468 lines
22 KiB
VB.net
468 lines
22 KiB
VB.net
Public Class MyPageRight
|
||
Inherits AdornerDecorator
|
||
Public PageUuid As Integer = GetUuid()
|
||
|
||
'“返回顶部” 按钮检测的滚动区域
|
||
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）
|
||
Get
|
||
Return GetValue(PanScrollProperty)
|
||
End Get
|
||
Set(value As String)
|
||
SetValue(PanScrollProperty, value)
|
||
End Set
|
||
End Property
|
||
Private Shared ReadOnly PanScrollProperty =
|
||
DependencyProperty.Register("PanScroll", GetType(String), GetType(MyPageRight), New PropertyMetadata(Nothing))
|
||
|
||
'当前状态
|
||
Public Enum PageStates
|
||
Empty '默认状态，页面全空
|
||
LoaderWait '加载环初始等待
|
||
LoaderEnter '加载环进入动画
|
||
LoaderStayForce '加载环正常显示（强制等待）
|
||
LoaderStay '加载环正常显示
|
||
LoaderExit '加载环退出动画
|
||
ContentEnter '内容进入动画
|
||
ContentStay '内容正常显示
|
||
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
|
||
PageExit '切换页面导致的全部退出动画
|
||
End Enum
|
||
Private _PageState As PageStates = PageStates.Empty
|
||
Public Property PageState As PageStates
|
||
Get
|
||
Return _PageState
|
||
End Get
|
||
Set(value As PageStates)
|
||
If _PageState = value Then Return
|
||
_PageState = value
|
||
If ModeDebug Then Log("[UI] 页面状态切换为 " & GetStringFromEnum(value))
|
||
End Set
|
||
End Property
|
||
|
||
#Region "加载器"
|
||
|
||
Private PageLoader As LoaderBase
|
||
Private PageLoaderInputInvoke
|
||
Private PageLoaderUi As MyLoading
|
||
Private PanLoader As FrameworkElement
|
||
Private PanContent As FrameworkElement
|
||
Private PanAlways As FrameworkElement
|
||
Private PageLoaderAutoRun As Boolean
|
||
|
||
'初始化
|
||
''' <summary>
|
||
''' 表明页面存在需要在后台执行的加载器。
|
||
''' </summary>
|
||
''' <param name="LoaderUi">MyLoading 控件。</param>
|
||
''' <param name="PanLoader">MyLoading 控件对应的卡片。</param>
|
||
''' <param name="PanContent">加载结束后出现的内容容器。</param>
|
||
''' <param name="PanAlways">无论是否在加载总是要显示的容器。可以为 Nothing。</param>
|
||
''' <param name="RealLoader">在工作线程执行的加载器。</param>
|
||
''' <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>
|
||
Public Sub PageLoaderInit(LoaderUi As MyLoading, PanLoader As FrameworkElement, PanContent As FrameworkElement, PanAlways As FrameworkElement,
|
||
RealLoader As LoaderBase,
|
||
Optional FinishedInvoke As Action(Of LoaderBase) = Nothing, Optional InputInvoke As Func(Of Object) = Nothing,
|
||
Optional AutoRun As Boolean = True)
|
||
'初始化参数
|
||
Me.PanLoader = PanLoader
|
||
Me.PanContent = PanContent
|
||
Me.PanAlways = PanAlways
|
||
Me.PageLoader = RealLoader
|
||
Me.PageLoaderUi = LoaderUi
|
||
Me.PageLoaderInputInvoke = InputInvoke
|
||
Me.PageLoaderAutoRun = AutoRun
|
||
'添加结束 Invoke
|
||
If FinishedInvoke IsNot Nothing Then
|
||
AddHandler RealLoader.PreviewFinish,
|
||
Sub()
|
||
Do While PageState = MyPageRight.PageStates.PageExit OrElse PageState = MyPageRight.PageStates.ContentExit
|
||
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
|
||
Loop
|
||
RunInUiWait(Sub() FinishedInvoke(RealLoader))
|
||
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
|
||
End Sub
|
||
End If
|
||
