first

node_modules/vant/lib/utils/dom/scroll.js

@@ -0,0 +1,89 @@
+"use strict";
+
+exports.__esModule = true;
+exports.getScroller = getScroller;
+exports.getScrollTop = getScrollTop;
+exports.setScrollTop = setScrollTop;
+exports.getRootScrollTop = getRootScrollTop;
+exports.setRootScrollTop = setRootScrollTop;
+exports.getElementTop = getElementTop;
+exports.getVisibleHeight = getVisibleHeight;
+exports.getVisibleTop = getVisibleTop;
+
+function isWindow(val) {
+  return val === window;
+} // get nearest scroll element
+// https://github.com/vant-ui/vant/issues/3823
+
+
+var overflowScrollReg = /scroll|auto|overlay/i;
+
+function getScroller(el, root) {
+  if (root === void 0) {
+    root = window;
+  }
+
+  var node = el;
+
+  while (node && node.tagName !== 'HTML' && node.tagName !== 'BODY' && node.nodeType === 1 && node !== root) {
+    var _window$getComputedSt = window.getComputedStyle(node),
+        overflowY = _window$getComputedSt.overflowY;
+
+    if (overflowScrollReg.test(overflowY)) {
+      return node;
+    }
+
+    node = node.parentNode;
+  }
+
+  return root;
+}
+
+function getScrollTop(el) {
+  var top = 'scrollTop' in el ? el.scrollTop : el.pageYOffset; // iOS scroll bounce cause minus scrollTop
+
+  return Math.max(top, 0);
+}
+
+function setScrollTop(el, value) {
+  if ('scrollTop' in el) {
+    el.scrollTop = value;
+  } else {
+    el.scrollTo(el.scrollX, value);
+  }
+}
+
+function getRootScrollTop() {
+  return window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop || 0;
+}
+
+function setRootScrollTop(value) {
+  setScrollTop(window, value);
+  setScrollTop(document.body, value);
+} // get distance from element top to page top or scroller top
+
+
+function getElementTop(el, scroller) {
+  if (isWindow(el)) {
+    return 0;
+  }
+
+  var scrollTop = scroller ? getScrollTop(scroller) : getRootScrollTop();
+  return el.getBoundingClientRect().top + scrollTop;
+}
+
+function getVisibleHeight(el) {
+  if (isWindow(el)) {
+    return el.innerHeight;
+  }
+
+  return el.getBoundingClientRect().height;
+}
+
+function getVisibleTop(el) {
+  if (isWindow(el)) {
+    return 0;
+  }
+
+  return el.getBoundingClientRect().top;
+}