MyPageRight.vb 23 KB

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  1. Public Class MyPageRight
  2. Inherits AdornerDecorator
  3. Public PageUuid As Integer = GetUuid()
  4. '“返回顶部” 按钮检测的滚动区域
  5. Public Property PanScroll As String '需要在 Loaded 之后才能获取到控件,所以不能用 Binding 直接绑定(#6664)
  6. Get
  7. Return GetValue(PanScrollProperty)
  8. End Get
  9. Set(value As String)
  10. SetValue(PanScrollProperty, value)
  11. End Set
  12. End Property
  13. Private Shared ReadOnly PanScrollProperty =
  14. DependencyProperty.Register("PanScroll", GetType(String), GetType(MyPageRight), New PropertyMetadata(Nothing))
  15. '当前状态
  16. Public Enum PageStates
  17. Empty '默认状态,页面全空
  18. LoaderWait '加载环初始等待
  19. LoaderEnter '加载环进入动画
  20. LoaderStayForce '加载环正常显示(强制等待)
  21. LoaderStay '加载环正常显示
  22. LoaderExit '加载环退出动画
  23. ContentEnter '内容进入动画
  24. ContentStay '内容正常显示
  25. ContentExit '刷新导致的全部退出动画,或页面内容退出(子页面更改)导致的全部退出动画
  26. PageExit '切换页面导致的全部退出动画
  27. End Enum
  28. Private _PageState As PageStates = PageStates.Empty
  29. Public Property PageState As PageStates
  30. Get
  31. Return _PageState
  32. End Get
  33. Set(value As PageStates)
  34. If _PageState = value Then Return
  35. _PageState = value
  36. If ModeDebug Then Log("[UI] 页面状态切换为 " & GetStringFromEnum(value))
  37. End Set
  38. End Property
  39. #Region "加载器"
  40. Private PageLoader As LoaderBase
  41. Private PageLoaderInputInvoke
  42. Private PageLoaderUi As MyLoading
  43. Private PanLoader As FrameworkElement
  44. Private PanContent As FrameworkElement
  45. Private PanAlways As FrameworkElement
  46. Private PageLoaderAutoRun As Boolean
  47. '初始化
  48. ''' <summary>
  49. ''' 表明页面存在需要在后台执行的加载器。
  50. ''' </summary>
  51. ''' <param name="LoaderUi">MyLoading 控件。</param>
  52. ''' <param name="PanLoader">MyLoading 控件对应的卡片。</param>
  53. ''' <param name="PanContent">加载结束后出现的内容容器。</param>
  54. ''' <param name="PanAlways">无论是否在加载总是要显示的容器。可以为 Nothing。</param>
  55. ''' <param name="RealLoader">在工作线程执行的加载器。</param>
  56. ''' <param name="FinishedInvoke">当加载器执行完成,在 UI 线程触发的 UI 初始化事件。</param>
  57. Public Sub PageLoaderInit(LoaderUi As MyLoading, PanLoader As FrameworkElement, PanContent As FrameworkElement, PanAlways As FrameworkElement,
  58. RealLoader As LoaderBase,
  59. Optional FinishedInvoke As Action(Of LoaderBase) = Nothing, Optional InputInvoke As Func(Of Object) = Nothing,
  60. Optional AutoRun As Boolean = True)
  61. '初始化参数
  62. Me.PanLoader = PanLoader
  63. Me.PanContent = PanContent
  64. Me.PanAlways = PanAlways
  65. Me.PageLoader = RealLoader
  66. Me.PageLoaderUi = LoaderUi
  67. Me.PageLoaderInputInvoke = InputInvoke
  68. Me.PageLoaderAutoRun = AutoRun
  69. '添加结束 Invoke
  70. If FinishedInvoke IsNot Nothing Then
  71. AddHandler RealLoader.PreviewFinish,
  72. Sub()
  73. Do While PageState = MyPageRight.PageStates.PageExit OrElse PageState = MyPageRight.PageStates.ContentExit
  74. Thread.Sleep(10) '不在退出动画时执行 UI 线程操作,避免退出动画被重置
  75. Loop
  76. RunInUiWait(Sub() FinishedInvoke(RealLoader))
  77. Thread.Sleep(20) '由于大量初始化控件会导致掉帧,延迟触发 State 改变事件
  78. End Sub
  79. End If
  80. AddHandler RealLoader.OnStateChangedUi, Sub(Loader As LoaderBase, NewState As LoadState, OldState As LoadState) RunInUi(Sub() PageLoaderState(Loader, NewState, OldState))
