I have a very simple UserControl with some borders and some decorations that react to mouseOver, pressed and some nice things.
I want to allow people to set the content of the text from outside, but when I set the content, the generated content presenter overwrites my whole WPF structure.
This is what I tried so far:
<UserControl tags tags tags>
<!-- This is the only way I found to style the textblock that WPF -->
<!-- generates to encapsulate the content string -->
<UserControl.Template>
<ControlTemplate TargetType="UserControl">
<TextBlock Background="Green"
HorizontalAligment="Center"
VerticalAlignment="Center"
Text = "{TemplateBinding Content}"/>
</ControlTemplate>
</UserControl.Template>
<!-- Here my borders and fancy things. I want to add animations -->
<!-- and react to mouseOver and Pressed like a button -->
<Border x:Name="SuperNiceBorder" tag tag tag>
<HERE I WANT THE CONTENTPRESENTER>
</Border>
</UserControl>
Is there a way to tell WPF I want the text set by the user in the Content just there ???
Move all your animations and triggers inside the ControlTemplate.
Replace your TextBlock with a ContentPresenter:
<UserControl x:Class="MySolution.MyControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<UserControl.Template>
<ControlTemplate TargetType="UserControl">
<Border x:Name="MyBorder" Background="Green">
<ContentPresenter
HorizontalAlignment="Center"
VerticalAlignment="Center"
Content = "{TemplateBinding Content}"/></Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="MyBorder" Property="Background" Value="Red"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</UserControl.Template>
</UserControl>
And you can use the UserControl like these examples:
1:
<local:MyControl Content="Test Testing tester"/>
2:
<local:MyControl>
<TextBlock Text="Another test from a TextBlock"/>
</wpfAllPurposesTest:MyControl>
I have Style that applies to all of the buttons of my application:
<Style TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
<Setter Property="Background" Value="Red" />
<Setter Property="Foreground" Value="Black" />
<Setter Property="FontSize" Value="16" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse x:Name="StatusButtonCircle" Stroke="Black" StrokeThickness="0" Fill="AliceBlue" Stretch="Uniform">
<Ellipse.Width>
<Binding ElementName="StatusButtonCircle" Path="ActualHeight"/>
</Ellipse.Width>
</Ellipse>
<Ellipse x:Name="StatusButtonCircleHighlight" Margin="4" Stroke="Black" StrokeThickness="2" Stretch="Uniform">
<Ellipse.Width>
<Binding ElementName="StatusButtonCircleHighlight" Path="ActualHeight"/>
</Ellipse.Width>
</Ellipse>
<ContentPresenter HorizontalAlignment="Center"
VerticalAlignment="Center"/>
</Grid>
<ControlTemplate.Triggers>
... some Triggers here
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
How can I change properties (e.g. FontWeight, FontSize etc.) in XAML? I tried this:
<Button FontWeight="Bold" FontSize="30" Foreground="Red">
</Button>
In the designer-view, I see the changes. But during runtime those changes are not applied.
After some investigation, I also have a Style for all TextBlock like this:
<Style TargetType="{x:Type TextBlock}">
<Setter Property="FontSize" Value="16" />
<Setter Property="FontFamily" Value="Segoe UI Semibold" />
<Setter Property="Foreground" Value="White" />
</Style>
This Style seems to override the TextBlock that is used on the Button. I still can't change the Text Properties in XAML.
Here's what it looks like if I use the Styles above in an empty project:
In the designer, the changes are applied, during runtime the one from the TextBlock are applied. If I assign a x:Key to the TextBlock, it works fine. But then I have to assign this Style to every TextBlock used in the app manually.
You are facing typical style inheritance issue in wpf.
A control looks for its style at the point when it is being initalized. The way the controls look for their style is by moving upwards in logical tree and asking the logical parent if there is appropriate style for them stored in parent's resources dictionary.
In your case, you are using ContentPresenter in button as a default behaviour. and it is using TextBlock to represent text in button by default.
Therefore at the time of initialization, ContentPresenter finding TextBlock style and applying to represent content in button.
If you want to restrict ContentPresenter to look for the style then you have to bind a blank style to content presenter so that it will not look for any further style.
