在我的 UWP 中,我试图在框架中心打开一个 MenuFlyout。
我怎样才能把它放在中心?
我试过这段代码,但它在框架顶部设置了弹出按钮。
private void ListView_ItemClick(object sender,ItemClickEventArgs e) {
var m = new MenuFlyout();
var t = new MenuFlyoutItem() { Text = "SomeTxt"};
m.Items.Add(t);
m.ShowAt((FrameworkElement)Frame);
}
甚至尝试添加 m.Placement = Windows.UI.Xaml.Controls.Primitives.FlyoutPlacementMode.Center;
但 FlyoutPlacementMode 枚举不包含 Center
.
最佳答案
不幸的是没有 Center
FlyoutPlacementMode
中的值因此您需要编写更多代码来解决问题。
思路是先设置FlyoutPlacementMode
至 Full
, 然后我们改变 Style
而不是让内容拉伸(stretch)到填满整个页面的 MenuFlyoutPresenter
使其内容水平和垂直居中。
所以我所做的是使用 Blend 生成以下默认样式并将其放置在 Page.Resources
中,然后我指定了 HorizontalAlignment="Center" VerticalAlignment="Center"
在根上 Grid
以使内容居中。
<Page.Resources>
<Style x:Key="CenteredMenuFlyoutPresenterStyle" TargetType="MenuFlyoutPresenter">
<Setter Property="Background" Value="{ThemeResource SystemControlBackgroundChromeMediumLowBrush}" />
<Setter Property="BorderBrush" Value="{ThemeResource SystemControlForegroundChromeHighBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource FlyoutBorderThemeThickness}" />
<Setter Property="Padding" Value="{ThemeResource MenuFlyoutPresenterThemePadding}" />
<Setter Property="ScrollViewer.HorizontalScrollMode" Value="Disabled" />
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
<Setter Property="ScrollViewer.VerticalScrollMode" Value="Auto" />
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
<Setter Property="ScrollViewer.IsHorizontalRailEnabled" Value="False" />
<Setter Property="ScrollViewer.IsVerticalRailEnabled" Value="False" />
<Setter Property="ScrollViewer.ZoomMode" Value="Disabled" />
<Setter Property="MinWidth" Value="{ThemeResource FlyoutThemeMinWidth}" />
<Setter Property="MaxWidth" Value="{ThemeResource FlyoutThemeMaxWidth}" />
<Setter Property="MinHeight" Value="{ThemeResource MenuFlyoutThemeMinHeight}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="MenuFlyoutPresenter">
<Grid Background="{TemplateBinding Background}" HorizontalAlignment="Center" VerticalAlignment="Center">
<ScrollViewer x:Name="MenuFlyoutPresenterScrollViewer" AutomationProperties.AccessibilityView="Raw" HorizontalScrollMode="{TemplateBinding ScrollViewer.HorizontalScrollMode}" HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}" IsHorizontalRailEnabled="{TemplateBinding ScrollViewer.IsHorizontalRailEnabled}" IsVerticalRailEnabled="{TemplateBinding ScrollViewer.IsVerticalRailEnabled}" Margin="{TemplateBinding BorderThickness}" Padding="{TemplateBinding Padding}" VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}" VerticalScrollMode="{TemplateBinding ScrollViewer.VerticalScrollMode}" ZoomMode="{TemplateBinding ScrollViewer.ZoomMode}">
<ItemsPresenter />
</ScrollViewer>
<Border x:Name="MenuFlyoutPresenterBorder" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
然后简单地将样式应用到 MenuFlyout
像这样 -
var m = new MenuFlyout
{
Placement = FlyoutPlacementMode.Full,
MenuFlyoutPresenterStyle = (Style)this.Resources["CenteredMenuFlyoutPresenterStyle"]
};
var t = new MenuFlyoutItem() { Text = "SomeTxt" };
m.Items.Add(t);
m.ShowAt((FrameworkElement)sender);
关于c# - 页面中心的 MenuFlyout,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/32209809/