WPF窗口在调整大小之前不会呈现内容？

Question

我有一个简单的WPF对话框，显示程序中发生的任何错误。它绑定的视图模型非常简单，只是一个文本属性和一个显示错误列表的列表属性。但是，当我在我的应用程序中显示此对话框时，它显示为空，它只是标题栏和一个完全白色的窗口。只要我调整窗口大小，所有内容就会正确填充。为什么会这样？这是窗口的构造函数：

    public Wnd_Errors(string description, List<GamutError> ers)
    {
        InitializeComponent();
        _myVM = new ErrorWindowVM()
        {
            DescriptionText = description,
            Errors = ers,
        };
        DataContext = _myVM;
    }

以下是窗口的整个XAML：

<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation" x:Class="SPTR.Gamut.Wnd_Errors" 
             mc:Ignorable="d" 
        Title="Gamut | Errors"
        WindowStartupLocation="CenterScreen"
        Icon="Images/Icon_Gamut.ico"
        Height="442" Width="846">
    <Window.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="SPECtrumStyles.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Window.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="*" />
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <Grid Background="{StaticResource br_RibbonBackdrop}">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto" />
                <ColumnDefinition Width="*" />
            </Grid.ColumnDefinitions>
            <Image Source="Images/Icon_Error.png" Margin="10" />
            <TextBlock x:Name="tb_Desc" Grid.Column="1" FontWeight="Bold" Margin="5" Text="{Binding DescriptionText}"
                       TextWrapping="Wrap" />
        </Grid>
        <telerik:RadGridView Grid.Row="1" AutoGenerateColumns="False" RowIndicatorVisibility="Collapsed" GridLinesVisibility="Horizontal"
                             CanUserFreezeColumns="False" EditTriggers="None" CanUserDeleteRows="False" CanUserInsertRows="False" 
                             ItemsSource="{Binding Errors}" CanUserSelect="False">
            <telerik:RadGridView.Columns>
                <telerik:GridViewDataColumn Header="Error Type" DataMemberBinding="{Binding ErrorTypeText}" />
                <telerik:GridViewDataColumn Header="Message" DataMemberBinding="{Binding UIText}"
                                            TextWrapping="Wrap" Width="*" />
                <telerik:GridViewDataColumn Header="Internal Error" DataMemberBinding="{Binding ErrorTypeText}">
                    <telerik:GridViewDataColumn.CellTemplate>
                        <DataTemplate>
                            <ScrollViewer MaxWidth="800" VerticalScrollBarVisibility="Auto"
                                          HorizontalScrollBarVisibility="Auto">
                                <TextBlock Text="{Binding InternalMessage, Mode=OneWay}" />
                            </ScrollViewer>
                        </DataTemplate>
                    </telerik:GridViewDataColumn.CellTemplate>
                </telerik:GridViewDataColumn>
                <telerik:GridViewDataColumn Header="Stack Trace" DataMemberBinding="{Binding ErrorTypeText}"
                                            IsVisible="{Binding ShowStackTrace}">
                    <telerik:GridViewDataColumn.CellTemplate>
                        <DataTemplate>
                            <ScrollViewer MaxHeight="250" VerticalScrollBarVisibility="Auto" 
                                          HorizontalScrollBarVisibility="Auto">
                                <TextBox Text="{Binding Stack, Mode=OneWay}" />
                            </ScrollViewer>
                        </DataTemplate>
                    </telerik:GridViewDataColumn.CellTemplate>
                </telerik:GridViewDataColumn>
            </telerik:RadGridView.Columns>
        </telerik:RadGridView>
        <CheckBox Grid.Row="2" Content="Show Stack Trace (for error reporting)" 
                  IsChecked="{Binding ShowStackTrace, Mode=TwoWay}" Margin="5,3" />
        <Grid Grid.Row="3" Background="{StaticResource br_BaseBar}">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="48*"/>
                <ColumnDefinition Width="371*"/>
            </Grid.ColumnDefinitions>
            <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Margin="0,0,10,0" Grid.Column="1">
                <Button Margin="5" Content="OK" HorizontalAlignment="Right" Width="75" IsDefault="True" 
                        x:Name="btn_OK" Click="btn_OK_Click" />
                <Button Margin="5" Content="Cancel" HorizontalAlignment="Right" Width="75" IsCancel="True" 
                        x:Name="btn_Cancel" Click="btn_Cancel_Click" />
            </StackPanel>
            <Button Content="Export to .xlsx" Width="100" Margin="5" HorizontalAlignment="Left" 
                    x:Name="Button2" Click="Button2_Click" Grid.ColumnSpan="2" />
        </Grid>
        <Separator Grid.Row="2" VerticalAlignment="Bottom" Margin="-1" Background="{StaticResource Br_Orange}" />
    </Grid>
</Window>

正如你所看到的，我甚至没有订阅任何窗口事件来拥有任何类型的自定义处理程序，可以抑制任何事情......

我甚至在哪里开始尝试调试它？这是应用程序中唯一执行此操作的窗口（至少是我遇到的唯一一个窗口）。