<Style TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
<Setter Property="Background" Value="Red" />
<Setter Property="Foreground" Value="Black" />
<Setter Property="FontSize" Value="16" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse x:Name="StatusButtonCircle" Stroke="Black" StrokeThickness="0" Fill="AliceBlue" Stretch="Uniform">
<Ellipse.Width>
<Binding ElementName="StatusButtonCircle" Path="ActualHeight"/>
</Ellipse.Width>
</Ellipse>
<Ellipse x:Name="StatusButtonCircleHighlight" Margin="4" Stroke="Black" StrokeThickness="2" Stretch="Uniform">
<Ellipse.Width>
<Binding ElementName="StatusButtonCircleHighlight" Path="ActualHeight"/>
</Ellipse.Width>
</Ellipse>
<ContentPresenter HorizontalAlignment="Center"
VerticalAlignment="Center">
<ContentPresenter.Resources>
<Style TargetType="TextBlock" BasedOn="{x:Null}"/>
<!-- Assigned Blank style here therefore it will not search for any further style-->
</ContentPresenter.Resources>
</ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
You can do it with the BasedOn. I show you an example.
<Window.Resources>
<Style TargetType="ToggleButton" BasedOn="{StaticResource DefToggleButton}">
<Setter Property="FontWeight" Value="Bold"/>
<Setter Property="Content" Value="Some Cool Stuff"/>
<Style.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Content" Value="More Stuff"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
Here in my resources I have DefToggleButton, now in my xaml file I can set up any Property according to my need (which in this case is the FontWeight and Content Property).
I think if you remove the Template from your Style, then you can do what you want to do, like this:
<Window.Resources>
<Style TargetType="Button" x:Key="stBtn>
<Setter Property="Background" Value="Blue" />
<Setter Property="Foreground" Value="White" />
<Setter Property="FontFamily" Value="Segoe UI Semibold" />
</Style>
</Window.Resources>
The Template that you have says, that all Buttons should be shown as a Border with a ContentPresenter inside, which is not what you have asked.
Without the Template, you can define your Buttons like this:
<Button Content="Hi!" Style="{StaticResource stBtn}" Foreground="Red" >
Like this, you have a Blue Button with Red Foreground.
=================
Edit
So what if you define a Template, and use it in you style, like this?
Then, by TemplateBinding you can define that the Foreground and teh Content come later, when the Button is actually defined.
<Window.Resources>
<ControlTemplate x:Key="ctBtn" TargetType="{x:Type Button}">
<Label Background="Green" Content="{TemplateBinding Content}" Foreground="{TemplateBinding Foreground}"/>
</ControlTemplate>
<Style x:Key="stBtn2" TargetType="{x:Type Button}">
<Setter Property="Template"
Value="{StaticResource ctBtn}" />
</Style>
<Window.Resources>
Then by defining the Button:
<Button Content="Hi!" Style="{StaticResource stBtn2}" Foreground="Red" >
===============
Edit2
So the general idea is that you can define a TemplateBinding for the properties of the elements in your template. So for example,you have an Ellipse in your template:
<Ellipse Fill="{TemplateBinding BorderBrush}" />
This defines that the Fill property of your Ellipse comes from the BorderBrush of your Button (Assuming that the template is targeting a Button)
Accordingly, you can put a Label in your Template, and set a TemplateBinding for its Forground and FontWeight property.
<Label Foreground="{TemplateBinding Foreground}" />
First, for this issue to be reproduced, Styles need to be set within a ResourceDictionary which is then added to Application.Resources (precisellyTextBlock global style). Setting Styles within for example Window.Resources will not reproduce the issue.
Global TextBlock Style is applied to the TextBlock created by ConentPresenter
As noticed in the question, the issue is that the global (keyless) Style for TextBlock is applied to the TextBlock created by ContentPresenter when it concludes the content to display is a string. For some reason this doesn't happen when that Style is defined within Window.Resources. As it turns out, there is more to this than just "controls are looking for their styles within their parent's resources".
