Question

I have a UserControl with a Border element within it that I want to style with a particular Border style. It compiles but won’t start, giving a XamlParseException, saying, “Cannot find resource …”

Is there a way to do this?

Thanks.

App.xaml:

<cal:CaliburnApplication x:Class="WahnamProgressTracker.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.caliburnproject.org"
xmlns:Converters="clr-namespace:WahnamProgressTracker.Converters;assembly=WahnamProgressTracker"
xmlns:Model="clr-namespace:WahnamProgressTracker.Model">
<Application.Resources>
    <Style x:Key="FancyBorder"
           TargetType="{x:Type Border}">
        <Setter Property="Margin" Value="0,0,0,8"/>
        <Setter Property="Padding" Value="8"/>
        ...
    </Style>
</Application.Resources>

MainView.xaml:

<Window x:Class="WahnamProgressTracker.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.caliburnproject.org"
xmlns:uc="clr-namespace:WahnamProgressTracker.UserControls"
MinHeight="500" MinWidth="800">

<DockPanel>
    <uc:MainViewMenu x:Name="menu"
                     DockPanel.Dock="Top" />

    <StatusBar x:Name="quoteBar"                   
               DockPanel.Dock="Bottom">
        <TextBlock Text="{Binding Path=Quote.Text, Mode=OneWay}" />
    </StatusBar>

    <uc:MainViewNavigation x:Name="navigationBar"
                           DockPanel.Dock="Left" />

    <uc:ProgressGraph x:Name="graph" />
</DockPanel>

MainViewNavigation.xaml (user control):

<UserControl x:Class="WahnamProgressTracker.UserControls.MainViewNavigation"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <Border Style="{StaticResource FancyBorder}">
        ...       
    </Border>    
</UserControl>

Answer 1

Can you post a sample of what you mean? The only case in which your issue can occur is if the User Control is created and then rendered outside your application’s visual tree.

The XAML below works for me:

App.xaml:

<Application x:Class="WpfApplication1.App"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 StartupUri="Window1.xaml">
    <Application.Resources>
        <Style TargetType="{x:Type TextBlock}" x:Key="myStyle">
            <Setter Property="Foreground" Value="Green" />
            <Setter Property="FontWeight" Value="Bold" />
        </Style>
    </Application.Resources>
</Application>

Window1.xaml:

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:local="clr-namespace:WpfApplication1"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <Grid>
        <local:UserControl1 />
    </Grid>
</Window>

UserControl1.xaml:

<UserControl x:Class="WpfApplication1.UserControl1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Height="300" Width="300">
    <Grid>
        <TextBlock Style="{StaticResource myStyle}">HEY!</TextBlock>
    </Grid>
</UserControl>