我正在我的应用程序中设置打印功能。为此，我有两个页面：PrintPage和OverflowPage. 两者都继承自我的自定义摘要Page，PrintablePage. 以下是它们的 XAML 布局：
PrintPage.xaml
<RelativePanel>
<RelativePanel x:Name="Header"
BorderBrush="Gray"
BorderThickness="0 0 0 1"
Margin="48 48 48 12"
Padding="0 0 0 6"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.AlignTopWithPanel="True">
<TextBlock x:Name="RouteTextBlock"
Style="{ThemeResource TitleTextBlockStyle}"
Text="{x:Bind Route, Mode=OneWay}" />
<TextBlock x:Name="StaffTextBlock"
Foreground="{ThemeResource ApplicationSecondaryForegroundThemeBrush}"
Margin="0 6 0 0"
RelativePanel.Below="RouteTextBlock"
Text="{x:Bind Staff, Mode=OneWay}"
TextWrapping="Wrap" />
<TextBlock x:Name="Legend"
FontSize="14"
Foreground="{ThemeResource ApplicationSecondaryForegroundThemeBrush}"
Margin="0 12 0 24"
RelativePanel.Below="StaffTextBlock">
<Run FontFamily="/Assets/Fonts/Kimble.ttf#Kimble-UWP"
FontSize="16"
Text="" /> = Parent must be present for pickup
</TextBlock>
<Grid x:Name="DataHeader"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.Below="Legend">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="24" />
<ColumnDefinition Width="48" />
<ColumnDefinition />
<ColumnDefinition />
<ColumnDefinition Width="60" />
</Grid.ColumnDefinitions>
<TextBlock x:Name="NameHeader"
FontWeight="SemiBold"
Grid.Column="2"
Grid.Row="2"
Text="Name" />
<TextBlock x:Name="AddressHeader"
FontWeight="SemiBold"
Grid.Column="3"
Grid.Row="2"
Text="Address" />
<TextBlock x:Name="AgeHeader"
FontWeight="SemiBold"
Grid.Column="4"
Grid.Row="2"
HorizontalTextAlignment="Right"
Text="Age" />
</Grid>
</RelativePanel>
<RichTextBlock x:Name="MainContentTextBlock"
HorizontalAlignment="Stretch"
RelativePanel.Above="InstructionsTextBlock"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.Below="Header" />
<TextBlock x:Name="InstructionsTextBlock"
Foreground="{ThemeResource ApplicationSecondaryForegroundThemeBrush}"
Margin="0 0 0 24"
RelativePanel.AlignHorizontalCenterWithPanel="True"
RelativePanel.AlignBottomWithPanel="True"
Text="Please fill out this form and return it at the end of the night" />
</RelativePanel>
OverflowPage.xaml
<RelativePanel Margin="0 0 0 12">
<Grid x:Name="Header"
BorderBrush="Gray"
BorderThickness="0 0 0 1"
Margin="48 48 48 12"
Padding="0 0 0 6"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.AlignTopWithPanel="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="24" />
<ColumnDefinition Width="48" />
<ColumnDefinition />
<ColumnDefinition />
<ColumnDefinition Width="60" />
</Grid.ColumnDefinitions>
<TextBlock x:Name="NameHeader"
FontWeight="SemiBold"
Grid.Column="2"
Grid.Row="2"
Text="Name" />
<TextBlock x:Name="AddressHeader"
FontWeight="SemiBold"
Grid.Column="3"
Grid.Row="2"
Text="Address" />
<TextBlock x:Name="AgeHeader"
FontWeight="SemiBold"
Grid.Column="4"
Grid.Row="2"
HorizontalTextAlignment="Right"
Text="Age" />
</Grid>
<RichTextBlockOverflow x:Name="OverflowBlock"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.AlignRightWithPanel="True"
RelativePanel.Below="Header" />
</RelativePanel>
在PrintPage我的构造函数中呈现项目列表：
var pageWidthBinding = new Binding
{
FallbackValue = 0,
TargetNullValue = 0,
Source = this,
Path = new PropertyPath("PageWidth"),
Mode = BindingMode.OneWay
};
foreach (var child in Children)
{
var uiContainer = new InlineUIContainer();
var contentPresenter = new ContentPresenter
{
Content = child,
ContentTemplate = ChildItemTemplate
};
contentPresenter.SetBinding(WidthProperty, pageWidthBinding);
uiContainer.Child = contentPresenter;
var paragraph = new Paragraph { LineHeight = 18, Margin = new Thickness(0) };
paragraph.Inlines.Add(uiContainer);
MainContentTextBlock.Blocks.Add(paragraph);
}
PageWidth是DependencyProperty我在页面的SizeChanged事件处理程序中设置的。
ChildItemTemplate: _
<DataTemplate x:Name="ChildItemTemplate"
x:DataType="models:Child">
<Grid Height="18"
Margin="48 12">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="24" />
<ColumnDefinition Width="48" />
<ColumnDefinition />
<ColumnDefinition />
<ColumnDefinition Width="60" />
</Grid.ColumnDefinitions>
<FontIcon x:Name="ParentPresentIcon"
x:Load="{x:Bind ParentMustBePresent}"
FontFamily="/Assets/Fonts/Kimble.ttf#Kimble-UWP"
FontSize="16"
Foreground="{ThemeResource ApplicationSecondaryForegroundThemeBrush}"
Glyph=""
Grid.Column="0"
HorizontalAlignment="Center" />
<Border x:Name="HereCheckBox"
BorderBrush="{ThemeResource ApplicationSecondaryForegroundThemeBrush}"
BorderThickness="1"
CornerRadius="2"
Grid.Column="1"
Height="18"
HorizontalAlignment="Center"
Width="18" />
<TextBlock Grid.Column="2"
Text="{x:Bind FullName}" />
<TextBlock Grid.Column="3"
Text="{x:Bind Address}" />
<TextBlock Grid.Column="4"
HorizontalTextAlignment="Right"
Text="{x:Bind Age}" />
</Grid>
</DataTemplate>
我有两个辅助方法，PrintPage打印OverflowPage服务调用它们：
public override PrintablePage GetOverflowContent() =>
new OverflowPage(MainContentTextBlock);
和
public override bool HasOverflow() =>
MainContentTextBlock.HasOverflowContent;
然后的构造函数OverflowPage将参数的 (a RichTextBlock)OverflowContentTarget属性设置为OverflowPage's OverflowBlock。
这一切都很好。但是，我似乎遇到了一个错误。系统似乎无法正确计算HasOverflowContent属性。正如你在这张图片中看到的，有明显的溢出内容（它被剪裁了），但HasOverflowContent总是错误的。
（请注意，页面其余部分的内容正在正确呈现，但出于隐私原因，我已将其删除。）
这发生在 上OverflowPage，但我认为可以安全地假设同样的问题也会出现在 上PrintPage。
我是否遗漏了影响布局的内容，或者这是系统中的错误？
为文字墙道歉，但似乎是布局问题，我想我最好发布任何可能影响它的代码。