgb(0 0 0 / 18%); }
.motion-demo.motion-demo--before-after-slider .motion-comparison-control { position: absolute; inset: 0; z-index: 2; width: 100%; height: 100%; margin: 0; cursor: ew-resize; opacity: 0; }
@keyframes motion-before-after-slider-reduced-fade {
from { opacity: 0.84; }
to { opacity: 1; }
}
.force-reduced-motion .motion-demo.motion-demo--before-after-slider {
animation: motion-before-after-slider-reduced-fade 160ms cubic-bezier(0.23, 1, 0.32, 1) both !important;
}
.force-reduced-motion .motion-demo.motion-demo--before-after-slider *,
.force-reduced-motion .motion-demo.motion-demo--before-after-slider *::before,
.force-reduced-motion .motion-demo.motion-demo--before-after-slider *::after {
animation: none !important;
animation-delay: 0ms !important;
animation-iteration-count: 1 !important;
transition-property: opacity, color, background-color, border-color !important;
transition-duration: 160ms !important;
transition-delay: 0ms !important;
scroll-behavior: auto !important;
}
.force-reduced-motion .motion-demo.motion-demo--before-after-slider .motion-button,
.force-reduced-motion .motion-demo.motion-demo--before-after-slider [data-reorder-item],
.force-reduced-motion .motion-demo.motion-demo--before-after-slider [data-swipe-target],
.force-reduced-motion .motion-demo.motion-demo--before-after-slider [data-spring-target] {
transform: none !important;
}
.force-reduced-motion .motion-demo.motion-demo--before-after-slider .motion-path { stroke-dashoffset: 0 !important; }
.force-reduced-motion .motion-demo.motion-demo--before-after-slider .motion-word--from { opacity: 0 !important; visibility: hidden; }
.force-reduced-motion .motion-demo.motion-demo--before-after-slider .motion-word:not(.motion-word--from) { opacity: 1 !important; filter: none !important; transform: none !important; }
@media (prefers-reduced-motion: reduce) {
.motion-demo.motion-demo--before-after-slider {
animation: motion-before-after-slider-reduced-fade 160ms cubic-bezier(0.23, 1, 0.32, 1) both !important;
}
.motion-demo.motion-demo--before-after-slider *, .motion-demo.motion-demo--before-after-slider *::before, .motion-demo.motion-demo--before-after-slider *::after {
animation: none !important;
animation-delay: 0ms !important;
animation-iteration-count: 1 !important;
transition-property: opacity, color, background-color, border-color !important;
transition-duration: 160ms !important;
transition-delay: 0ms !important;
scroll-behavior: auto !important;
}
.motion-demo.motion-demo--before-after-slider .motion-button,
.motion-demo.motion-demo--before-after-slider [data-reorder-item],
.motion-demo.motion-demo--before-after-slider [data-swipe-target],
.motion-demo.motion-demo--before-after-slider [data-spring-target] {
transform: none !important;
}
.motion-demo.motion-demo--before-after-slider .motion-path { stroke-dashoffset: 0 !important; }
.motion-demo.motion-demo--before-after-slider .motion-word--from { opacity: 0 !important; visibility: hidden; }
.motion-demo.motion-demo--before-after-slider .motion-word:not(.motion-word--from) { opacity: 1 !important; filter: none !important; transform: none !important; }
}(() => {
const config = {
"id": "before-after-slider",
"duration": 180,
"distance": 72,
"resistance": 65,
"position": 50,
"stiffness": 220,
"damping": 24,
"mass": 1,
"velocity": 0,
"rippleSize": 220,
"rippleOpacity": 24,
"dragScale": 103,
"autoplay": false
};
const mount = (root, config) => {
const cleanups = [];
const addCleanup = (callback) => cleanups.push(callback);
const cleanup = () => {
for (let index = cleanups.length - 1; index >= 0; index -= 1) {
try { cleanups[index](); } catch { /* keep cleanup reentrant */ }
}
cleanups.length = 0;
};
const on = (target, type, listener, options) => {
target.addEventListener(type, listener, options);
addCleanup(() => target.removeEventListener(type, listener, options));
};
const reduced = () => root.closest(".force-reduced-motion") !== null ||
window.matchMedia("(prefers-reduced-motion: reduce)").matches;
const watchReduced = (callback) => {
const media = window.matchMedia("(prefers-reduced-motion: reduce)");
const notify = () => callback(reduced());
media.addEventListener("change", notify);
const observer = typeof MutationObserver === "undefined" ? null : new MutationObserver(notify);
let ancestor = root;
while (observer && ancestor) {
observer.observe(ancestor, { attributes: true, attributeFilter: ["class"] });
ancestor = ancestor.parentElement;
}
addCleanup(() => {
media.removeEventListener("change", notify);
if (observer) observer.disconnect();
});
};
const comparison = root.querySelector("[data-comparison]");
const after = root.querySelector("[data-comparison-after]");
const divider = root.querySelector("[data-comparison-divider]");
const input = root.querySelector("[data-comparison-input]");
if (!comparison || !after || !divider || !input) return cleanup;
const initial = {
value: input.value,
clipPath: after.style.clipPath,
insetInlineStart: divider.style.insetInlineStart,
transform: divider.style.transform,
valueText: input.getAttribute("aria-valuetext")
};
const update = () => {
const value = Math.min(100, Math.max(0, Number(input.value || config.position)));
after.style.clipPath = "inset(0 " + String(100 - value) + "% 0 0)";
divider.style.insetInlineStart = String(value) + "%";
divider.style.transform = "translate3d(-1px, 0, 0)";
input.setAttribute("aria-valuetext", String(Math.round(value)) + "%");
};
const observer = typeof ResizeObserver === "undefined" ? null : new ResizeObserver(update);
addCleanup(() => {
if (observer) observer.disconnect();
input.value = initial.value;
after.style.clipPath = initial.clipPath;
divider.style.insetInlineStart = initial.insetInlineStart;
divider.style.transform = initial.transform;
if (initial.valueText === null) input.removeAttribute("aria-valuetext");
else input.setAttribute("aria-valuetext", initial.valueText);
});
on(input, "input", update);
if (observer) observer.observe(comparison);
update();
return cleanup;
};
document.querySelectorAll("[data-motion=\"before-after-slider\"]").forEach((root) => {
const cleanupKey = "__motionLexiconCleanup";
if (typeof root[cleanupKey] === "function") root[cleanupKey]();
root[cleanupKey] = mount(root, config);
});
})();before-after-sliderA draggable boundary changes the visible share of two aligned layers for direct comparison.
通过可拖动分割线在两张叠放图片之间擦拭切换,以便对比。
保留可操作分割线,取消位置补间;键盘和指针仍即时更新静态裁切。
| 参数 | 范围 / 选项 | 默认值 | 作用 |
|---|---|---|---|
position | 10%–90% | 50% | 调节分割位置。 |
duration | 80ms–1200ms | 180ms | 控制一次动效完成所需的时间。 |