ControlTemplate is a boundary for elements not deriving from Control class
For TextBlock (which doesn't derive from Control class, but from UIElement) within ControlTemplate, it means that wpf will not look for it's implicit Style beyond it's templated parent. So it won't look for implicit Style within it's parent's resources, it will apply application level implicit Style found within Application.Resources.
This is by design (hardcoded into FrameworkElement if you will), and the reason is exactly to prevent issues like this one. Let's say you're creating a specific Button design (as you are) and you want all buttons in your application to use that design, even buttons within other ControlTemplates. Well, they can, as Button does derive from Control. On the other hand, you don't want all controls that use TextBlock to render text, to apply the implicit TextBlock Style. You will hit the same issue with ComboBox, Label... as they all use TextBlock, not just Button.
So the conclusion is: do not define global Style for elements which don't derive from Control class within Application.Resources, unless you are 100% sure that is what you want (move it to Window.Resources for example). Or, to quote a comment I found in source code for MahApps.Metro UI library: "never ever make a default Style for TextBlock in App.xaml!!!". You could use some solution to style the TextBlock within your Button's ControlTemplate, but then you'll have to do it for Label, ComboBox, etc... So, just don't.
I have a Button Style with a Template containing a ContentPresenter, in which I am attempting to bind the Fill of a Path to the Foreground of a button:
<!-- This is inside the template of a button style -->
<ContentPresenter>
<ContentPresenter.Resources>
<Style TargetType="{x:Type Path}">
<Setter Property="Fill" Value="{Binding Path=Foreground, RelativeSource={RelativeSource AncestorType=Button}}"/>
</Style>
</ContentPresenter.Resources>
</ContentPresenter>
I also have a Path with no Fill set, that I can reference in the button as the content, like so:
<Button Style="{DynamicResource MyButtonStyle}" Content="{DynamicResource PathIcon}" Foreground="Blue"/>
I would expect the Path inside the button to be blue, but it isn't... it doesn't grab the foreground from the button.
How can I get the Path to bind to the color of the button?
Thank you!
P.S.:
If I put a hardcoded color in the Value (i.e. Value="Red"), the Path inside the button is red... so I know that works...
<ContentPresenter>
<ContentPresenter.Resources>
<Style TargetType="{x:Type Path}">
<Setter Property="Fill" Value="Red"/>
</Style>
</ContentPresenter.Resources>
</ContentPresenter>
Edit:
Here is the complete Style and ControlTemplate:
<Style x:Key="Button_Style" TargetType="{x:Type Button}">
<Setter Property="Foreground" Value="{StaticResource White_Brush}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid x:Name="grid" Background="Transparent">
<ContentPresenter>
<ContentPresenter.Resources>
<Style TargetType="{x:Type Path}">
<Setter Property="Fill" Value="{Binding Path=Foreground, RelativeSource={RelativeSource AncestorType=Button}}"/>
</Style>
</ContentPresenter.Resources>
</ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<!-- Should affect Text as well as Paths in the Content property of the button! -->
<Setter Property="Foreground" Value="{StaticResource Black_Brush}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Okay, let's order:
it doesn't grab the foreground from the button.
In styles this construction:
RelativeSource={RelativeSource AncestorType=Button}
will not work, because the Style is just the collection of setters, he does not know about control, are there, specifically about the content of the visual tree. Because RelativeSource should refer to the items above in the visual tree. For this purpose, usually using DataTemplate or ControlTemplate.
If I put a hardcoded color in the Value (i.e. Value="Red")
Yes, in this case, will be working, and always better to create the design of the form:
<SolidColorBrush x:Key="MyButtonColor" Color="Blue" />
And use it for control, like Button:
<Button Background="{StaticResource MyButtonColor}" ... />
and in Style or elsewhere:
<Setter Property="Fill" Value="{StaticResource MyButtonColor}" />
That is, it is better not to depend on the element parameters (background color, etc.) located in a visual tree, because it can:
May move to another panel (Grid, StackPanel) or UserControl
May leave from the project
And brushes in the as resources will always be in one place, changing them in this place, all the elements of their pick up. Also colors can be stored in a special data model that does not depend on the specific technical implementations (resources, variables) in which the data can come from an external source, such as the project/config settings.
