theme-starter

themes/starter/components/BackToTopButton.js

@@ -0,0 +1,67 @@
+import throttle from 'lodash.throttle';
+import { useCallback, useEffect } from 'react'
+
+export const BackToTopButton = () => {
+  useEffect(() => {
+    // ====== scroll top js
+    function scrollTo(element, to = 0, duration = 500) {
+      const start = element.scrollTop;
+      const change = to - start;
+      const increment = 20;
+      let currentTime = 0;
+
+      const animateScroll = () => {
+        currentTime += increment;
+
+        const val = Math.easeInOutQuad(currentTime, start, change, duration);
+
+        element.scrollTop = val;
+
+        if (currentTime < duration) {
+          setTimeout(animateScroll, increment);
+        }
+      };
+
+      animateScroll();
+    }
+
+    Math.easeInOutQuad = function (t, b, c, d) {
+      t /= d / 2;
+      if (t < 1) return (c / 2) * t * t + b;
+      t--;
+      return (-c / 2) * (t * (t - 2) - 1) + b;
+    };
+    const backToTop = document.querySelector('.back-to-top')
+    if (backToTop) {
+      backToTop.onclick = () => {
+        scrollTo(document.documentElement);
+      };
+    }
+
+    window.addEventListener('scroll', navBarScollListener)
+    return () => {
+      window.removeEventListener('scroll', navBarScollListener)
+    }
+  }, [])
+
+  // 滚动监听
+  const throttleMs = 200
+  const navBarScollListener = useCallback(
+    throttle(() => {
+      const scrollY = window.scrollY;
+      // 显示或隐藏返回顶部按钮
+      const backToTop = document.querySelector('.back-to-top');
+      if (backToTop) {
+        backToTop.style.display = scrollY > 50 ? 'flex' : 'none';
+      }
+    }, throttleMs)
+  )
+
+  return <>
+        {/* <!-- ====== Back To Top Start --> */}
+        <a className="back-to-top fixed bottom-8 left-auto right-8 z-[999] hidden h-10 w-10 items-center justify-center rounded-md bg-primary text-white shadow-md transition duration-300 ease-in-out hover:bg-dark">
+            <span className="mt-[6px] h-3 w-3 rotate-45 border-l border-t border-white" ></span>
+         </a>
+    {/* <!-- ====== Back To Top End --> */}
+    </>
+}