我看到了很多关于移除后台堆栈的答案。
但是如何删除前向堆栈？
又名，导航 A，到 B，到 C
A -> B -> C
然后我从 C 导航回 B（表单已保存，C 已关闭NavigationService.GoBack();）
B <- C
我现在应该不能使用前进按钮导航回 C。但不知道如何实现这一点。以某种方式将其从堆栈中删除是最有意义的。
问问题
469 次
1 回答
0
我知道这个问题是很久以前发布的，但最近我偶然发现了类似的问题，这就是我为我的案例解决的方法。我希望它会帮助某人。
要求
用户应该能够返回到之前访问过的页面，但一旦按下后退按钮就不能前进。
我的方法
Frame创建一个派生自并添加两个附加 DP的自定义控件AllowForwardNavigation，AllowBackNavigation以便我可以控制是否要允许上一个/下一个导航。
MyFrame.xaml.cs
public partial class MyFrame : Frame
{
#region Dependency Properties
public bool AllowForwardNavigation
{
get { return (bool)GetValue(AllowForwardNavigationProperty); }
set { SetValue(AllowForwardNavigationProperty, value); }
}
public static readonly DependencyProperty AllowForwardNavigationProperty =
DependencyProperty.Register(nameof(AllowForwardNavigation), typeof(bool), typeof(MyFrame), new PropertyMetadata(true));
public bool AllowBackNavigation
{
get { return (bool)GetValue(AllowBackNavigationProperty); }
set { SetValue(AllowBackNavigationProperty, value); }
}
public static readonly DependencyProperty AllowBackNavigationProperty =
DependencyProperty.Register(nameof(AllowBackNavigation), typeof(bool), typeof(MyFrame), new PropertyMetadata(true));
#endregion
public MyFrame()
{
InitializeComponent();
JournalOwnership = JournalOwnership.OwnsJournal;
// find existing bindings
var existingBindings = CommandBindings.OfType<CommandBinding>()
.Where(x => x.Command == NavigationCommands.BrowseForward
|| x.Command == NavigationCommands.BrowseBack)
.ToArray();
// remove existing bindings
foreach (var binding in existingBindings)
CommandBindings.Remove(binding);
// add new binding
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseForward, OnGoForward, OnQueryGoForward));
CommandBindings.Add(new CommandBinding(NavigationCommands.BrowseBack, OnGoBack, OnQueryGoBack));
// override default navigation behavior
NavigationService.Navigating += NavigationService_Navigating;
}
private void NavigationService_Navigating(Object sender, NavigatingCancelEventArgs e)
{
switch (e.NavigationMode)
{
case NavigationMode.Forward:
e.Cancel = !AllowForwardNavigation;
break;
case NavigationMode.Back:
e.Cancel = !AllowBackNavigation;
break;
}
}
#region Command methods
private void OnGoForward(Object sender, ExecutedRoutedEventArgs e)
{
e.Handled = true;
if (AllowForwardNavigation && NavigationService.CanGoForward)
NavigationService.GoForward();
}
private void OnQueryGoForward(Object sender, CanExecuteRoutedEventArgs e)
{
e.Handled = true;
e.CanExecute = AllowForwardNavigation && NavigationService.CanGoForward;
}
private void OnGoBack(Object sender, ExecutedRoutedEventArgs e)
{
e.Handled = true;
if (AllowBackNavigation && NavigationService.CanGoBack)
NavigationService.GoBack();
}
private void OnQueryGoBack(Object sender, CanExecuteRoutedEventArgs e)
{
e.Handled = true;
e.CanExecute = AllowBackNavigation && NavigationService.CanGoBack;
}
#endregion
}
MyFrame.xaml
<Style x:Key="NavigationWindowBackButtonStyle" TargetType="{x:Type Button}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="Command" Value="NavigationCommands.BrowseBack"/>
<Setter Property="Focusable" Value="false"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid Background="Transparent" Height="24" Width="24">