If possible, it is better to avoid the use of dynamic resources due to unnecessary use of system perfomance (and in some cases memory leaks), in your cases they are not needed.
Dynamic resources are usually explicitly defined for SolidColorBrush and another species brushes, because by default they are frozen, and they not recommended changed because of the above mentioned reasons (memory leaks). More information can be found here:
Freezable Objects Overview on MSDN
Edit
As I understand it, you want to make universal Style for Button to make the contents of Path or Text (in the case of simultaneous use will be easier). As I have already mentioned above, RelativeSource should be around ControlTemplate, therefore, the Path will be in the Grid with the ContentPresenter.
To style knew, which is provided for the text or for the path, to the Tag (optional property) indicates two properties: OnlyText or OnlyPath.
To set the data for the Path, I've created a attached dependency property, and prescribed it in the ControlTemplate.
Below is a complete example:
XAML
<Window x:Class="ButtonPathHelp.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:ButtonPathHelp"
xmlns:sys="clr-namespace:System;assembly=mscorlib"
WindowStartupLocation="CenterScreen"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<SolidColorBrush x:Key="Green_Brush" Color="Green" />
<SolidColorBrush x:Key="Black_Brush" Color="Black" />
<Style x:Key="Button_Style" TargetType="{x:Type Button}">
<Setter Property="Foreground" Value="{StaticResource Green_Brush}" />
<Setter Property="HorizontalAlignment" Value="Center" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid x:Name="grid">
<ContentPresenter x:Name="MyContent"
Content="{TemplateBinding Content}"
HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
VerticalAlignment="{TemplateBinding VerticalAlignment}" />
<Path x:Name="MyPath"
SnapsToDevicePixels="True"
Width="20"
Height="18"
Stretch="Fill"
Fill="{Binding Path=Foreground, RelativeSource={RelativeSource AncestorType={x:Type Button}}}"
Data="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(local:MyDependencyClass.DataForPath)}" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Foreground" Value="{StaticResource Black_Brush}"/>
</Trigger>
<Trigger Property="Tag" Value="OnlyText">
<Setter TargetName="MyPath" Property="Visibility" Value="Collapsed" />
<Setter TargetName="MyContent" Property="Visibility" Value="Visible" />
</Trigger>
<Trigger Property="Tag" Value="OnlyPath">
<Setter TargetName="MyPath" Property="Visibility" Value="Visible" />
<Setter TargetName="MyContent" Property="Visibility" Value="Collapsed" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<WrapPanel>
<WrapPanel.Resources>
<sys:String x:Key="Save">
F1 M 20.5833,20.5833L 55.4167,20.5833L 55.4167,55.4167L 45.9167,55.4167L 45.9167,44.3333L 30.0833,44.3333L 30.0833,
55.4167L 20.5833,55.4167L 20.5833,20.5833 Z M 33.25,55.4167L 33.25,50.6667L 39.5833,50.6667L 39.5833,55.4167L 33.25,
55.4167 Z M 26.9167,23.75L 26.9167,33.25L 49.0833,33.25L 49.0833,23.75L 26.9167,23.75 Z
</sys:String>
<sys:String x:Key="Search">
F1 M 23.4454,49.2637L 31.7739,41.1598C 30.6986,39.2983 30.4792,37.1377 30.4792,34.8333C 30.4792,27.8377 35.7544,
22.1667 42.75,22.1667C 49.7456,22.1667 55.4167,27.8377 55.4167,34.8333C 55.4167,41.8289 49.7456,47.1042 42.75,
47.1042C 40.5639,47.1042 38.5072,46.9462 36.7125,45.9713L 28.3196,54.1379C 27.0829,55.3746 24.6821,55.3746 23.4454,
54.1379C 22.2088,52.9013 22.2088,50.5004 23.4454,49.2637 Z M 42.75,26.9167C 38.3777,26.9167 34.8333,30.4611 34.8333,
34.8333C 34.8333,39.2056 38.3777,42.75 42.75,42.75C 47.1222,42.75 50.6667,39.2056 50.6667,34.8333C 50.6667,
30.4611 47.1222,26.9167 42.75,26.9167 Z
</sys:String>
</WrapPanel.Resources>
<Button Name="SaveButton"
Style="{StaticResource Button_Style}"
Tag="OnlyPath"
local:MyDependencyClass.DataForPath="{StaticResource Save}"
Margin="10" />
