LayoutRounding property is not defined - wpf

I have taken a copy of the XamlVirtualJoystick project located here
https://github.com/shakram02/XamlVirtualJoystick
I wanted to convert it from a UserControl to a custom control, with the XAML code in a resource dictionary. (I don't know if that is relevant to the my error.)
In my project, the identical XAML generates the error message:
The property 'LayoutRounding' does not exist in XML namespace 'http://schemas.microsoft.com/expression/blend/2008'.
This refers to the property d:LayoutRounding="Auto", where the prefix d is defined as
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
I can compile the original project, so the property must be defined somewhere, but I cannot figure out where.
Where is the property LayoutRounding defined?

do you have mc:Ignorable="d" in your xaml defined? d is usually the designer name space and mc:Ignorable="d" says that all properties with prefix d: are to be ignored by the compliler and are only used in blend designer view.

Related

IOException when referencing App.xaml's ResourceDictionary

I'm trying to reference App.xaml's ResourceDictionary from a separate WPF window. I want to use resources from there in different windows, and this seems like the recommended way to do it. Unfortunately, I don't seem to be able to effectively reference App.xaml from the other window. Here is my App.xaml:
<Application x:Class="View.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:ViewModel="clr-namespace:ViewModel;assembly=ViewModel"
xmlns:local="clr-namespace:View"
StartupUri="ClockView.xaml">
<Application.Resources>
<ResourceDictionary>
<local:PriorityToIconConverter x:Key="PriorityToIconConverter" />
</ResourceDictionary>
</Application.Resources>
Notes: I'm not using MainWindow, so I've replaced the startup URI with a form that always comes up. I noted that in some other answers, the location of MainWindow is sometimes the issue. In my case, I haven't seen any difference between using ClockView or MainWindow. Both ClockView and MainWindow exist in the root namespace, MainWindow is just never loaded. I also have more resources, but I've removed them for the sake of conciseness.
Here's a simplified example of the code where I'm trying to reference the ResrouceDictionary from App.xaml:
<local:AssistantWindow
x:Class="View.AutomatorView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
xmlns:properties="clr-namespace:View.Properties"
xmlns:local="clr-namespace:View"
mc:Ignorable="d"
Title="Tool"
x:Name="Tool"
Background="Transparent"
Height="600"
Width="450"
Topmost="{Binding Source={x:Static properties:Settings.Default}, Path=ToolAlwaysOnTop}"
MinHeight="515"
MinWidth="150">
<Window.Resources>
<ResourceDictionary Source="App.xaml" />
</Window.Resources>
Again, this is simplified to be concise. When I try to load this form, I get the exception:
System.Windows.Markup.XamlParseException: ''Set property 'System.Windows.ResourceDictionary.Source' threw an exception.' Line number '21' and line position '10'.'
Inner Exception
IOException: Cannot locate resource 'tool/app.xaml'.
The view for "Tool" is located in a folder that is also named "Tool." However, the xaml and code behind don't reference this namespace, I'm just using the folder to organize my classes. It looks like it's looking for App.xaml in the folder the view resides in. App.xaml resides in the root namespace (View). I've tried modifying the source in the xaml for Tool to:
- View.App.xaml
- View:App.xaml
- View/App.xaml
How can I get this reference to work, so I can share resources throughout my application? Thank you.
You can't load App.xaml like you're trying to do because it's not actually a ResourceDictionary. You can only specify ResourceDictionary files as the target of Source.
However, if you declare a resource in App.xaml, you can reference it anywhere without needing to load the file it's in. That's done for you automatically. Therefore, you can reference your converter at any time with {StaticResource PriorityToIconConverter}.
Note that if you moved it from the default starting location (the base project folder) you may have to update its location. Right click your project, then Properties. Navigate to the "Application" tab (should be the uppermost element on the left-hand sidebar) and look for the "Startup object" field. Set that to [ProjectName].[Namespace?].[Namespace?].App. When I tested it, mine worked without needing to manually change the location, but your setup may be different.