<Ellipse x:Name="Circle" Fill="{StaticResource NavigationWindowNavigationButtonFillEnabled}" Stroke="{StaticResource NavigationWindowNavigationButtonStrokeEnabled}" StrokeThickness="1"/>
<Path x:Name="Arrow" Data="M0.37,7.69 L5.74,14.20 A1.5,1.5,0,1,0,10.26,12.27 L8.42,10.42 14.90,10.39 A1.5,1.5,0,1,0,14.92,5.87 L8.44,5.90 10.31,4.03 A1.5,1.5,0,1,0,5.79,1.77 z" Fill="{StaticResource NavigationWindowNavigationArrowFill}" HorizontalAlignment="Center" Stroke="{StaticResource NavigationWindowNavigationArrowStrokeEnabled}" StrokeThickness="0.75" VerticalAlignment="Center"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillDisabled}"/>
<Setter Property="Stroke" TargetName="Circle" Value="#B5BACE"/>
<Setter Property="Stroke" TargetName="Arrow" Value="#B0B5BACE"/>
<Setter Property="Fill" TargetName="Arrow" Value="#D0FFFFFF"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillHover}"/>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillPressed}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="NavigationWindowForwardButtonStyle" TargetType="{x:Type Button}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="Command" Value="NavigationCommands.BrowseForward"/>
<Setter Property="Focusable" Value="false"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid Background="Transparent" Height="24" Width="24">
<Ellipse x:Name="Circle" Grid.Column="0" Fill="{StaticResource NavigationWindowNavigationButtonFillEnabled}" Stroke="{StaticResource NavigationWindowNavigationButtonStrokeEnabled}" StrokeThickness="1"/>
<Path x:Name="Arrow" Grid.Column="0" Data="M0.37,7.69 L5.74,14.20 A1.5,1.5,0,1,0,10.26,12.27 L8.42,10.42 14.90,10.39 A1.5,1.5,0,1,0,14.92,5.87 L8.44,5.90 10.31,4.03 A1.5,1.5,0,1,0,5.79,1.77 z" Fill="{StaticResource NavigationWindowNavigationArrowFill}" HorizontalAlignment="Center" RenderTransformOrigin="0.5,0" Stroke="{StaticResource NavigationWindowNavigationArrowStrokeEnabled}" StrokeThickness="0.75" VerticalAlignment="Center">
<Path.RenderTransform>
<ScaleTransform ScaleX="-1"/>
</Path.RenderTransform>
</Path>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillDisabled}"/>
<Setter Property="Stroke" TargetName="Circle" Value="#B5BACE"/>
<Setter Property="Stroke" TargetName="Arrow" Value="#B0B5BACE"/>
<Setter Property="Fill" TargetName="Arrow" Value="#D0FFFFFF"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillHover}"/>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Fill" TargetName="Circle" Value="{StaticResource NavigationWindowNavigationButtonFillPressed}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>
</Frame.Resources>
<Frame.Template>
<ControlTemplate TargetType="Frame">
<DockPanel Margin="7">
<StackPanel Visibility="{TemplateBinding NavigationUIVisibility}" Margin="0" Orientation="Horizontal"
DockPanel.Dock="Top">
<Button Style="{StaticResource NavigationWindowBackButtonStyle}"
Command="NavigationCommands.BrowseBack"
Content="M 4 0 L 0 4 L 4 8 Z"
Margin="2.7,0,1.3,0" />
<Button Style="{StaticResource NavigationWindowForwardButtonStyle}"
Command="NavigationCommands.BrowseForward"
Content="M 4 0 L 0 4 L 4 8 Z" Margin="1.3,0,0,0" />
</StackPanel>
<Border>
<ContentPresenter />
</Border>
</DockPanel>
</ControlTemplate>
</Frame.Template>
</Frame>
用法
<local:MyFrame x:Name="_mainFrame" NavigationUIVisibility="Visible"
AllowForwardNavigation="False" />
于 2018-08-21T18:20:07.723 回答