AddHandler RealLoader.OnStateChangedUi, Sub(Loader As LoaderBase, NewState As LoadState, OldState As LoadState) RunInUi(Sub() PageLoaderState(Loader, NewState, OldState))
|
||
'隐藏 UI
|
||
PanLoader.Visibility = Visibility.Collapsed
|
||
PanContent.Visibility = Visibility.Collapsed
|
||
If PanAlways IsNot Nothing Then PanAlways.Visibility = Visibility.Collapsed
|
||
'初次运行加载器
|
||
If PageLoaderAutoRun Then
|
||
If PageLoader.GetType.Name.StartsWithF("LoaderTask") Then
|
||
PageLoader.Start(CType(PageLoader, Object).StartGetInput(Nothing, PageLoaderInputInvoke))
|
||
Else
|
||
Dim Input = Nothing
|
||
If PageLoaderInputInvoke IsNot Nothing Then Input = PageLoaderInputInvoke()
|
||
PageLoader.Start(Input)
|
||
End If
|
||
End If
|
||
If PageLoader.State = LoadState.Finished AndAlso FinishedInvoke IsNot Nothing Then
|
||
RunInUiWait(Sub() FinishedInvoke(RealLoader)) '加载器已提前完成，直接触发事件
|
||
End If
|
||
'设置加载环
|
||
PageLoaderUi.State = RealLoader
|
||
AddHandler PageLoaderUi.Click, Sub() If RealLoader.State = LoadState.Failed Then PageLoaderRestart() '点击重试事件
|
||
End Sub
|
||
'重试
|
||
Public Sub PageLoaderRestart(Optional Input As Object = Nothing, Optional IsForceRestart As Boolean = True) '由外部调用的重试
|
||
If Not PageLoaderAutoRun Then Return
|
||
If PageLoader.GetType.Name.StartsWithF("LoaderTask") Then
|
||
PageLoader.Start(CType(PageLoader, Object).StartGetInput(Input, PageLoaderInputInvoke), IsForceRestart:=IsForceRestart)
|
||
Else
|
||
If Input Is Nothing AndAlso PageLoaderInputInvoke IsNot Nothing Then Input = PageLoaderInputInvoke()
|
||
PageLoader.Start(Input, IsForceRestart:=IsForceRestart)
|
||
End If
|
||
End Sub
|
||
|
||
#End Region
|
||
|
||
#Region "事件"
|
||
|
||
'外部触发的事件
|
||
''' <summary>
|
||
''' 需要切换到当前页面，并且原本的 Loaded 事件已执行完成。
|
||
''' 需要根据加载器状态，从 Empty 切换到 ContentEnter、LoaderWait、LoaderEnter。
|
||
''' </summary>
|
||
Public Sub PageOnEnter()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnEnter")
|
||
RaiseEvent PageEnter()
|
||
Select Case PageState
|
||
Case PageStates.Empty
|
||
If PageLoader Is Nothing OrElse PageLoader.State = LoadState.Finished OrElse PageLoader.State = LoadState.Waiting OrElse PageLoader.State = LoadState.Aborted Then
|
||
'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
|
||
PageState = PageStates.ContentEnter
|
||
TriggerEnterAnimation(PanAlways, If(PanContent, Child))
|
||
ElseIf PageLoader.State = LoadState.Loading Then
|
||
PageState = PageStates.LoaderWait
|
||
AniStart(AaCode(AddressOf PageOnLoaderWaitFinished, 200), "PageRight PageChange " & PageUuid)
|
||
Else 'PageLoader.State = LoadState.Failed
|
||
PageState = PageStates.LoaderEnter
|
||
TriggerEnterAnimation(PanAlways, PanLoader)
|
||
End If
|
||
Case PageStates.ContentExit
|
||
'和上面的一样，但是不管 PanAlways
|
||
If PageLoader Is Nothing OrElse PageLoader.State = LoadState.Finished OrElse PageLoader.State = LoadState.Waiting OrElse PageLoader.State = LoadState.Aborted Then
|
||
PageState = PageStates.ContentEnter
|
||
TriggerEnterAnimation(If(PanContent, Child))
|
||
ElseIf PageLoader.State = LoadState.Loading Then
|
||
PageState = PageStates.LoaderWait
|
||
