As I have multiple Windows in my application, I am looking for a solution that does not require me to set a binding on each Window.
I created a ResourceDictionary which has a style for the Window Background:
<Style TargetType="{x:Type Window}">
<Setter Property="Background" Value="AliceBlue"/>
</Style>
In my XAML, I set the ResourceDictionary:
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Templates.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
There is no error, but my Window color stays white.
This appears to be caused by a combination of the order in which WPF loads/processes styles from nested ResourceDictionary, and the specifics of the Window class.
Assume MainWindow is defined as per your post. Now put the following in Templates.xaml:
<Style TargetType="{x:Type Window}">
<Setter Property="Background" Value="Red"/>
</Style>
<Style TargetType="{x:Type Window}" x:Key="myStyle">
<Setter Property="Background" Value="Green"/>
</Style>
If MainWindow has no style defined, then you will see that in the designer it appears with a red background. The designer is parsing the whole Xaml and loading the resource dictionary, and then drawing the results. The style is read before the window is drawn, and so the red background is applied.
When you run the application, the window is created before the ResourceDictionary is applied. It looks for a default style (a style with x:Key="{x:Type Window}") before the nested ResourceDictionary is processed, and finds nothing. Therefore at runtime, the window appears with default colour. (This is the behaviour described in the comments above.) Remember that the style with x:Key="{x:Type Window}" has a default value that matches the Windows style.
This is borne out if you use myStyle explicitly. If you add to your Window definition the attribute Style="{StaticResource myStyle}" you'll find that the designer fails, but you also get a run-time error, because myStyle hasn't been created at the time that the Window needs it. If you switch to Style="{DynamicResource myStyle}" then you'll see that it works as you hope, because DynamicResource will update once the ResourceDictionary has been parsed and the style included.
So, applying this, you can fix the problem in one way by adding this to your Window element: Style="{DynamicResource {x:Type Window}}" - but this is cludgy. The better solution is to include your resource dictionary in the app.xaml file, where it will be parsed before any window is opened and thus available to all:
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Templates.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
The real issue here is that your Window is not really a Window: it is a class that derives from Window and will in fact be MainWindow, Window2, etc... This means that the automatic style wireup for a Window will never work in this way, and some level of manual binding will unfortunately always be required.
This is the solution I used in my application. It lets me keep all my window styles together, and requires just a couple lines after the <Window.Resources> section.
Do your Style like so:
<Style x:Key="MyWindowStyle">
<Setter Property="Window.Background" Value="AliceBlue"/>
</Style>
Then, in your Window, after </Window.Resources> include the following:
<Window.Style>
<Style BasedOn="{StaticResource MyWindowStyle}"/>
</Window.Style>
Add a new brush in your resource dictionary
<SolidColorBrush x:Key="WindowBackground" Color="AliceBlue" />
and in your WPF window simply set the required resource to the window background property
<Window x:Class="GDD.Presentation.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="300" Width="300"
Background="{StaticResource WindowBackground}">
Related
If I have a simple childcontrol that already have a style defined for a element in the childcontrol.
Can I change that style of that element from the parent control?
If I dont set the style in the childcontrol I can override it from the parent control, but I cant seem to get it to work when the style is set.
I can't change the code in the childcontrol.
The example childcontrol:
<UserControl
x:Class="TestingThemes.ChildControl"
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:local="clr-namespace:TestingThemes"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
d:DesignHeight="450"
d:DesignWidth="800"
mc:Ignorable="d">
<UserControl.Resources>
<Style x:Key="aw" TargetType="Button">
<Setter Property="Foreground" Value="Blue" />
</Style>
</UserControl.Resources>
<Grid>
<Button
Width="100"
Height="50"
Content="Kalle Anka"
<!-- If I remove the style I can override it from parent control -->
Style="{DynamicResource aw}" />
</Grid>
</UserControl>
The parentcontrol:
<Grid>
...
<local:ChildControl>
<local:ChildControl.Resources>
<!--<Style BasedOn="{StaticResource local:ResourceKey=aw}" TargetType="Button">-->
<Style TargetType="Button">
<Setter Property="Foreground" Value="Red" />
</Style>
</local:ChildControl.Resources>
</local:ChildControl>
</Grid>
This is possible, but you must change the location of the initial Style.
The XAML engine will traverse the logical tree to lookup StaticResource/DynamicResource resources for an element (e.g., Button) starting locally, with the local ResourceDictionary.
This means, you want the default Style that is defined inside the UserControl to be found at the very end of the lookup route - after any potential custom styles that are intended to override the default Style. To accomplish this, you must move the Style either to App.xaml or Generic.xaml.