  81. '隐藏 UI
  82. PanLoader.Visibility = Visibility.Collapsed
  83. PanContent.Visibility = Visibility.Collapsed
  84. If PanAlways IsNot Nothing Then PanAlways.Visibility = Visibility.Collapsed
  85. '初次运行加载器
  86. If PageLoaderAutoRun Then
  87. If PageLoader.GetType.Name.StartsWithF("LoaderTask") Then
  88. PageLoader.Start(CType(PageLoader, Object).StartGetInput(Nothing, PageLoaderInputInvoke))
  89. Else
  90. Dim Input = Nothing
  91. If PageLoaderInputInvoke IsNot Nothing Then Input = PageLoaderInputInvoke()
  92. PageLoader.Start(Input)
  93. End If
  94. End If
  95. If PageLoader.State = LoadState.Finished AndAlso FinishedInvoke IsNot Nothing Then
  96. RunInUiWait(Sub() FinishedInvoke(RealLoader)) '加载器已提前完成,直接触发事件
  97. End If
  98. '设置加载环
  99. PageLoaderUi.State = RealLoader
  100. AddHandler PageLoaderUi.Click, Sub() If RealLoader.State = LoadState.Failed Then PageLoaderRestart() '点击重试事件
  101. End Sub
  102. '重试
  103. Public Sub PageLoaderRestart(Optional Input As Object = Nothing, Optional IsForceRestart As Boolean = True) '由外部调用的重试
  104. If Not PageLoaderAutoRun Then Return
  105. If PageLoader.GetType.Name.StartsWithF("LoaderTask") Then
  106. PageLoader.Start(CType(PageLoader, Object).StartGetInput(Input, PageLoaderInputInvoke), IsForceRestart:=IsForceRestart)
  107. Else
  108. If Input Is Nothing AndAlso PageLoaderInputInvoke IsNot Nothing Then Input = PageLoaderInputInvoke()
  109. PageLoader.Start(Input, IsForceRestart:=IsForceRestart)
  110. End If
  111. End Sub
  112. #End Region
  113. #Region "事件"
  114. '外部触发的事件
  115. ''' <summary>
  116. ''' 需要切换到当前页面,并且原本的 Loaded 事件已执行完成。
  117. ''' 需要根据加载器状态,从 Empty 切换到 ContentEnter、LoaderWait、LoaderEnter。
  118. ''' </summary>
  119. Public Sub PageOnEnter()
  120. If ModeDebug Then Log("[UI] 已触发 PageOnEnter")
  121. RaiseEvent PageEnter()
  122. Select Case PageState
  123. Case PageStates.Empty
  124. If PageLoader Is Nothing OrElse PageLoader.State = LoadState.Finished OrElse PageLoader.State = LoadState.Waiting OrElse PageLoader.State = LoadState.Interrupted Then
  125. '如果加载器在进入页面时不启动(例如联机),那么在此时就会有 State = Waiting
  126. PageState = PageStates.ContentEnter
  127. TriggerEnterAnimation(PanAlways, If(PanContent, Child))
  128. ElseIf PageLoader.State = LoadState.Loading Then
  129. PageState = PageStates.LoaderWait
  130. AniStart(AaCode(AddressOf PageOnLoaderWaitFinished, 400), "PageRight PageChange " & PageUuid)
  131. Else 'PageLoader.State = LoadState.Failed
  132. PageState = PageStates.LoaderEnter
  133. TriggerEnterAnimation(PanAlways, PanLoader)
  134. End If
  135. Case PageStates.ContentExit
  136. '和上面的一样,但是不管 PanAlways
  137. If PageLoader Is Nothing OrElse PageLoader.State = LoadState.Finished OrElse PageLoader.State = LoadState.Waiting OrElse PageLoader.State = LoadState.Interrupted Then
  138. PageState = PageStates.ContentEnter
  139. TriggerEnterAnimation(If(PanContent, Child))
  140. ElseIf PageLoader.State = LoadState.Loading Then
  141. PageState = PageStates.LoaderWait
  142. AniStart(AaCode(AddressOf PageOnLoaderWaitFinished, 400), "PageRight PageChange " & PageUuid)
