add scroll bar offset function

AKAChing · web-flow · commit b74abb96634b · 2020-03-09T13:37:03.000+08:00
diff --git a/ScrollBarOffset/index.js b/ScrollBarOffset/index.js
@@ -0,0 +1,14 @@
+export function addScrollBarOffsetWidth(className) {
+  const isTouchDevice = "ontouchstart" in window
+  if (!isTouchDevice) { // 如果是触摸屏则滚动条不占据空间 不进行操作
+    let observer = new MutationObserver(mutations => {
+      const flag = mutations.some(mutation => mutation.target.className == className) // 判断是否含有目标属性
+      if (flag) {
+        document.querySelector('body').style.paddingRight = 17 + 'px' // 有overflow属性则给body添加padding-right
+      } else {
+        document.querySelector('body').style.paddingRight = 0 + 'px' // 没有则归零
+      }
+    })
+    observer.observe(document.querySelector('body'), { attributes: true, attributeFilter: ['class'] }) 
+  }
+}
