提交

src/components/ElMenu/utils/scroll-into-view.js

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+import Vue from 'vue';
+
+export default function scrollIntoView(container, selected) {
+  if (Vue.prototype.$isServer) return;
+
+  if (!selected) {
+    container.scrollTop = 0;
+    return;
+  }
+
+  const offsetParents = [];
+  let pointer = selected.offsetParent;
+  while (pointer && container !== pointer && container.contains(pointer)) {
+    offsetParents.push(pointer);
+    pointer = pointer.offsetParent;
+  }
+  const top = selected.offsetTop + offsetParents.reduce((prev, curr) => (prev + curr.offsetTop), 0);
+  const bottom = top + selected.offsetHeight;
+  const viewRectTop = container.scrollTop;
+  const viewRectBottom = viewRectTop + container.clientHeight;
+
+  if (top < viewRectTop) {
+    container.scrollTop = top;
+  } else if (bottom > viewRectBottom) {
+    container.scrollTop = bottom - container.clientHeight;
+  }
+}