I'm learning WPF. I'm trying to reference ResourceDictionary in App.xaml from AboutView.xaml to apply the materialview style.
Tried pack uri way and also "../" but VSS is still complaining "An error occurred while trying to find App.xaml".
The folder structure:
What am I doing wrong?
AboutView.xaml
App.xaml
To ASh:
So with referenced, my materialview button shows nicely.
Relying on App.xaml to apply materialview style across all Windows doesn't work if I don't reference it explicitly. The button is stripped of its style.
The app.xaml isn't a ResourceDictionary, but contains the definition for your Application (it starts with an <Application>element, not a <ResourceDictionary>). You can move your resources out of the app.xaml into their own ResourceDictionary and then reference that dictionary from your view and other elements as needed.
Related
I am using the MaterialDesign for XAML package in WPF. When I run my application, all styles and controls are rendered as expected. However in the XAML designer I have dozes of errors such as "The resource 'MaterialDesignFlatButton' could not be resolved." Example of a line that is throwing that error:
<Button Style="{StaticResource MaterialDesignFlatButton}" IsDefault="True" Margin="0 8 8 0" ...
My app.xaml contents is as follows:
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Light.xaml" />
<ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml" />
<ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Primary/MaterialDesignColor.Blue.xaml" />
<ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Accent/MaterialDesignColor.LightBlue.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
I have attempted the top solution proposed on The resource "x" could not be resolved. but that causes the project to fail to run (I believe I am not using the correct pathing when attempting to use the proposed "absolute pack URI"). So I have two questions at this point:
Is there a reason the resources would fail to resolve in the XAML designer given the way I have defined them in App.xaml (per the developer guide: https://github.com/MaterialDesignInXAML/MaterialDesignInXamlToolkit/wiki/Getting-Started)?
How can I find out the "absolute pack URI" to use for the source for my resource dictionaries?
In the past, I had problems like this.
The error causes are as follow.
1. Setup and setting config
About this, please check the github and material design homepage.
2. Build and Compiler problem
About this, users may set the "Platform Target" as "x64".
That can invoke errors because material designer tool use "x32" compiler, so please use "any cpu" or "x32".
I had this problem with the flat accent button, while every other button style worked. I added the resource for buttons, then the error was gone. Then I removed the button resource... and the error was still gone.
https://github.com/MaterialDesignInXAML/MaterialDesignInXamlToolkit/wiki/FAQ
Exception: Cannot find resource named 'MaterialDesign...'
This error typically comes when you have a static resource referencing
one of the material design styles, and have not included the
appropriate resource dictionary that contains the style. Try the
following:
Ensure that you have loaded all of the default material design styles in your App.xaml. You can find directions for this in the
Getting Started guide.
Ensure you have referenced the control specific resource dictionary that contains the style. The path for this is resource dictionary
should be .xaml" />. For example, if you were trying to reference the
MaterialDesignFloatingActionMiniButton style for a button, the
resource dictionary source would be: . Typically these inclusions are done at root of your Window, User
Control, or Template. You can find the full list of the resource
dictionaries here
Inside my WPF Application I am including a ResourceDictionary from another Project.
<Application x:Class="namespace.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<!-- This Line causes an Error -->
<ResourceDictionary Source="pack://application:,,,/Commons;Component/Generic.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
Metadata override and base metadata must be of the same type or derived type.
The solution builds successful and runs.
Restarting Visual Studio doesn't fix it.
Cut and Paste the <ResourceDictionary Source="..." /> line causes another error as explained here in the Comments:
Value Cannot be Null. Parameter Name: item. Restarting Visual Studio will then bring back the old error.
Sadly I haven't found out how to reproduce this error, I can only tell you something more about the environment im using:
Visual Studio 2015 Professional, Version 14.0.25431.01 Update 3
And allthough I doubt, those are associated with my problem, here my installed Plugins:
Resharper Ultimate 2017.1.1
GitExtensions Version 2.49.03
Sinatr's comment hinted me to read more about theming.
ThemeInfo
Inside of a Custom Control Library theres automatically created a ThemeInfoAttribute inside AssemblyInfo.cs
[assembly:ThemeInfo(
ResourceDictionaryLocation.None, //where theme specific resource dictionaries are located
//(used if a resource is not found in the page,
// or application resource dictionaries)
ResourceDictionaryLocation.SourceAssembly //where the generic resource dictionary is located
//(used if a resource is not found in the page,
// app, or any theme specific resource dictionaries)
)]
Parameters
As it states in the autogenerated comments, the first parameter is to determine wheter there exist or where to find Theme specific resource dictionaries.
The second parameter defines wheter there exist or where to find the generic ResourceDictionary (Generic.xaml).
ResourceDictionaryLocation-Enumeration
The ResourceDictionaryLocation-Enumeration itself is used to specify the location of those dictionaries.
ResourceDictionaryLocation.None
No theme dictionaries exist.
ResourceDictionaryLocation.SourceAssembly
Theme dictionaries exist in the assembly that defines the types being themed.
This expects the ResourceDictionary to be located in a /Themes-Folder. Explanation later.
