WPF: Set style on immediate children only - wpf

In my application I have a tab control which has several tab items.
The problem is that I want to apply a style to these tab items, but to no other (nested) tab items.
I have tried setting the following style on the tab control, but this also effects all children:
<Style x:Key="tabControlStyle" TargetType="{x:Type TabControl}">
<Setter Property="TabItem.Template" Value="{StaticResource tabItemTemplate}" />
</Style>
By using the code above I get the following error: 'TabItem' ControlTemplate TargetType does not match templated type 'TabControl', as TabItem and TabControl have the same DependencyProperty "Template", and the code tries to set the TabItemTemplate as TabControl- Template.
Can anybody help me?

Use the ItemContainerStyle property to apply a style to the items of an items control:
<Style x:Key="tabControlStyle" TargetType="{x:Type TabControl}">
<Setter Property="ItemContainerStyle" Value="{x:StaticResource tabItemStyle}" />
</Style>

Related

Override item Style Template with a DataTemplateSelector

I've got a Style on ListViewItem that sets the Theme property
<Style x:Key="{x:Type ListViewItem}" TargetType="{x:Type ListViewItem}">
<Setter Property="Template" Value="{StaticResource ListViewItemTemplate}"/>
</Style>
However, in one of the cases where I'm using a ListView I want to use a DataTemplateSelector to determine which Template to use
<Style x:Key="MyListStyle" TargetType="{x:Type ListView}" BasedOn="{StaticResource {x:Type ListView}}">
<Setter Property="ItemTemplateSelector" Value="{StaticResource MyItemTemplateSelector}"/>
</Style>
It's applied like this
<ListView Style="{StaticResource MyListStyle}/>
However, it would appear that the Style on the item takes over and that style is applied to all the items in the ListView. I found this question which had a similar problem, however, the solution simply doesn't use the Template on the Item style at all. I need to keep that.
I've played around with the ContentTemplateSelector by restyling the ListViewItems in that ListView
<Style x:Key="MyItemStyle" BasedOn="{StaticResource {x:Type ListViewItem}}" TargetType="{x:Type ListViewItem}">
<Setter Property="ContentTemplateSelector" Value="{StaticResource MyItemTemplateSelector}"/>
</Style>
However, the Template on the other style is used instead. If I try nulling the Template then nothing shows up at all!
<Setter Property="Template" Value="{x:Null}"/
Is there a way that I can replace the Template on the ListViewItems for a given ListView while keeping the rest of my Style?
I was unable to override the Template set on the ListViewItem in the ListView Style.
To get around this I replaced the Template on the ListViewItem with another ItemTemplateSelector in my base ListView Style. This selector always returns my original Template. In my ListView child Style the new ItemTemplateSelector is used.

Stop child from inheriting parent Style in TabControls

In my WPF application i have a TabControl that i am binding to a style i created:
On my View:
<TabControl Grid.Row="6" Style="{DynamicResource SideBarTabControl}">
On a separate ResourceDictionary:
<Style x:Key="SideBarTabControl" TargetType="{x:Type TabControl}" BasedOn="{StaticResource {x:Type TabControl}}" >
<Setter Property="FontSize" Value="{DynamicResource TitleFontSize}"/>
</Style>
So far so good, things work as expected. The problem is that now all the children of this TabControl, such as a ListView inside a TabItem, is also getting the same FontSize as the TabControl, instead of the default.
I thought that by specifying TargetType="{x:Type TabControl}" i would stop the style from being applied to children of different types. What i'm looking for is to actually stop it from affecting EVERYTHING BUT the component that explicitly inherited the style. So how can this be done? I think i am missing something simple...
If i override the font size in my ListView it works, but this means i have to do it for every child, which might become very cumbersome.
I have read this and other questions but i can't find the answer i'm looking for:
Is it possible to set a style in XAML that selectively affects controls?
This is working for me. The part that's doing the work is TabControl.ItemContainerStyle. It applies a font size only to the header content.
<TabControl>
<TabControl.ItemContainerStyle>
<Style
TargetType="TabItem"
BasedOn="{StaticResource {x:Type TabItem}}"
>
<Setter Property="HeaderTemplate">
<Setter.Value>
<DataTemplate>
<ContentControl
TextElement.FontSize="20"
Content="{Binding Header, RelativeSource={RelativeSource AncestorType=TabItem}}"
/>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
</TabControl.ItemContainerStyle>
<TabItem Header="Foo">
<Label Content="Bar" />
</TabItem>
<TabItem Header="Baz">
<Label Content="Bar" />
</TabItem>
</TabControl>
You cannot stop it, it's not the style causing this unwanted trickle-down effect you want rid of; it's just how WPF controls work.
What you will have to do to stop this is write another style for your tab items to intercept the one being inherited from the TabControl.
I suggest writing this style inside your existing TabControl style, inside the Style.Resources tag like so:
<Style x:Key="SideBarTabControl" TargetType="{x:Type TabControl}" BasedOn="{StaticResource {x:Type TabControl}}" >
<Style.Resources>
<Style TargetType="{x:Type TabItem}">
<Setter Property="FontSize" Value="9001"/>
<!-- Any other setters you want for TabItems -->
</Style>
</Style.Resources>
<Setter Property="FontSize" Value="{DynamicResource TitleFontSize}"/>
</Style>
By making a style inside your other style's resources, it will be carried with it, and by not specifying any x:Key for the TabItem style - it will apply it to any TabItem not ordered to have a specific style, becoming the default style for any TabItem you make inside the TabControl now.

