Defining WPF Window style in class library - wpf

Question

Currently I am developing some WPF class library, which will have several WPF Windows and trying to create my own window ControlTemplate for these Windows to make more nice design of these windows (inspired by this article: Reusing Control Templates in Resource Dictionaries).
Problem is, then it's a WPF class library not an application assembly, where i can use app.xaml and to define my resource dictionary reference & etc...
Using code below i getting an error: StaticResource reference 'MyWindowStyle' was not found
<Window x:Class="SomeERP.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300"
Style="{StaticResource MyWindowStyle}">
<Window.Resources>
<!-- My Window Style -->
<Style x:Key="MyWindowStyle" TargetType="Window">
<Setter Property="Background" Value="Transparent" />
<Setter Property="WindowStyle" Value="None" />
<Setter Property="AllowsTransparency" Value="True" />
<Setter Property="Opacity" Value="0.95" />
<Setter Property="Template" Value="{StaticResource MyWindowTemplate}" />
</Style>
<!-- Window Template -->
<ControlTemplate x:Key="MyWindowTemplate" TargetType="{x:Type Window}">
<Grid>
</Grid>
</ControlTemplate>
</Window.Resources>
</Window>
I suspect i get this error because in my case it's not predeclared before Window declaration as in application's case in app.xaml which i don't have in class libary. I am pretty new in WPF and just starting to use WPF design possibilities.

Answer 1

If you need the style only once, the solution is pretty simple: Just define the style in-place
<Window.Style>
<!-- My Window Style -->
<Style TargetType="Window">
...
</Style>
</Window.Style>
However, if you need the style in more than one window, it is reasonable to define the style in a resource dictionary. Then you can integrate the resource dictionary in the window's resources and set the style accordingly:
<Window.Resources>
<!-- My Window Style -->
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionary1.xaml"/>
<!-- path to the resource dictionary -->
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resource>
<Window.Style>
<StaticResource ResourceKey="MyWindowStyle"/>
</Window.Style>

Answer 2

Looks like i've found solution to my problem in this post: Assembly-wide / root-level styles in WPF class library and according to this post What's the difference between StaticResource and DynamicResource in WPF?
A StaticResource will be resolved and assigned to the property during the loading of the XAML which occurs before the application is actually run. It will only be assigned once and any changes to resource dictionary ignored.
A DynamicResource assigns an Expression object to the property during loading but does not actually lookup the resource until runtime when the Expression object is asked for the value. This defers looking up the resource until it is needed at runtime. A good example would be a forward reference to a resource defined later on in the XAML. Another example is a resource that will not even exist until runtime. It will update the target if the source resource dictionary is changed.
That was what i needed, as i have class library, i don't have app.xaml and can't predeclare resources for Window. I just need to use DynamicResource rather than StaticResource to get it working.
Thanks for attention :)

Answer 3

Just add the external assembly:
<Application.Resources>
<ResourceDictionary>
Source="/MyAssemblyName;component/MyResources.xaml"
</ResourceDictionary>
</Application.Resources>