  143. Else 'PageLoader.State = LoadState.Failed
  144. PageState = PageStates.LoaderEnter
  145. TriggerEnterAnimation(PanLoader)
  146. End If
  147. Case PageStates.ContentEnter
  148. '重复调用 PageOnEnter,直接忽略
  149. Case Else
  150. Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnEnter 事件。")
  151. End Select
  152. End Sub
  153. Public Event PageEnter()
  154. ''' <summary>
  155. ''' 需要切换到其他页面。
  156. ''' 需要立即切换至 PageExit 或 Empty。
  157. ''' </summary>
  158. Public Sub PageOnExit()
  159. If ModeDebug Then Log("[UI] 已触发 PageOnExit")
  160. RaiseEvent PageExit()
  161. Select Case PageState
  162. Case PageStates.ContentEnter, PageStates.ContentStay
  163. PageState = PageStates.PageExit
  164. TriggerExitAnimation(PanAlways, If(PanContent, Child))
  165. Case PageStates.LoaderEnter, PageStates.LoaderStayForce, PageStates.LoaderStay
  166. PageState = PageStates.PageExit
  167. TriggerExitAnimation(PanAlways, PanLoader)
  168. Case PageStates.LoaderWait
  169. PageState = PageStates.PageExit
  170. TriggerExitAnimation(PanAlways)
  171. Case PageStates.LoaderExit, PageStates.ContentExit
  172. PageState = PageStates.PageExit
  173. If PanAlways IsNot Nothing Then TriggerExitAnimation(PanAlways, If(PanContent, Child))
  174. Case PageStates.PageExit, PageStates.Empty
  175. End Select
  176. End Sub
  177. Public Event PageExit()
  178. ''' <summary>
  179. ''' 即将切换到其他页面,需要强制完成页面状态清理。
  180. ''' 需要立即切换至 Empty。
  181. ''' </summary>
  182. Public Sub PageOnForceExit()
  183. If PageState = PageStates.Empty Then Return
  184. If ModeDebug Then Log("[UI] 已触发 PageOnForceExit")
  185. PageState = PageStates.Empty
  186. AniStop("PageRight PageChange " & PageUuid)
  187. '由于动画会被强制中止,所以需要手动进行隐藏
  188. If PageLoader Is Nothing Then
  189. Child.Visibility = Visibility.Collapsed
  190. Else
  191. PanContent.Visibility = Visibility.Collapsed
  192. PanLoader.Visibility = Visibility.Collapsed
  193. If PanAlways IsNot Nothing Then PanAlways.Visibility = Visibility.Collapsed
  194. End If
  195. End Sub
  196. ''' <summary>
  197. ''' PanContent 中的子页面改变,需要让当前内容退出,再显示新的内容。
  198. ''' 需要在 PageEnter 事件确认要显示的子页面有哪些。
  199. ''' </summary>
  200. Public Sub PageOnContentExit()
  201. If ModeDebug Then Log("[UI] 已触发 PageOnContentExit")
  202. If PageLoader IsNot Nothing AndAlso PageLoader.State = LoadState.Loading Then
  203. 'Loading 的加载器可能触发进一步变化,难以预测会触发子页面的动画还是加载器完成的动画
  204. Throw New Exception("在调用 PageOnContentExit 时,加载器不能为 Loading 状态")
  205. End If
  206. Select Case PageState
  207. Case PageStates.ContentEnter, PageStates.ContentStay
  208. PageState = PageStates.ContentExit
  209. TriggerExitAnimation(PanContent)
  210. Case PageStates.LoaderExit
  211. PageState = PageStates.ContentExit
  212. Case PageStates.LoaderEnter, PageStates.LoaderStayForce, PageStates.LoaderStay
  213. PageState = PageStates.ContentExit
  214. TriggerExitAnimation(PanLoader)
  215. Case PageStates.LoaderWait
  216. PageOnEnter()
  217. Case PageStates.Empty
  218. '可能是在离开页面后,其他后台线程调用了本函数,此时不应触发 PageOnEnter()
  219. '例如:在加入联机房间后,切换到其他页面,然后联机房间被解散
  220. If IsLoaded Then PageOnEnter()
  221. End Select
  222. End Sub
  223. '内部触发的事件
  224. ''' <summary>
  225. ''' 逐个进入动画已执行完成。