AniStart(AaCode(AddressOf PageOnLoaderWaitFinished, 200), "PageRight PageChange " & PageUuid)
|
||
Else 'PageLoader.State = LoadState.Failed
|
||
PageState = PageStates.LoaderEnter
|
||
TriggerEnterAnimation(PanLoader)
|
||
End If
|
||
Case PageStates.ContentEnter
|
||
'重复调用 PageOnEnter，直接忽略
|
||
Case Else
|
||
Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnEnter 事件。")
|
||
End Select
|
||
End Sub
|
||
Public Event PageEnter()
|
||
''' <summary>
|
||
''' 需要切换到其他页面。
|
||
''' 需要立即切换至 PageExit 或 Empty。
|
||
''' </summary>
|
||
Public Sub PageOnExit()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnExit")
|
||
RaiseEvent PageExit()
|
||
Select Case PageState
|
||
Case PageStates.ContentEnter, PageStates.ContentStay
|
||
PageState = PageStates.PageExit
|
||
TriggerExitAnimation(PanAlways, If(PanContent, Child))
|
||
Case PageStates.LoaderEnter, PageStates.LoaderStayForce, PageStates.LoaderStay
|
||
PageState = PageStates.PageExit
|
||
TriggerExitAnimation(PanAlways, PanLoader)
|
||
Case PageStates.LoaderWait
|
||
PageState = PageStates.PageExit
|
||
TriggerExitAnimation(PanAlways)
|
||
Case PageStates.LoaderExit, PageStates.ContentExit
|
||
PageState = PageStates.PageExit
|
||
If PanAlways IsNot Nothing Then TriggerExitAnimation(PanAlways, If(PanContent, Child))
|
||
Case PageStates.PageExit, PageStates.Empty
|
||
End Select
|
||
End Sub
|
||
Public Event PageExit()
|
||
''' <summary>
|
||
''' 即将切换到其他页面，需要强制完成页面状态清理。
|
||
''' 需要立即切换至 Empty。
|
||
''' </summary>
|
||
Public Sub PageOnForceExit()
|
||
If PageState = PageStates.Empty Then Return
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnForceExit")
|
||
PageState = PageStates.Empty
|
||
AniStop("PageRight PageChange " & PageUuid)
|
||
'由于动画会被强制中止，所以需要手动进行隐藏
|
||
If PageLoader Is Nothing Then
|
||
Child.Visibility = Visibility.Collapsed
|
||
Else
|
||
PanContent.Visibility = Visibility.Collapsed
|
||
PanLoader.Visibility = Visibility.Collapsed
|
||
If PanAlways IsNot Nothing Then PanAlways.Visibility = Visibility.Collapsed
|
||
End If
|
||
End Sub
|
||
''' <summary>
|
||
''' PanContent 中的子页面改变，需要让当前内容退出，再显示新的内容。
|
||
''' 需要在 PageEnter 事件确认要显示的子页面有哪些。
|
||
''' </summary>
|
||
Public Sub PageOnContentExit()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnContentExit")
|
||
If PageLoader IsNot Nothing AndAlso PageLoader.State = LoadState.Loading Then
|
||
'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
|
||
Throw New Exception("在调用 PageOnContentExit 时，加载器不能为 Loading 状态")
|
||
End If
|
||
Select Case PageState
|
||
Case PageStates.ContentEnter, PageStates.ContentStay
|
||
PageState = PageStates.ContentExit
|
||
TriggerExitAnimation(PanContent)
|
||
Case PageStates.LoaderExit
|
||
PageState = PageStates.ContentExit
|
||
Case PageStates.LoaderEnter, PageStates.LoaderStayForce, PageStates.LoaderStay
|
||
PageState = PageStates.ContentExit
|
||
TriggerExitAnimation(PanLoader)
|
||
Case PageStates.LoaderWait
|
||
PageOnEnter()
|
||
Case PageStates.Empty
|
||
'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()
|
||
'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
|
||
If IsLoaded Then PageOnEnter()
