I have a Styles.xaml that groups many ResourceDictionary
s inside a MergedDictionary
.
I imported Styles.xaml in my UserControl.Resources
<UserControl.Resources>
<ResourceDictionary Source="Dictionaries\Styles.xaml" />
</UserControl.Resources>
but when I try to add a converter
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionaries\Styles.xaml" /> <--! Exception -->
</ResourceDictionary.MergedDictionaries>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
</ResourceDictionary>
</UserControl.Resources>
it raises
ArgumentNullException: Value cannot be null.
Parameter name: item
Wrapping the converter inside another MergedDictionary
has no effect.
How can I solve this?
Thank you all!
I eventually figured it out: the Exception
was raised inside one the .xaml files, but Visual Studio does not provide enough info to locate the faulty line.
Following code does work.
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionaries\Styles.xaml" />
</ResourceDictionary.MergedDictionaries>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
</ResourceDictionary>
</UserControl.Resources>
Try this
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="pack://application:,,,/PROJECTNAMESPACE (TestProject.Something);component/Dictionaries/Styles.xaml" />
</ResourceDictionary.MergedDictionaries>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
</ResourceDictionary>
</UserControl.Resources>