  226. ''' 需要根据目前状态,从 ContentEnter 切换到 ContentStay,或从 LoaderEnter 切换到 LoaderStayForce。
  227. ''' </summary>
  228. Private Sub PageOnEnterAnimationFinished()
  229. If ModeDebug Then Log("[UI] 已触发 PageOnEnterAnimationFinished")
  230. Select Case PageState
  231. Case PageStates.ContentEnter
  232. PageState = PageStates.ContentStay
  233. Case PageStates.LoaderEnter
  234. PageState = PageStates.LoaderStayForce
  235. AniStart(AaCode(AddressOf PageOnLoaderStayFinished, 400), "PageRight PageChange " & PageUuid)
  236. Case Else
  237. Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnEnterAnimationFinished 事件。")
  238. End Select
  239. End Sub
  240. ''' <summary>
  241. ''' 逐个退出动画已执行完成。
  242. ''' 需要根据目前状态,从 AllExit 切换到 Empty,或从 LoaderExit 切换到 ContentEnter,或从 ContentExit 重新触发 PageOnEnter。
  243. ''' </summary>
  244. Private Sub PageOnExitAnimationFinished()
  245. If ModeDebug Then Log("[UI] 已触发 PageOnExitAnimationFinished")
  246. Select Case PageState
  247. Case PageStates.PageExit
  248. PageState = PageStates.Empty
  249. Case PageStates.ContentExit
  250. PageOnEnter()
  251. Case PageStates.LoaderExit
  252. PageState = PageStates.ContentEnter
  253. TriggerEnterAnimation(PanContent)
  254. Case Else
  255. Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnExitAnimationFinished 事件。")
  256. End Select
  257. End Sub
  258. ''' <summary>
  259. ''' 加载环进入等待已结束。
  260. ''' 需要从 LoaderWait 切换到 LoaderEnter。
  261. ''' </summary>
  262. Private Sub PageOnLoaderWaitFinished()
  263. If ModeDebug Then Log("[UI] 已触发 PageOnLoaderWaitFinished")
  264. Select Case PageState
  265. Case PageStates.LoaderWait
  266. PageState = PageStates.LoaderEnter
  267. If PanAlways IsNot Nothing AndAlso PanAlways.Visibility = Visibility.Collapsed Then
  268. TriggerEnterAnimation(PanAlways, PanLoader)
  269. Else
  270. TriggerEnterAnimation(PanLoader)
  271. End If
  272. Case Else
  273. Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnLoaderWaitFinished 事件。")
  274. End Select
  275. End Sub
  276. ''' <summary>
  277. ''' 加载环展示等待已结束。
  278. ''' 需要从 LoaderStayForce 切换到 LoaderStay 或 LoaderExit。
  279. ''' </summary>
  280. Private Sub PageOnLoaderStayFinished()
  281. If ModeDebug Then Log("[UI] 已触发 PageOnLoaderStayFinished")
  282. Select Case PageState
  283. Case PageStates.LoaderStayForce
  284. If PageLoader.State = LoadState.Finished Then
  285. PageState = PageStates.LoaderExit
  286. TriggerExitAnimation(PanLoader)
  287. Else
  288. PageState = PageStates.LoaderStay
  289. End If
  290. Case Else
  291. Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnLoaderWaitFinished 事件。")
  292. End Select
  293. End Sub
  294. ''' <summary>
  295. ''' 全局加载状态已改变。
  296. ''' </summary>
  297. Private Sub PageLoaderState(sender As Object, NewState As LoadState, OldState As LoadState)
  298. Select Case NewState
  299. Case LoadState.Failed, LoadState.Loading
  300. If OldState = LoadState.Failed OrElse OldState = LoadState.Loading Then Return
  301. If ModeDebug Then Log("[UI] 已触发 PageLoaderState (Start/Refresh)")
  302. '(重新)开始运行
  303. '需要从部分状态切换到 ReloadExit
  304. Select Case PageState
  305. Case PageStates.ContentEnter, PageStates.ContentStay
  306. PageState = PageStates.ContentExit