ResourceDictionaryLocation.ExternalAssembly
Theme dictionaries exist in assemblies external to the one defining the types being themed.
I am not going to explain how this works.
Why /Themes-Folder
Sadly I couldn't find too much about this. If someone has some more info please share.
Have you ever wondered, how styles of a lookless control are being applied?
If one created a lookless Control, he did as follows:
public class MyControl : ControlTemplate
{
static MyControl()
{
// This tells WPF to search for a Style for this type
DefaultStyleKeyProperty.OverrideMetadata(typeof(MyControl)),
new FrameworkPropertyMetadata(typeof(MyControl)));
}
}
In short, Ressources in WPF are located, by searching up the Logical-Tree, then inside Application's Resources and finally inside sth. they call System-Area (this is my translation from German, if you know a better one pls tell).
So depending on ThemeInfo, MyControl propably had its Style inside a ResourceDictionary inside the /Themes-Folder, eg. /Themes/Generic.xaml. And that tells WPF to add the Ressources to the System-Area which finally results in automatically resolving the appropriate style.
Somewhere inside /Themes/Generic.xaml:
<Style TargetType="{x:Type MyControl}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type MyControl}">
..
</ControlTemplate/>
</Setter.Value>
</Setter>
</Style>
That's why the above ThemeInfoAttribute requires Generic.xaml to be located in a /Themes-Folder. - And somehow, even if in my case the System-Area-Functionality isn't even used for this generic file, this causes those errors. But I wasn't able to find out why.
Sources:
ThemeInfoAttribute Constructor
ResourceDictionaryLocation Enumeration
Windows Presentation Foundation - Das Umfassende Handbuch, Rheinwerk Computing Version 4
Resource dictionary merged to the Window as given in the code below.
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="DefaultTheme.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
I had created a custom control for context menu and had created the corresponding style in the DefaultTheme.xaml file. Even though at the window level it had the resource dictionary merged, the styles were not accessible for the custom controls.
Since it was custom control I had to merge the dictionary in the C# constructor like this -
const string defaultThemePath = "DefaultTheme.xaml";
var dictionary = new ResourceDictionary { Source = new Uri(defaultThemePath, UriKind.Relative) };
Resources.MergedDictionaries.Add(dictionary);
If the resource dictionary is merged, it should be available for child controls is an expectation. Is my understanding wrong about merged resource dictionary?
Edit
As #Rohit Vats has rightly pointed, my custom control is context menu and it is not part of the visual child of the window. Hence it does not have the resource dictionary inherited.
I just quickly check by putting one SolidColorBrush in random ResourceDictionary and merge it under App resources and use that resource from ContextMenu and ContextMenu was able to access the resource.
From MSDN, StaticResource lookup behaviour works like this:
The lookup process checks for the requested key within the resource
dictionary defined by the element that sets the property.
The lookup process then traverses the logical tree upward, to the
parent element and its resource dictionary. This continues until the
root element is reached.
Next, application resources are checked. Application resources are
those resources within the resource dictionary that is defined by the
Application object for your WPF application.
As evident from the above assertion, it looks for logical parent and not Visual parent and in case resource is not found anywhere, it looks for resource under App resources.
So, your case for ContextMenu will work if you merge resources under App resources.
I'm trying to use resource files (.resx) in a class library. I'm having trouble using these resources in my library's XAML files because libraries do not come with an App.xaml file. So I can not do:
<Application.Resources>
<local:LocalizedStrings xmlns:local="clr-namespace:WPLocalization" x:Key="LocalizedStrings" />
</Application.Resources>
How do I go about localizing a self-contained WP8 library/assembly?
I found a way but it's rather a work around.
The solution is not to try to localize your controls from XAML, but instead from your behind code.
For example, you define a Button in XAML as follows:
<Button Name="MyButton" />
And then in your partial class behind you set the content of the button programatically as follows:
MyButton.Content = MyLocalizedStrings.Hello;
Of course, in this example you would have a resource file called "MyLocalizedStrings.resx" in your project with a string named "Hello" in it.
This approach solves the problem. The only down side is that you won't be able to see a preview of the localized XAML in the Visual Studio XAML window.
I have set up a Prism project with one module. In the module I have defined some views. I want to use a ResourceDictionary to style UI elements.
However...if I include the following code in the View1.xaml
i get the following error
Warning 1 The designer does not support loading dictionaries that mix 'ResourceDictionary' items without a key and other items in the same collection. Please ensure that the 'Resources' property does not contain 'ResourceDictionary' items without a key, or that the 'ResourceDictionary' item is the only element in the collection.
Here is the code:
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../Resources/ResourceDictionary.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</UserControl.Resources>
If I include the code in the App.xaml file the style looks applied in the designer, but when I run the project i get the following error:
Cannot find a Resource with the Name/Key
Do you have any useful advices how to use ResourceDictionary styles with Prism and MVVM?
Thanks
Maybe this guy here had a similar problem:
http://blog.caraulean.com/2011/09/13/how-to-make-caliburn-micro-and-silverlight-resources-in-mergeddictionaries-play-nicely-together/
Have a check