Additionally, the reference must be DynamicResource in order to defer the lookup to the moment the logical tree is composed. The overriding Style can be defined anywhere up the route towards the tree root.
Since Generic.xaml provides a different name scope, you would have to define a unique static (global in terms of the XAML name scopes) ComponentResourceKey which you would have to use as the style's x:Key value (in case you plan to move the default Style to the Generic.xaml file).
Because of the aforementioned XAML resource lookup behavior, creating a custom Control is always prefereable over a UserControl when you plan to make the control customizable (like in your case). The default Style of a custom Control is located in the Generic.xaml by default, thus you would have never ran into your current issue.
ChildControl.xaml
<UserControl>
<Grid>
<Button Style="{DynamicResource aw}" />
</Grid>
</UserControl>
App.xaml
The last lookup location before the Generic.xaml. If a Style with the same key was not found yet, the Style found in App.xaml will be applied.
<Style x:Key="aw" TargetType="Button">
<Setter Property="Foreground" Value="Blue" />
</Style>
ParentControl.xaml
<ChildControl>
<ChildControl.Resources>
<Style x:Key="aw" TargetType="Button">
<Setter Property="Foreground" Value="Red" />
</Style>
</ChildControl.Resources>
</ChildControl>
I know I can set the style of a UserControl like so in the control by adding an attribute:
Style="{StaticResource MyStyle}"
And having a style in my ResourceDictionary that looks something like the following:
<Style x:Key="MyStyle" TargetType="{x:Type UserControl}">
<Style.Resources>
<Style TargetType="Label">
<!-- Label Setters -->
</Style>
<Style TargetType="TextBox">
<!-- TextBox Setters -->
</Style>
</Style.Resources>
</Style>
But is there a way I can set the style of the UserControl in the ResourceDictionary directly like:
<Style x:Key="MyStyle" TargetType="{x:Type MyControl}">
Essentially my question is, can I apply the style directly to the control instead of to the controls components?
EDIT:
What I am trying to accomplish is something like the following:
<Style x:Key="MyStyle" TargetType="{x:Type MyControl}">
<Setter Property="Background" Value="Black"/>
</Style>
<Style x:Key="{x:Type MyControl}" TargetType="{x:Type MyControl}" BasedOn="{StaticResource MyStyle}"/>
Where the second line applies the style to all controls in the application, if you do something similar with a normal control this approach works.
However this only sets the Background of the UserControl, so how can I apply that same background to its components.
How can I do it with the UserControl?
You can directly set the UserControl's Style like this:
<UserControl x:Class="MyNamespace.MyControl" xmlns:local="MyNamespace" ...>
<UserControl.Style>
<Style>
<Setter Property="local:MyControl.MyProperty" Value="..."/>
...
</Style>
</UserControl.Style>
</UserControl>
or like this:
<UserControl x:Class="MyNamespace.MyControl" xmlns:local="MyNamespace" ...>
<UserControl.Style>
<Style TargetType="local:MyControl">
<Setter Property="MyProperty" Value="..."/>
...
</Style>
</UserControl.Style>
</UserControl>
A default Style in the UserControl's Resources should also work:
<UserControl x:Class="MyNamespace.MyControl" xmlns:local="MyNamespace" ...>
<UserControl.Resources>
<Style TargetType="local:MyControl">
<Setter Property="MyProperty" Value="..."/>
...
</Style>
</UserControl.Resources>
</UserControl>
You need to remove the x:Key from your defined style so that it can be applied universally to all controls of the same type as what is defined in the TargetType.
To quote from MSDN for Style.TargetType Property:
Setting the TargetType property to the TextBlock type without setting an x:Key implicitly sets the x:Key to {x:Type TextBlock}. This also means that if you give the [...] Style an x:Key value of anything other than {x:Type TextBlock}, the Style would not be applied to all TextBlock elements automatically. Instead, you need to apply the style to the TextBlock elements explicitly.
Necro answer for a special case. If the user control is selected via a DataTemplate resource in another WPF control or window, WPF may not automagically apply a default style from an imported resource dictionary. However, you can apply named style resource after importing a resource dictionary.
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../../Resources/ResourceDictionary.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</UserControl.Resources>
<UserControl.Style>
<Binding Source="{StaticResource MyUserControlStyle}"></Binding>
</UserControl.Style>
To style all controls, add your ResourceDictionary to the resources of your App.xaml.
<Application.Resources>
<!-- Your Resources for the whole application here -->
</Application.Resources>
If your open your Mainwindow with the App...
<Application ...
MainWindow="MainWindow">
or during the startup event...
<Application ...
