From 9362cb704f119d700010cea1a7ce7357e2ba95f2 Mon Sep 17 00:00:00 2001
From: pany <939630029@qq.com>
Date: Thu, 23 Mar 2023 11:27:07 +0800
Subject: [PATCH] feat: 'tag' outside the viewport is automatically moved to
 the viewable area

---
 src/layout/components/TagsView/ScrollPane.vue | 68 +++++++++++++++++--
 src/layout/components/TagsView/index.vue      |  7 +-
 2 files changed, 67 insertions(+), 8 deletions(-)

diff --git a/src/layout/components/TagsView/ScrollPane.vue b/src/layout/components/TagsView/ScrollPane.vue
index c5f25cd..4f2434f 100644
--- a/src/layout/components/TagsView/ScrollPane.vue
+++ b/src/layout/components/TagsView/ScrollPane.vue
@@ -1,10 +1,19 @@
 <script lang="ts" setup>
-import { computed, ref } from "vue"
+import { type PropType, computed, ref, watch, nextTick } from "vue"
+import { RouterLink, useRoute } from "vue-router"
 import { ElScrollbar } from "element-plus"
 import { ArrowLeft, ArrowRight } from "@element-plus/icons-vue"
 import { useSettingsStore } from "@/store/modules/settings"
 import Screenfull from "@/components/Screenfull/index.vue"
 
+const props = defineProps({
+  tagRefs: {
+    type: Object as PropType<InstanceType<typeof RouterLink>[]>,
+    required: true
+  }
+})
+
+const route = useRoute()
 const settingsStore = useSettingsStore()
 
 const scrollbarRef = ref<InstanceType<typeof ElScrollbar>>()
@@ -20,6 +29,7 @@ const scroll = ({ scrollLeft }: { scrollLeft: number }) => {
   currentScrollLeft = scrollLeft
 }
 
+/** 鼠标滚轮滚动时触发 */
 const wheelScroll = ({ deltaY }: WheelEvent) => {
   if (/^-/.test(deltaY.toString())) {
     scrollTo("left")
@@ -28,24 +38,70 @@ const wheelScroll = ({ deltaY }: WheelEvent) => {
   }
 }
 
-/** 点击滚动 */
-const scrollTo = (direction: "left" | "right") => {
-  let scrollLeft = 0
+/** 获取可能需要的宽度 */
+const getWidth = () => {
   /** 可滚动内容的长度 */
   const scrollbarContentRefWidth = scrollbarContentRef.value!.clientWidth
   /** 滚动可视区宽度 */
   const scrollbarRefWidth = scrollbarRef.value!.wrapRef!.clientWidth
   /** 最后剩余可滚动的宽度 */
   const lastDistance = scrollbarContentRefWidth - scrollbarRefWidth - currentScrollLeft
+
+  return { scrollbarContentRefWidth, scrollbarRefWidth, lastDistance }
+}
+
+/** 左右滚动 */
+const scrollTo = (direction: "left" | "right", distance: number = translateDistance) => {
+  let scrollLeft = 0
+  const { scrollbarContentRefWidth, scrollbarRefWidth, lastDistance } = getWidth()
   // 没有横向滚动条，直接结束
   if (scrollbarRefWidth > scrollbarContentRefWidth) return
   if (direction === "left") {
-    scrollLeft = Math.max(0, currentScrollLeft - translateDistance)
+    scrollLeft = Math.max(0, currentScrollLeft - distance)
   } else {
-    scrollLeft = Math.min(currentScrollLeft + translateDistance, currentScrollLeft + lastDistance)
+    scrollLeft = Math.min(currentScrollLeft + distance, currentScrollLeft + lastDistance)
   }
   scrollbarRef.value!.setScrollLeft(scrollLeft)
 }
+
+/** 移动到目标位置 */
+const moveTo = () => {
+  const tagRefs = props.tagRefs
+  for (let i = 0; i < tagRefs.length; i++) {
+    // @ts-ignore
+    if (route.path === tagRefs[i].$props.to.path) {
+      // @ts-ignore
+      const el: HTMLElement = tagRefs[i].$el
+      const offsetWidth = el.offsetWidth
+      const offsetLeft = el.offsetLeft
+      const { scrollbarRefWidth } = getWidth()
+      // 当前 tag 在可视区域左边时
+      if (offsetLeft < currentScrollLeft) {
+        const distance = currentScrollLeft - offsetLeft
+        scrollTo("left", distance)
+        return
+      }
+      // 当前 tag 在可视区域右边时
+      const width = scrollbarRefWidth + currentScrollLeft - offsetWidth
+      if (offsetLeft > width) {
+        const distance = offsetLeft - width
+        scrollTo("right", distance)
+        return
+      }
+    }
+  }
+}
+
+watch(
+  route,
+  () => {
+    nextTick(moveTo)
+  },
+  {
+    deep: true
+  }
+)
+
 const showScreenfull = computed(() => {
   return settingsStore.showScreenfull
 })
diff --git a/src/layout/components/TagsView/index.vue b/src/layout/components/TagsView/index.vue
index 97338b9..a49fb22 100644
--- a/src/layout/components/TagsView/index.vue
+++ b/src/layout/components/TagsView/index.vue
@@ -1,6 +1,6 @@
 <script lang="ts" setup>
 import { getCurrentInstance, onMounted, ref, watch } from "vue"
-import { type RouteRecordRaw, useRoute, useRouter } from "vue-router"
+import { type RouteRecordRaw, RouterLink, useRoute, useRouter } from "vue-router"
 import { type ITagView, useTagsViewStore } from "@/store/modules/tags-view"
 import { usePermissionStore } from "@/store/modules/permission"
 import ScrollPane from "./ScrollPane.vue"
@@ -13,6 +13,8 @@ const route = useRoute()
 const tagsViewStore = useTagsViewStore()
 const permissionStore = usePermissionStore()
 
+const tagRefs = ref<InstanceType<typeof RouterLink>[]>([])
+
 const visible = ref(false)
 const top = ref(0)
 const left = ref(0)
@@ -161,8 +163,9 @@ onMounted(() => {
 
 <template>
   <div class="tags-view-container">
-    <ScrollPane class="tags-view-wrapper">
+    <ScrollPane class="tags-view-wrapper" :tagRefs="tagRefs">
       <router-link
+        ref="tagRefs"
         v-for="tag in tagsViewStore.visitedViews"
         :key="tag.path"
         :class="isActive(tag) ? 'active' : ''"