|
||
End Select
|
||
End Sub
|
||
|
||
'内部触发的事件
|
||
''' <summary>
|
||
''' 逐个进入动画已执行完成。
|
||
''' 需要根据目前状态，从 ContentEnter 切换到 ContentStay，或从 LoaderEnter 切换到 LoaderStayForce。
|
||
''' </summary>
|
||
Private Sub PageOnEnterAnimationFinished()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnEnterAnimationFinished")
|
||
Select Case PageState
|
||
Case PageStates.ContentEnter
|
||
PageState = PageStates.ContentStay
|
||
Case PageStates.LoaderEnter
|
||
PageState = PageStates.LoaderStayForce
|
||
AniStart(AaCode(AddressOf PageOnLoaderStayFinished, 400), "PageRight PageChange " & PageUuid)
|
||
Case Else
|
||
Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnEnterAnimationFinished 事件。")
|
||
End Select
|
||
End Sub
|
||
''' <summary>
|
||
''' 逐个退出动画已执行完成。
|
||
''' 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。
|
||
''' </summary>
|
||
Private Sub PageOnExitAnimationFinished()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnExitAnimationFinished")
|
||
Select Case PageState
|
||
Case PageStates.PageExit
|
||
PageState = PageStates.Empty
|
||
Case PageStates.ContentExit
|
||
PageOnEnter()
|
||
Case PageStates.LoaderExit
|
||
PageState = PageStates.ContentEnter
|
||
TriggerEnterAnimation(PanContent)
|
||
Case Else
|
||
Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnExitAnimationFinished 事件。")
|
||
End Select
|
||
End Sub
|
||
''' <summary>
|
||
''' 加载环进入等待已结束。
|
||
''' 需要从 LoaderWait 切换到 LoaderEnter。
|
||
''' </summary>
|
||
Private Sub PageOnLoaderWaitFinished()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnLoaderWaitFinished")
|
||
Select Case PageState
|
||
Case PageStates.LoaderWait
|
||
PageState = PageStates.LoaderEnter
|
||
If PanAlways IsNot Nothing AndAlso PanAlways.Visibility = Visibility.Collapsed Then
|
||
TriggerEnterAnimation(PanAlways, PanLoader)
|
||
Else
|
||
TriggerEnterAnimation(PanLoader)
|
||
End If
|
||
Case Else
|
||
Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnLoaderWaitFinished 事件。")
|
||
End Select
|
||
End Sub
|
||
''' <summary>
|
||
''' 加载环展示等待已结束。
|
||
''' 需要从 LoaderStayForce 切换到 LoaderStay 或 LoaderExit。
|
||
''' </summary>
|
||
Private Sub PageOnLoaderStayFinished()
|
||
If ModeDebug Then Log("[UI] 已触发 PageOnLoaderStayFinished")
|
||
Select Case PageState
|
||
Case PageStates.LoaderStayForce
|
||
If PageLoader.State = LoadState.Finished Then
|
||
PageState = PageStates.LoaderExit
|
||
TriggerExitAnimation(PanLoader)
|
||
Else
|
||
PageState = PageStates.LoaderStay
|
||
End If
|
||
Case Else
|
||
Throw New Exception("在状态为 " & GetStringFromEnum(PageState) & " 时触发了 PageOnLoaderWaitFinished 事件。")
|
||
End Select
|
||
End Sub
|
||
|
||
''' <summary>
|
||
''' 全局加载状态已改变。
|
||
''' </summary>
|
||
Private Sub PageLoaderState(sender As Object, NewState As LoadState, OldState As LoadState)
|
||
Select Case NewState
|
||
Case LoadState.Failed, LoadState.Loading
|
||
If OldState = LoadState.Failed OrElse OldState = LoadState.Loading Then Return
|
||
If ModeDebug Then Log("[UI] 已触发 PageLoaderState (Start/Refresh)")
|
||
'（重新）开始运行
|
||
'需要从部分状态切换到 ReloadExit
|
||
Select Case PageState
