网格不占用整页UWP

Question

这是我的UWP页面的XAML。

<Page
x:Class="App.AddComment"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:App"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" HorizontalContentAlignment="Stretch"  HorizontalAlignment="Stretch"
>
<Page.BottomAppBar>
    <CommandBar>
        <CommandBar.Content>
            <Grid/>
        </CommandBar.Content>
        <AppBarButton Icon="PostUpdate" Label="Post"/>
    </CommandBar>
</Page.BottomAppBar>

<StackPanel Margin="5,10,5,50" BorderBrush="Black" BorderThickness="3" Background="White" HorizontalAlignment="Stretch">
    <TextBlock Name="Title" HorizontalAlignment="Stretch" Margin="10" MinHeight="50" TextTrimming="CharacterEllipsis" TextWrapping="Wrap" Foreground="{StaticResource SystemControlBackgroundAccentBrush}" FontWeight="Normal" FontSize="20"/>
    <TextBox Name="CommentBox" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="10,20,10,20" AcceptsReturn="True" TextWrapping="Wrap" FontWeight="Thin" FontSize="18" VerticalContentAlignment="Stretch" Height="200" Header="Comment" PlaceholderText="Enter your comment here.."/>
</StackPanel>

但StackPanel并不占据整个页面（宽度）.. 即使我将Horizo​​ntalContentAlignment和HorizantalAlignment设置为Strech，它也不起作用.. 我甚至尝试使用网格替代StackPanel，但问题仍然存在。 Please see the image

Answer 1

包装页面内容的StackPanel似乎有一个保证金。

保证金会导致控件在控件外部添加一个间隙，使其具有如下所示：

您可能想要做的是删除不需要的边距，或将其更改为填充。

<StackPanel Padding="5,10,5,50" BorderBrush="Black" BorderThickness="3" Background="White" HorizontalAlignment="Stretch">
    <TextBlock Name="Title" HorizontalAlignment="Stretch" Margin="10" MinHeight="50" TextTrimming="CharacterEllipsis" TextWrapping="Wrap" Foreground="{StaticResource SystemControlBackgroundAccentBrush}" FontWeight="Normal" FontSize="20"/>
    <TextBox Name="CommentBox" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="10,20,10,20" AcceptsReturn="True" TextWrapping="Wrap" FontWeight="Thin" FontSize="18" VerticalContentAlignment="Stretch" Height="200" Header="Comment" PlaceholderText="Enter your comment here.."/>
</StackPanel>

填充会导致间隙出现在控件内部，如下所示：

这为您提供了相同的内容布局，但是它具有您希望StackPanel / Grid的边缘到边缘的外观。