<Button Name="JustText"
Style="{StaticResource Button_Style}"
Tag="OnlyText"
Content="Just Text"
Margin="10" />
<Button Name="SearchButton"
Style="{StaticResource Button_Style}"
Tag="OnlyPath"
local:MyDependencyClass.DataForPath="{StaticResource Search}"
Margin="10" />
</WrapPanel>
</Window>
Code behind
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
}
public class MyDependencyClass : DependencyObject
{
#region IsCheckedOnDataProperty
public static readonly DependencyProperty DataForPathProperty;
public static void SetDataForPath(DependencyObject DepObject, string value)
{
DepObject.SetValue(DataForPathProperty, value);
}
public static string GetDataForPath(DependencyObject DepObject)
{
return (string)DepObject.GetValue(DataForPathProperty);
}
#endregion
static MyDependencyClass()
{
PropertyMetadata MyPropertyMetadata = new PropertyMetadata(String.Empty);
DataForPathProperty = DependencyProperty.RegisterAttached("DataForPath",
typeof(string),
typeof(MyDependencyClass),
MyPropertyMetadata);
}
}
Note: In the Style I have not used TemplateBinding for attached property, because TemplateBinding doesn’t work outside a template or outside its VisualTree property, so you can’t even use TemplateBinding inside a template’s trigger. Therefore, we must use the construction {RelativeSource TemplatedParent} and a Path equal to the dependency property whose value you want to retrieve.
Output
To download the entire example please follow this link.
I stumbled across simillar problem but was wondering how to get to the 'Foreground Colour' of the Button in its DISABLED state (to have correct colour of my drawing). Here is a finally simple sollution. No templates, No styles, no code, nothing at all. Just the right relative binding :-) :
<StackPanel Orientation="Horizontal">
<Button Height="22" IsEnabled="False">
<Polygon Points="4,0 4,5 5,5 2.5,10 0,5 1,5 1,0 "
Fill="{Binding (TextElement.Foreground), RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContentPresenter}}}">
<Polygon.LayoutTransform>
<RotateTransform Angle="90"></RotateTransform>
</Polygon.LayoutTransform>
</Polygon>
</Button>
<Button Height="22" IsEnabled="True">
<Polygon Points="4,0 4,5 5,5 2.5,10 0,5 1,5 1,0 "
Fill="{Binding (TextElement.Foreground), RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContentPresenter}}}">
<Polygon.LayoutTransform>
<RotateTransform Angle="180"></RotateTransform>
</Polygon.LayoutTransform>
</Polygon>
</Button>
</StackPanel>
Sorry if this is a dense question, but I'm looking to see if there is a way to have a style resource of Canvas in App.xaml and also have children on that Canvas and just refer to it in the Style of another canvas. The resource I envision would be something like:
<Style x:Key="Background1" TargetType="Canvas">
<Setter Property="Width" Value="500"/>
<Setter Property="Height" Value="600" />
<Setter Property="Background" Value="Red"/>
<Setter Property="Children">
<Setter.Value>
<Rectangle Canvas.Top="20" Canvas.Left="20" Width="100" Height="100" Fill="Yellow"></Rectangle>
</Setter.Value>
</Setter>
</Style>
And then calling it would be as simple as:
<Canvas Style="{StaticResource Background1}" x:Name="CanvasRoot" >
<Rectangle x:Name="PageRectangle" Canvas.Left="114" Canvas.Top="84" Height="378" Width="210" Stroke="#92D050" Fill="#C0504D" />
</Canvas>
Any thoughts on if something like this can be done. What I've done doesn't work because there is no "Children" property on Canvas.
So you want to add a child to a Canvas via a Style? I'm afraid this is simply not possible. Styles allows you to set the values of an elements dependency properties, such as Height, Background, Stroke etc ... You can also use them to set attached properties. However, the Children property you are trying to set is not a dependency property, it is the collection of children elements that describe the children of your canvas in the visual tree.