|
||
Case PageStates.ContentEnter, PageStates.ContentStay
|
||
PageState = PageStates.ContentExit
|
||
TriggerExitAnimation(PanContent)
|
||
Case PageStates.LoaderExit
|
||
PageState = PageStates.ContentExit
|
||
End Select
|
||
Case LoadState.Finished, LoadState.Aborted, LoadState.Waiting
|
||
If Not (OldState = LoadState.Failed OrElse OldState = LoadState.Loading) Then Return
|
||
If ModeDebug Then Log("[UI] 已触发 PageLoaderState (Stop/Abort)")
|
||
'运行结束
|
||
'需要从 LoaderWait 切换到 ContentEnter，或从 LoaderStay 切换到 LoaderExit
|
||
Select Case PageState
|
||
Case PageStates.LoaderWait
|
||
PageState = PageStates.ContentEnter
|
||
If PanAlways IsNot Nothing AndAlso PanAlways.Visibility = Visibility.Collapsed Then
|
||
TriggerEnterAnimation(PanAlways, PanContent)
|
||
Else
|
||
TriggerEnterAnimation(PanContent)
|
||
End If
|
||
Case PageStates.LoaderStay
|
||
PageState = PageStates.LoaderExit
|
||
TriggerExitAnimation(PanLoader)
|
||
End Select
|
||
End Select
|
||
End Sub
|
||
|
||
#End Region
|
||
|
||
#Region "动画"
|
||
|
||
'逐个进入动画
|
||
Public Sub TriggerEnterAnimation(ParamArray Elements As FrameworkElement())
|
||
Dim RealElements = Elements.Where(Function(e) e IsNot Nothing)
|
||
For Each Element In RealElements
|
||
Element.Visibility = Visibility.Visible '页面均处于默认的隐藏状态
|
||
Next
|
||
Dim AniList As New List(Of AniData)
|
||
Dim Delay As Integer = 0
|
||
'基础动画
|
||
For Each Element In RealElements
|
||
For Each Control As FrameworkElement In GetAllAnimControls(Element, True)
|
||
'还原被隐藏的卡片的消失动画
|
||
Control.IsHitTestVisible = True
|
||
If Control.RenderTransform IsNot Nothing AndAlso TypeOf Control.RenderTransform Is TranslateTransform Then Control.RenderTransform = Nothing
|
||
Next
|
||
For Each Control As FrameworkElement In GetAllAnimControls(Element)
|
||
If TypeOf Control Is MyExtraTextButton Then
|
||
CType(Control, MyExtraTextButton).Show = True
|
||
Else
|
||
Control.Opacity = 0
|
||
Control.RenderTransform = New TranslateTransform(0, -16)
|
||
AniList.Add(AaOpacity(Control, 1, 100, Delay, New AniEaseOutFluent(AniEasePower.Weak)))
|
||
AniList.Add(AaTranslateY(Control, 5, 250, Delay, New AniEaseOutFluent))
|
||
AniList.Add(AaTranslateY(Control, 11, 350, Delay, New AniEaseOutBack))
|
||
Delay += 25
|
||
End If
|
||
Next
|
||
Next
|
||
'滚动条动画
|
||
Dim Scroll As MyScrollBar = GetFirstScrollViewer(RealElements)
|
||
If Scroll IsNot Nothing Then
|
||
If TypeOf Scroll.RenderTransform IsNot TranslateTransform Then Scroll.RenderTransform = New TranslateTransform(10, 0)
|
||
AniList.Add(AaTranslateX(Scroll, -CType(Scroll.RenderTransform, TranslateTransform).X, 350, 0, New AniEaseOutFluent))
|
||
End If
|
||
'结束
|
||
AniList.Add(AaCode(Sub() PageOnEnterAnimationFinished(),, True))
|
||
AniStart(AniList, "PageRight PageChange " & PageUuid)
|
||
End Sub
|
||
|
||
'逐个退出动画
|
||
Public Sub TriggerExitAnimation(ParamArray Elements As FrameworkElement())
|
||
Dim RealElements = Elements.Where(Function(e) e IsNot Nothing)
|
||
Dim AniList As New List(Of AniData)
|
||
Dim Delay As Integer = 0
|
||
For Each Element In RealElements
|
||
