From a0b27a806e593e2d00d3bff8fc22f8497c360679 Mon Sep 17 00:00:00 2001
From: pipipi-pikachu <pipipi_pikachu@163.com>
Date: Fri, 13 May 2022 23:03:11 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E5=8A=A8=E7=94=BB=E5=BA=8F=E5=88=97?=
 =?UTF-8?q?=E7=AC=AC=E4=B8=80=E9=A1=B9=E4=B8=BA=E9=9D=9E=E4=B8=BB=E5=8A=A8?=
 =?UTF-8?q?=E8=A7=A6=E5=8F=91=E6=97=B6=E5=BC=82=E5=B8=B8=E3=80=81=E6=92=A4?=
 =?UTF-8?q?=E5=9B=9E=E6=9C=AA=E6=92=AD=E6=94=BE=E7=9A=84=E9=A1=B5=E9=9D=A2?=
 =?UTF-8?q?=E6=97=B6=E5=BC=82=E5=B8=B8?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/store/slides.ts                   | 10 +++++-----
 src/views/Screen/hooks/useExecPlay.ts | 12 +++++++++++-
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/store/slides.ts b/src/store/slides.ts
index 72e71eb2..13d50e11 100644
--- a/src/store/slides.ts
+++ b/src/store/slides.ts
@@ -63,17 +63,17 @@ export const useSlidesStore = defineStore('slides', {
 
       const formatedAnimations: FormatedAnimation[] = []
       for (const animation of animations) {
-        if (animation.trigger === 'click') {
+        if (animation.trigger === 'click' || !formatedAnimations.length) {
           formatedAnimations.push({ animations: [animation], autoNext: false })
         }
-        if (animation.trigger === 'meantime') {
-          const last = formatedAnimations[formatedAnimations.length - 1] || { animations: [], autoNext: false }
+        else if (animation.trigger === 'meantime') {
+          const last = formatedAnimations[formatedAnimations.length - 1]
           last.animations = last.animations.filter(item => item.elId !== animation.elId)
           last.animations.push(animation)
           formatedAnimations[formatedAnimations.length - 1] = last
         }
-        if (animation.trigger === 'auto') {
-          const last = formatedAnimations[formatedAnimations.length - 1] || { animations: [], autoNext: false }
+        else if (animation.trigger === 'auto') {
+          const last = formatedAnimations[formatedAnimations.length - 1]
           last.autoNext = true
           formatedAnimations[formatedAnimations.length - 1] = last
           formatedAnimations.push({ animations: [animation], autoNext: false })
diff --git a/src/views/Screen/hooks/useExecPlay.ts b/src/views/Screen/hooks/useExecPlay.ts
index ee5ef92b..a799e73d 100644
--- a/src/views/Screen/hooks/useExecPlay.ts
+++ b/src/views/Screen/hooks/useExecPlay.ts
@@ -13,8 +13,13 @@ export default () => {
 
   // 当前页的元素动画执行到的位置
   const animationIndex = ref(0)
+
+  // 动画执行状态
   const inAnimation = ref(false)
 
+  // 最小已播放页面索引
+  const playedSlidesMinIndex = ref(slideIndex.value)
+
   // 执行元素动画
   const runAnimation = () => {
     // 正在执行动画时，禁止其他新的动画开始
@@ -102,13 +107,18 @@ export default () => {
   // 向上/向下播放
   // 遇到元素动画时，优先执行动画播放，无动画则执行翻页
   // 向上播放遇到动画时，仅撤销到动画执行前的状态，不需要反向播放动画
+  // 撤回到上一页时，若该页从未播放过（意味着不存在动画状态），需要将动画索引置为最小值（初始状态），否则置为最大值（最终状态）
   const execPrev = () => {
     if (formatedAnimations.value.length && animationIndex.value > 0) {
       revokeAnimation()
     }
     else if (slideIndex.value > 0) {
       slidesStore.updateSlideIndex(slideIndex.value - 1)
-      animationIndex.value = formatedAnimations.value.length
+      if (slideIndex.value < playedSlidesMinIndex.value) {
+        animationIndex.value = 0
+        playedSlidesMinIndex.value = slideIndex.value
+      }
+      else animationIndex.value = formatedAnimations.value.length
       inAnimation.value = false
     }
     else {