我正在编写一款Windows 10 UWP应用程序,并想要将NavigationView与BackRequested事件处理程序结合使用来处理后退导航,然而“GoBack”不会更新选定的菜单项,这意味着当我使用后退按钮时,选定的菜单项不会改变。为了解决这个问题,我创建了一个丑陋的foreach循环,在后退导航时使用标记选择MenuItem。这种方法可行,但我想知道是否有更优雅的方式。
由于GoBack不触发ItemInvoked或SelectionChanged事件,所以我似乎无法使用它们。
MainPage.xaml
由于GoBack不触发ItemInvoked或SelectionChanged事件,所以我似乎无法使用它们。
MainPage.xaml
<NavigationView x:Name="NavView"
CompactModeThresholdWidth="1920" ExpandedModeThresholdWidth="1920"
ItemInvoked="NavView_ItemInvoked"
SelectionChanged="NavView_SelectionChanged"
Loaded="NavView_Loaded"
Canvas.ZIndex="0">
<NavigationView.MenuItems>
<NavigationViewItem x:Uid="HomeNavItem" Content="Home" Tag="home">
<NavigationViewItem.Icon>
<FontIcon Glyph=""/>
</NavigationViewItem.Icon>
</NavigationViewItem>
<NavigationViewItemSeparator/>
</NavigationView.MenuItems>
<NavigationView.HeaderTemplate>
<DataTemplate>
<Grid Margin="24,10,0,0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Style="{StaticResource TitleTextBlockStyle}"
FontSize="28"
VerticalAlignment="Center"
Text="Welcome"/>
</Grid>
</DataTemplate>
</NavigationView.HeaderTemplate>
<Frame x:Name="ContentFrame" Margin="24">
<Frame.ContentTransitions>
<TransitionCollection>
<NavigationThemeTransition/>
</TransitionCollection>
</Frame.ContentTransitions>
</Frame>
</NavigationView>
MainPage.xaml.cs片段:
public MainPage()
{
this.InitializeComponent();
// initial page for ContentFrame
ContentFrame.Navigate(typeof(HomePage));
ContentFrame.Navigated += MainFrame_Navigated;
SystemNavigationManager.GetForCurrentView().BackRequested += MainPage_BackRequested;
}
private void MainPage_BackRequested(object sender, BackRequestedEventArgs e)
{
string tag = null;
if (!ContentFrame.CanGoBack) return;
e.Handled = true;
ContentFrame.GoBack();
if (ContentFrame.SourcePageType == typeof(HomePage))
{
tag = "home";
}
foreach (var navViewMenuItem in NavView.MenuItems)
{
if (navViewMenuItem is NavigationViewItem item)
{
if (item.Tag.Equals(tag)) item.IsSelected = true;
}
}
}
private void MainFrame_Navigated(object sender, NavigationEventArgs e)
{
SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility = ((Frame) sender).CanGoBack
? AppViewBackButtonVisibility.Visible
: AppViewBackButtonVisibility.Collapsed;
}
if(args.IsSettingsInvoked){ //处理设置单击 } else {//在此处放置现有的github代码}
的else块中。 - Keven M