For Each Control As FrameworkElement In GetAllAnimControls(Element)
|
||
If TypeOf Control Is MyExtraTextButton Then
|
||
CType(Control, MyExtraTextButton).Show = False
|
||
Else
|
||
Control.IsHitTestVisible = False
|
||
AniList.Add(AaOpacity(Control, -1, 70, Delay))
|
||
AniList.Add(AaTranslateY(Control, -6, 70, Delay))
|
||
Delay += 15
|
||
End If
|
||
Next
|
||
Next
|
||
'滚动条动画
|
||
Dim Scroll As MyScrollBar = GetFirstScrollViewer(RealElements)
|
||
If Scroll IsNot Nothing Then
|
||
If TypeOf Scroll.RenderTransform IsNot TranslateTransform Then Scroll.RenderTransform = New TranslateTransform
|
||
AniList.Add(AaTranslateX(Scroll, 10 - CType(Scroll.RenderTransform, TranslateTransform).X, 90, 0, New AniEaseInFluent))
|
||
End If
|
||
'结束
|
||
AniList.Add(AaCode(
|
||
Sub()
|
||
For Each Element In RealElements
|
||
Element.Visibility = Visibility.Collapsed
|
||
Next
|
||
PageOnExitAnimationFinished()
|
||
End Sub,, True))
|
||
AniStart(AniList, "PageRight PageChange " & PageUuid)
|
||
End Sub
|
||
|
||
''' <summary>
|
||
''' 禁用页面切换动画的控件列表。
|
||
''' </summary>
|
||
Public DisabledPageAnimControls As New List(Of FrameworkElement)
|
||
''' <summary>
|
||
''' 遍历获取所有需要生成动画的控件。
|
||
''' </summary>
|
||
Friend Function GetAllAnimControls(Element As FrameworkElement, Optional IgnoreInvisibility As Boolean = False) As IEnumerable(Of FrameworkElement)
|
||
Dim AllControls As New List(Of FrameworkElement)
|
||
_GetAllAnimControls(Element, AllControls, IgnoreInvisibility)
|
||
Return AllControls.Except(DisabledPageAnimControls)
|
||
End Function
|
||
Private Sub _GetAllAnimControls(Element As FrameworkElement, ByRef AllControls As List(Of FrameworkElement), IgnoreInvisibility As Boolean)
|
||
If Not IgnoreInvisibility AndAlso Element.Visibility = Visibility.Collapsed Then Return
|
||
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
|
||
AllControls.Add(Element)
|
||
ElseIf TypeOf Element Is ContentControl Then
|
||
Dim Content = CType(Element, ContentControl).Content
|
||
If Content IsNot Nothing AndAlso TypeOf Content Is FrameworkElement Then _GetAllAnimControls(Content, AllControls, IgnoreInvisibility)
|
||
ElseIf TypeOf Element Is Panel Then
|
||
For Each Element2 In CType(Element, Panel).Children
|
||
If TypeOf Element2 Is FrameworkElement Then _GetAllAnimControls(Element2, AllControls, IgnoreInvisibility)
|
||
Next
|
||
End If
|
||
End Sub
|
||
|
||
'查找列表中的第一个滚动条
|
||
Private Function GetFirstScrollViewer(Elements As IEnumerable(Of FrameworkElement)) As MyScrollBar
|
||
Dim Viewer As MyScrollViewer = Nothing
|
||
For Each Element In Elements
|
||
If TypeOf Element Is MyScrollViewer Then
|
||
Viewer = Element
|
||
GoTo FindViewer
|
||
End If
|
||
For Each Control In LogicalTreeHelper.GetChildren(Element)
|
||
If TypeOf Control Is MyScrollViewer Then
|
||
Viewer = Control
|
||
GoTo FindViewer
|
||
End If
|
||
Next
|
||
Next
|
||
Return Nothing
|
||
FindViewer:
|
||
If Viewer.ComputedVerticalScrollBarVisibility <> Visibility.Visible Then Return Nothing
|
||
Return Viewer.ScrollBar
|
||
End Function
|
||
|
||
#End Region
|
||
|
||
End Class
|