WPF ResourceDictionary Key Property "Key" was not found

I created a DateTimeConverter to convert my datetimes to MM/dd/yyyy format. I tried using it in my xaml file as:
<Window.Resources>
<converters:DateTimeConverter Key="DateTimeConverter"/>
</Window.Resources>
and it caused an error saying: Property Key was not found in type DateTimeConverter.
Then after a bit of googling, I changed it to:
<Window.Resources>
<converters:DateTimeConverter x:Key="DateTimeConverter"/>
</Window.Resources>
and it worked (note the "x:" before Key).
My "x" is defined by default as: xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
It is working now, but I don't know why. Can someone please throw some light?
Adding an x:Key value to a XAML object element is the most common way to identify a resource in a resource dictionary.
It's the syntax chosen for WPF xaml. Key property or attribute doesn't exist.
Refer to MSDN specs for more clarification.

Setting design time DataContext on a Window is giving a compiler error?

I have the following XAML below for the main window in my WPF application, I am trying to set the design time d:DataContext below, which I can successfully do for all my various UserControls, but it gives me this error when I try to do it on the window...
Error 1 The property 'DataContext' must be in the default namespace or in the element namespace 'http://schemas.microsoft.com/winfx/2006/xaml/presentation'. Line 8 Position 9. C:\dev\bplus\PMT\src\UI\MainWindow.xaml 8 9 UI
<Window x:Class="BenchmarkPlus.PMT.UI.MainWindow"
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:UI="clr-namespace:BenchmarkPlus.PMT.UI"
xmlns:Controls="clr-namespace:BenchmarkPlus.PMT.UI.Controls"
d:DataContext="{d:DesignInstance Type=UI:MainViewModel, IsDesignTimeCreatable=True}"
Title="MainWindow" Height="1000" Width="1600" Background="#FF7A7C82">
<Grid>
<!-- Content Here -->
</grid>
</Window>
I needed to add the mc:Ignorable="d" attribute to the Window tag. Essentially I learned something new. The d: namespace prefix that Expression Blend/Visual Studio designer acknowledges is actually ignored/"commented out" by the real compiler/xaml parser!
<Window
...
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
...
/>
The following was taken from
Nathan, Adam (2010-06-04). WPF 4 Unleashed (Kindle Locations 1799-1811). Sams. Kindle Edition.
Markup Compatibility
The markup compatibility XML namespace (http://schemas.openxmlformats.org/markup-compatibility/2006, typically used with an mc prefix) contains an Ignorable attribute that instructs XAML processors to ignore all elements/attributes in specified namespaces if they can’t be resolved to their .NET types/members. (The namespace also has a ProcessContent attribute that overrides Ignorable for specific types inside the ignored namespaces.)
Expression Blend takes advantage of this feature to do things like add design-time properties to XAML content that can be ignored at runtime.
mc:Ignorable can be given a space-delimited list of namespaces, and mc:ProcessContent can be given a space-delimited list of elements. When XamlXmlReader encounters ignorable content that can’t be resolved, it doesn’t report any nodes for it. If the ignorable content can be resolved, it will be reported normally. So consumers don’t need to do anything special to handle markup compatibility correctly.
Wow, what a pain! Let's hope MS puts in some VS design-time support for x:Bind.
We to be able to use the VS designer but also be able to switch easily to x:Bind instead of Binding. Here's what I did:
In my View, I added a property to get my ViewModel. This makes sense because x:Bind paths are relative to the Page (i.e. the View object).
In my Page XAML, I added the following to the <Page ... > at the top of the XAML:
mc:Ignorable="d"
d:DataContext="{d:DesignInstance Type=local:MyView, IsDesignTimeCreatable=False}"
DataContext="{x:Bind}"
This way, the Page's actual data context is set to the Page itself due to the {x:Bind}. That's because x:Bind is relative to the Page and there is no path given.
At the same time, due to the d:DataContext line, the VS designer reflects on the MyView class (without creating an instance) for the purpose of the VS designer interaction. This lets VS design from MyView, where you can then scroll down to the ViewModel property, expand it and select the item that you want to bind to.
When you do all that, the VS designer will create a Binding statement whose path is relative to the View, i.e. it happens to be exactly the same as the path that x:Bind expects. So, if you want to switch to x:Bind later on, you can just search and replace all "{Binding" with "{x:Bind".
Why do we even need the d:DataContext line to tell VS what class to look at? Good question, since you would think that VS could figure out the very next line sets the DataContext to the Page, using DataContext={x:Bind}. Go ahead and try it, it does not work and neither does it work if you change x:Bind to Binding relative to self.
Hopefully this situation will get cleaned up by MS !!
If you are not tooo fussy on the data have a look at the sample data found in xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
You use it like this...
<ItemsControl ItemsSource="{Binding Path=Report.Audit.Data}" d:ItemsSource="{d:SampleData}" Grid.Row="1">
<ItemsControl.ItemTemplate>
<DataTemplate>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
it then renders the items control with a few rows of data
I've solved the problem adding d:DataContext="{d:SampleData}" in the component definition (UserControl or Window).
<UserControl x:Class="TestControl"
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:local="clr-namespace:TestApp.Views"
DataContext="{Binding TestViewModel}"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800"
d:DataContext="{d:SampleData}"
>

xamlparseexception was unhandled

Cannot create instance of 'Window1' defined in assembly 'WpfApplication1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. Exception has been thrown by the target of an invocation. Error in markup file 'Window1.xaml' Line 1 Position 9.
how do i solve this issue?
line 1 of my window1.xaml file:
<Window x:Class="WpfApplication1.Window1"
As pointed out by #Jeff, the first line (root) of the xaml file should be something like this,
<Window x:Class="WpfApplication1.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">
From XAML Overview
The root element also contains the attributes xmlns and xmlns:x. These attributes indicate to a XAML processor which XAML namespaces contain the type definitions for backing types that the markup will reference as elements. The xmlns attribute specifically indicates the default XAML namespace.
Within the default XAML namespace, object elements in the markup can be specified without a prefix. For most WPF application scenarios, and for almost all of the examples given in the WPF sections of the SDK, the default XAML namespace is mapped to the WPF namespace http://schemas.microsoft.com/winfx/2006/xaml/presentation. The xmlns:x attribute indicates an additional XAML namespace, which maps the XAML language namespace http://schemas.microsoft.com/winfx/2006/xaml.
Don't remove the x namespace that comes included in XAML files by default. Otherwise it would be invalid. It seems you did so the parser has no idea what the x namespace is referring to. You should have these lines somewhere within the root:
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

ContextMenu static resource compile error

I've created a Silverlight control with a ContextMenu property. I've also created a ContextMenu static resource, which one I want to add to the control, but I get a compile error.
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:controlsInputToolkit="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Input.Toolkit" >
<controlsInputToolkit:ContextMenuService.ContextMenu x:Key="FilterableTreeViewContextMenu">
<controlsInputToolkit:ContextMenu>
<controlsInputToolkit:MenuItem Header="New" />
</controlsInputToolkit:ContextMenu>
</controlsInputToolkit:ContextMenuService.ContextMenu>
</ResourceDictionary>
The error:
Unexpected ATTRIBUTE in parse rule PropertyElement ::= . PROPERTYELEMENT Content? ENDTAG..
Any idea?
This error indicates that an attribute has been applied to a property element which is not valid. In your case, this is the x:Key attribute on the controlsInputToolkit:ContextMenuService.ContextMenu element. You will need to remove it.
You can identify property elements in XAML by the period that is included within the name of the element. The part of the name prior to the period is the name of a class and the part that follows is a property on that class. Attributes are not allowed within such elements.
Your XAML was compact enough for me to easily find the problem. If this error occurs within a much larger XAML file, then the following regular expression can be used within Visual Studio to locate the problem. Just make sure to check the 'Use' checkbox in the 'Find and Replace' dialog and select 'Regular Expressions' in the combo box.
\<:Al#.:Al# :Al#=\".#\":b#>
If you need to adjust the expression then the MSDN documentation on regular expression syntax will be useful.

Resources