MainWindow="MainWindow">
Startup="Application_Startup">
the resources are available in every control of your MainWindow.
To set the style for a specific usercontrol look here:
Set Style for user control
in your user control xaml place the style inside the resources tag:
<UserControl>
<UserControl.Resources>
<Style ...</Style>
</UserControl.Resources>
//.. my other components
</UserControl>
I've creat a ResourceDictionary named Dictionary1.xaml, here is code:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Style TargetType="{x:Type Window}">
<Setter Property="Background" Value="Red">
</Setter>
</Style>
I ref it in App.xaml or MainWindow.xaml like this:
<Application.Resources>
<ResourceDictionary Source="Dictionary1.xaml" />
</Application.Resources>
<Window.Resources>
<ResourceDictionary Source="Dictionary1.xaml" />
</Window.Resources>
And in View Designer, window's background changes to red, but when the application is running, it's background is default(white), why? How to do it ?
you can set other controls' style in this way,except Window! try to set sytle for Button,Lable and so on, you will get a correct result. But for a Window, you will not.
see my another answer ,it may help you: How to add a common control on all my Windows?
you must set the Style's x:Key and set the Window's style explicitly:
Style="{DynamicResource key_name}"
why the View Designer shows a correct result? it may be a bug. vs2012/13's xaml Designer has many bugs, you can search or commit in msdn.I've commit one in it :
https://connect.microsoft.com/VisualStudio/feedbackdetail/view/925324/multibinding-report-an-issue-on-latest-vs-xaml-editor
but ms closes it and they will not repaire it recently.
Some information related to problem: http://www.11011.net/archives/000692.html
Specific situation is : there is some generic textblock (key equals to type) styles declared in app.xaml which is in third party app, they used by all contentpresenters in my views ignoring my own styles.
I've found few possible solutions:
Explicitly assign all elements a style with overriden template & add resource dictionary with my styles to contentpresenter resources.
Add datatemplate for string, but there is a problem with access text detection ( may be solved by placing contentpresenter with ref to my own resources, isn't good solution because we increasing visual tree just to fix this problem)
Probably any other solutions?
P.S.: There is alot of views already exist, so first option is alot of work!
To reproduce create new wpf project and modify next files:
App.xaml add generic style:
<Application.Resources>
<Style TargetType="TextBlock">
<Setter Property="FontSize" Value="20"/>
</Style>
</Application.Resources>
MainWindow.xaml content is:
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionary.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
<StackPanel>
<Button Content="Hello world">
<Button.ContextMenu>
<ContextMenu>
<MenuItem Header="Access_Text"/>
<MenuItem Header="NormalText"/>
</ContextMenu>
</Button.ContextMenu>
</Button>
<TextBlock Text="WELCOME TO BLACK MESA"/>
</StackPanel>
Add Dictionary.xaml resource dictionary and add next style inside:
<Style TargetType="TextBlock">
<Setter Property="FontSize" Value="8"/>
</Style>
Not sure where you might do it as I don't understand the structure of your App, but if you want to remove the style from the Application Resources you could do it programatically like this
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
ResourceDictionary dic = App.Current.Resources;
dic[typeof (TextBlock)] = null;
}
}
Using the XAML you provided in a test WPF project this leaves me with the default font size of 12 rather than 20.
I define a custom look for Button control in a resource dictionary:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Style TargetType="Button" x:Key="BaseButtonStyle">
<Setter Property="Background" Value="Blue"/>
</Style>
</ResourceDictionary>
Then I try to change the style of the window where the buttons are located.
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionary.xaml"/>
<ResourceDictionary>
<Style TargetType="Button" BasedOn="{StaticResource BaseButtonStyle}">
<Setter Property="Foreground" Value="Red"/>
</Style>
</ResourceDictionary>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
I have what I expected in WPF designer: a blue button with red text.
But in run-time, both styles are not applied and the button has default colors.
How can I fix this?
The one below works. I just moved the Style out of the MergedDictionaries and placed it on the outer ResourceDictionary.
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Dictionary.xaml"/>
</ResourceDictionary.MergedDictionaries>
<Style TargetType="Button" BasedOn="{StaticResource BaseButtonStyle}">
<Setter Property="Foreground" Value="Red"/>
</Style>
</ResourceDictionary>
</Window.Resources>
In your original XAML, I'm not sure why the designer was able to render it correctly while the WPF runtime didn't. The MSDN documentation says though that:
A merged ResourceDictionary does not have resource elements defined within it in markup. Instead, the merged dictionary is a ResourceDictionary with no markup child elements defined (or with no elements added through code), but with a URI specified for Source.
It might have something to do with it.