  307. TriggerExitAnimation(PanContent)
  308. Case PageStates.LoaderExit
  309. PageState = PageStates.ContentExit
  310. End Select
  311. Case LoadState.Finished, LoadState.Interrupted, LoadState.Waiting
  312. If Not (OldState = LoadState.Failed OrElse OldState = LoadState.Loading) Then Return
  313. If ModeDebug Then Log("[UI] 已触发 PageLoaderState (Stop/Interrupt)")
  314. '运行结束
  315. '需要从 LoaderWait 切换到 ContentEnter,或从 LoaderStay 切换到 LoaderExit
  316. Select Case PageState
  317. Case PageStates.LoaderWait
  318. PageState = PageStates.ContentEnter
  319. If PanAlways IsNot Nothing AndAlso PanAlways.Visibility = Visibility.Collapsed Then
  320. TriggerEnterAnimation(PanAlways, PanContent)
  321. Else
  322. TriggerEnterAnimation(PanContent)
  323. End If
  324. Case PageStates.LoaderStay
  325. PageState = PageStates.LoaderExit
  326. TriggerExitAnimation(PanLoader)
  327. End Select
  328. End Select
  329. End Sub
  330. #End Region
  331. #Region "动画"
  332. '逐个进入动画
  333. Public Sub TriggerEnterAnimation(ParamArray Elements As FrameworkElement())
  334. Dim RealElements = Elements.Where(Function(e) e IsNot Nothing)
  335. For Each Element In RealElements
  336. Element.Visibility = Visibility.Visible '页面均处于默认的隐藏状态
  337. Next
  338. Dim AniList As New List(Of AniData)
  339. Dim Delay As Integer = 0
  340. '基础动画
  341. For Each Element In RealElements
  342. For Each Control As FrameworkElement In GetAllAnimControls(Element, True)
  343. '还原被隐藏的卡片的消失动画
  344. Control.IsHitTestVisible = True
  345. If Control.RenderTransform IsNot Nothing AndAlso TypeOf Control.RenderTransform Is TranslateTransform Then Control.RenderTransform = Nothing
  346. Next
  347. For Each Control As FrameworkElement In GetAllAnimControls(Element)
  348. If TypeOf Control Is MyExtraTextButton Then
  349. CType(Control, MyExtraTextButton).Show = True
  350. Else
  351. Control.Opacity = 0
  352. Control.RenderTransform = New TranslateTransform(0, -16)
  353. AniList.Add(AaOpacity(Control, 1, 100, Delay, New AniEaseOutFluent(AniEasePower.Weak)))
  354. AniList.Add(AaTranslateY(Control, 5, 250, Delay, New AniEaseOutFluent))
  355. AniList.Add(AaTranslateY(Control, 11, 350, Delay, New AniEaseOutBack))
  356. Delay += 25
  357. End If
  358. Next
  359. Next
  360. '滚动条动画
  361. Dim Scroll As MyScrollBar = GetFirstScrollViewer(RealElements)
  362. If Scroll IsNot Nothing Then
  363. If TypeOf Scroll.RenderTransform IsNot TranslateTransform Then Scroll.RenderTransform = New TranslateTransform(10, 0)
  364. AniList.Add(AaTranslateX(Scroll, -CType(Scroll.RenderTransform, TranslateTransform).X, 350, 0, New AniEaseOutFluent))
  365. End If
  366. '结束
  367. AniList.Add(AaCode(Sub() PageOnEnterAnimationFinished(),, True))
  368. AniStart(AniList, "PageRight PageChange " & PageUuid, True)
  369. End Sub
  370. '逐个退出动画
  371. Public Sub TriggerExitAnimation(ParamArray Elements As FrameworkElement())
  372. Dim RealElements = Elements.Where(Function(e) e IsNot Nothing)
  373. Dim AniList As New List(Of AniData)
  374. Dim Delay As Integer = 0
  375. For Each Element In RealElements
  376. For Each Control As FrameworkElement In GetAllAnimControls(Element)
  377. If TypeOf Control Is MyExtraTextButton Then
