Question

在WPF应用程序中，我们有时需要创建一个包含框架内页面的新选项卡。

页面打开后（初始化一次），它似乎仍然保留在导航历史记录中，并尝试加载当时可能不相关的数据。

我尝试过无数种方法，包括NavigationService.RemoveBackEntry，但它仍然存在： - （

这是标签/页面打开方式的示例

 Private Sub CashFlow_Edit(sender As Object, e As RoutedEventArgs)
    Try
        Dim DGV As DGVx = ReportsCashFlow_Grid.FindName("CashFlow_DGV")
        e.Handled = True
        IsNewRecord = False

        If DGV.SelectedItems.Count = 1 Then
            Dim row As System.Data.DataRowView = DGV.SelectedItems(0)
            Form_ID = row("ID")
            Dim vName As String = row("Name")
            Dim vTab As STC_Tabx = Application.Current.MainWindow.FindName(TabName)
            Dim TabControl As STCx = Application.Current.MainWindow.FindName("AccountingReports_TabControl")
            If Not vTab Is Nothing Then
                vTab.Close()
            End If
            Dim MCFrame As New Frame
            Dim MCTab As New STC_Tabx
            With MCTab
                .Name = TabName
                .Header = " " & vName & " "
                .ImageSource = ReturnImageAsString("Edit.png", 16)
                .CloseButtonVisibility = DevComponents.WpfEditors.eTabCloseButtonVisibility.Visible
                .TabToolTip = "View or edit the " & vName & " template"
                .Content = MCFrame
            End With
            RemoveHandler MCTab.Closing, AddressOf TabControl_TabClosing
            AddHandler MCTab.Closing, AddressOf TabControl_TabClosing

            Dim vGrid As Grid = Application.Current.MainWindow.FindName("MainGrid_Accounting")
            RegisterControl(vGrid, MCTab)
            TabControl.Items.Add(MCTab)
            Dim MCPage As New ReportCashFlow_Page
            MCFrame.NavigationService.Navigate(MCPage)
            LoadedTabs(TabName)
            MCTab.IsSelected = True


        End If

    Catch ex As Exception
        EmailError(ex)
    End Try
End Sub

Answer 1

要删除所有后退条目，请执行以下操作：

if (runner->next)
     runner->next->prev = runner;

Answer 2

这不是我想要的干净的代码，但它可以工作 - 创建一个全局布尔 - 当打开选项卡/页面的子被调用时，它被设置为true，加载事件只会运行加载代码是真的 - 最后它被设置为假。

Private Sub ReportCashFlow_Page_Loaded(sender As Object, e As RoutedEventArgs) Handles Me.Loaded
    Try


        If IsNewTab = False Then
            Exit Sub
        End If
 'Run all the loading code here


  Catch ex As Exception
        EmailError(ex)
    Finally
        IsNewTab = False
        Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background, CType(Sub() CashFlow_LoadBudget(), SendOrPostCallback), Nothing)
        Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background, CType(Sub() ToggleReserve(), SendOrPostCallback), Nothing)
    End Try
End Sub

WPF - 在卸载运行后销毁页面

2 个答案: