feat 搭建架构骨架

src/composables/useScroll.ts

@@ -0,0 +1,26 @@
+import { computed, onMounted, onUnmounted, ref, type ComputedRef, type Ref } from 'vue'
+
+/** 滚动监听/吸顶/回到顶部 */
+export function useScroll(threshold = 200): {
+  scrollY: Ref<number>
+  isAtTop: ComputedRef<boolean>
+  showBackTop: ComputedRef<boolean>
+  scrollToTop: (smooth?: boolean) => void
+} {
+  const scrollY = ref(0)
+  const isAtTop = computed(() => scrollY.value <= 0)
+  const showBackTop = computed(() => scrollY.value > threshold)
+
+  function onScroll(): void {
+    scrollY.value = window.scrollY
+  }
+
+  function scrollToTop(smooth = true): void {
+    window.scrollTo({ top: 0, behavior: smooth ? 'smooth' : 'auto' })
+  }
+
+  onMounted(() => window.addEventListener('scroll', onScroll, { passive: true }))
+  onUnmounted(() => window.removeEventListener('scroll', onScroll))
+
+  return { scrollY, isAtTop, showBackTop, scrollToTop }
+}