The only way to add new elements t the visual tree using styles is to add them to some controls template. Unfortunately you canot template panels (Canvas, Grid, StackPanel). You could use a ContentControl and add your rectangle as part of its template.
A ContentControl is a lookless container of a single child. See the template described here:
http://msdn.microsoft.com/en-us/library/dd334411%28VS.95%29.aspx
Here it is, templates to add a rectangle. I am not sure what layout you are trying to achieve, but it should give you the general idea
<Style TargetType="ContentControl" x:Key="myContentControl">
<Setter Property="Foreground" Value="#FF000000"/>
<Setter Property="HorizontalContentAlignment" Value="Left"/>
<Setter Property="VerticalContentAlignment" Value="Top"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ContentControl">
<Canvas>
<Rectangle Canvas.Top="20" Canvas.Left="20" Width="100" Height="100" Fill="Yellow"></Rectangle>
<ContentPresenter
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
Cursor="{TemplateBinding Cursor}"
Margin="{TemplateBinding Padding}"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Canvas>
</ControlTemplate>
</Setter.Value>
</Setter>
<ContentControl Style={StaticResource myContentControl}>
<Canvas x:Name="CanvasRoot" >
<Rectangle x:Name="PageRectangle" Canvas.Left="114" Canvas.Top="84" Height="378" Width="210" Stroke="#92D050" Fill="#C0504D" />
</Canvas>
</ContentControl>
I'm currently trying to create a ControlTemplate for the Button class in WPF, replacing the usual visual tree with something that makes the button look similar to the little (X) close icon on Google Chrome's tabs. I decided to use a Path object in XAML to achieve the effect. Using a property trigger, the control responds to a change in the IsMouseOver property by setting the icon's red background.
Here's the XAML from a test app:
<Window x:Class="Widgets.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">
<Window.Resources>
<Style x:Key="borderStyle" TargetType="Border">
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background">
<Setter.Value>
<SolidColorBrush Color="#CC0000"/>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
<ControlTemplate x:Key="closeButtonTemplate" TargetType="Button">
<Border Width="12" Height="12" CornerRadius="6"
BorderBrush="#AAAAAA" Background="Transparent"
Style="{StaticResource borderStyle}"
ToolTip="Close">
<Viewbox Margin="2.75">
<Path Data="M 0,0 L 10,10 M 0,10 L 10,0" Stroke="{Binding BorderBrush, RelativeSource={RelativeSource FindAncestor, AncestorType=Border, AncestorLevel=1}}" StrokeThickness="1.8"/>
</Viewbox>
</Border>
</ControlTemplate>
</Window.Resources>
<Grid Background="White">
<Button Template="{StaticResource closeButtonTemplate}"/>
</Grid>
</Window>
Note that the circular background is always there - it's just transparent when the mouse isn't over it.
The problem with this is that the trigger just isn't working. Nothing changes in the button's appearance. However, if I remove the Background="Transparent" value from the Border object in the ControlTemplate, the trigger does work (albeit only when over the 'X').
I really can't explain this. Setters for any other properties placed in the borderStyle resource work fine, but the Background setter fails as soon as the default background is specified in the ControlTemplate.
Any ideas why it's happening and how I can fix it? I know I could easily replace this code with, for example, a .PNG-based image, but I want to understand why the current implementation isn't working.
Thanks! :)
Try moving the explict "Background" assignment from inside the Border declaration to the Style itself:
<Style x:Key="borderStyle" TargetType="Border">
<Setter Property="Background" Value="Transparent" />
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background">
<Setter.Value>
<SolidColorBrush Color="#CC0000"/>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
...
<Border Width="12" Height="12" CornerRadius="6"
BorderBrush="#AAAAAA"
Style="{StaticResource borderStyle}"
ToolTip="Close">
Styles can't override a property that has been explicitly set. You need to set the value in the style.
I think your problem is that the Border does not 'catch' the mouse events when it is transparant.
To verify - try changing the background to #01FFFFFF instead of Transparent.