  378. CType(Control, MyExtraTextButton).Show = False
  379. Else
  380. Control.IsHitTestVisible = False
  381. AniList.Add(AaOpacity(Control, -1, 70, Delay))
  382. AniList.Add(AaTranslateY(Control, -6, 70, Delay))
  383. Delay += 15
  384. End If
  385. Next
  386. Next
  387. '滚动条动画
  388. Dim Scroll As MyScrollBar = GetFirstScrollViewer(RealElements)
  389. If Scroll IsNot Nothing Then
  390. If TypeOf Scroll.RenderTransform IsNot TranslateTransform Then Scroll.RenderTransform = New TranslateTransform
  391. AniList.Add(AaTranslateX(Scroll, 10 - CType(Scroll.RenderTransform, TranslateTransform).X, 90, 0, New AniEaseInFluent))
  392. End If
  393. '结束
  394. AniList.Add(AaCode(
  395. Sub()
  396. For Each Element In RealElements
  397. Element.Visibility = Visibility.Collapsed
  398. Next
  399. PageOnExitAnimationFinished()
  400. End Sub,, True))
  401. AniStart(AniList, "PageRight PageChange " & PageUuid)
  402. End Sub
  403. ''' <summary>
  404. ''' 禁用页面切换动画的控件列表。
  405. ''' </summary>
  406. Public DisabledPageAnimControls As New List(Of FrameworkElement)
  407. ''' <summary>
  408. ''' 遍历获取所有需要生成动画的控件。
  409. ''' </summary>
  410. Friend Function GetAllAnimControls(Element As FrameworkElement, Optional IgnoreInvisibility As Boolean = False) As IEnumerable(Of FrameworkElement)
  411. Dim AllControls As New List(Of FrameworkElement)
  412. _GetAllAnimControls(Element, AllControls, IgnoreInvisibility)
  413. Return AllControls.Except(DisabledPageAnimControls)
  414. End Function
  415. Private Sub _GetAllAnimControls(Element As FrameworkElement, ByRef AllControls As List(Of FrameworkElement), IgnoreInvisibility As Boolean)
  416. If Not IgnoreInvisibility AndAlso Element.Visibility = Visibility.Collapsed Then Return
  417. If TypeOf Element Is MyCard OrElse TypeOf Element Is MyHint OrElse TypeOf Element Is MyExtraTextButton OrElse TypeOf Element Is TextBlock OrElse TypeOf Element Is MyTextButton Then
  418. AllControls.Add(Element)
  419. ElseIf TypeOf Element Is ContentControl Then
  420. Dim Content = CType(Element, ContentControl).Content
  421. If Content IsNot Nothing AndAlso TypeOf Content Is FrameworkElement Then _GetAllAnimControls(Content, AllControls, IgnoreInvisibility)
  422. ElseIf TypeOf Element Is Panel Then
  423. For Each Element2 In CType(Element, Panel).Children
  424. If TypeOf Element2 Is FrameworkElement Then _GetAllAnimControls(Element2, AllControls, IgnoreInvisibility)
  425. Next
  426. End If
  427. End Sub
  428. '查找列表中的第一个滚动条
  429. Private Function GetFirstScrollViewer(Elements As IEnumerable(Of FrameworkElement)) As MyScrollBar
  430. Dim Viewer As MyScrollViewer = Nothing
  431. For Each Element In Elements
  432. If TypeOf Element Is MyScrollViewer Then
  433. Viewer = Element
  434. GoTo FindViewer
  435. End If
  436. For Each Control In LogicalTreeHelper.GetChildren(Element)
  437. If TypeOf Control Is MyScrollViewer Then
  438. Viewer = Control
  439. GoTo FindViewer
  440. End If
  441. Next
  442. Next
  443. Return Nothing
  444. FindViewer:
  445. If Viewer.ComputedVerticalScrollBarVisibility <> Visibility.Visible Then Return Nothing
  446. Return Viewer.ScrollBar
  447. End Function
  448. #End Region
  449. End Class