WPF Stackpanel spacing between custom controls

how is it possible to get a space between some custom controls inside a stackpanel? I did it right before with a Textbox, Button, and so on, but i cannot do it with a custom control.
That's the code i've got so far
<Grid>
<StackPanel x:Name="spTasks" CanVerticallyScroll="True">
<StackPanel.Resources>
<Style TargetType="local:SmartTaskOverview">
<Setter Property="Margin" Value="50,50,50,50" />
</Style>
</StackPanel.Resources>
</StackPanel>
</Grid>
Thanks for your help
FrameworkElements and their sub-classes don't just look for a resource using the controls type, they use the value of DefaultStyleKey. It's common practice for most sub-classes of Control (and some other FrameworkElements) to override the default value of this dependency property in the static constructor to be the type of the control, but sub-classes of UserControl usually don't bother.
static Foo()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(Foo), new FrameworkPropertyMetadata(typeof(Foor));
}
If you didn't do this in your SmartTaskOverview then it will be looking for its default style using typeof(UserControl) as the resource key and not typeof(SmartTaskOverview).
Note: The UserControl will require a control template to show its children, this is normally provided by the default style for UserControl but by changing the key it will find your default style instead. To resolve this, just base your style on the UserControl style.
<Style TargetType="local:SmartTaskOverview" BasedOn="{StaticResource {x:Type UserControl}}">
<Setter Property="Margin" Value="50,50,50,50" />
</Style>
Alternatively you could provide a simple template yourself.
<Style TargetType="local:SmartTaskOverview">
<Setter Property="Margin" Value="50,50,50,50" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:SmartTaskOverview}">
<ContentPresenter />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Images direction changed because FlowDirection is set to RightToLeft

I have a WPF UserControl in which I've defined FlowDirection="RightToLeft"
I've noticed that the direction of all button images in the toolbar has changed because of that.
How can I avoid that without setting FlowDirection="LeftToRight" for each button ?
You can declare default Style in your resource for button so that it gets applied to all button by default in your UserControl. This way you don't have to go each button and set its property manually.
<UserControl.Resources>
<Style TargetType="Button">
<Setter Property="FlowDirection" Value="LeftToRight"/>
</Style>
</UserControl.Resources>
It won't work for button since buttons in toolbar apply style identified by ToolBar.ButtonStyleKey. So add you need to have two styles and simply set second style to be based on first button. This is how you will do that:
<UserControl.Resources>
<Style TargetType="Button">
<Setter Property="FlowDirection" Value="LeftToRight"/>
</Style>
<Style x:Key="{x:Static ToolBar.ButtonStyleKey}" TargetType="Button"
BasedOn="{StaticResource {x:Type Button}}"/>
</UserControl.Resources>

WPF global font size

I'm creating a WPF app and I would like to know the best way to be able to change the font size for every element in the ui. Do I create a resource dictionary and set Styles to set the font size for all the controls I use?
What is the best practice?
I'd do it this way:
<Window.Resources>
<Style TargetType="{x:Type Control}" x:Key="baseStyle">
<Setter Property="FontSize" Value="100" />
</Style>
<Style TargetType="{x:Type Button}" BasedOn="{StaticResource baseStyle}"></Style>
<Style TargetType="{x:Type Label}" BasedOn="{StaticResource baseStyle}"></Style>
<Style TargetType="{x:Type TextBox}" BasedOn="{StaticResource baseStyle}"></Style>
<Style TargetType="{x:Type ListView}" BasedOn="{StaticResource baseStyle}"></Style>
<!-- ComboBox, RadioButton, CheckBox, etc... -->
</Window.Resources>
That way, if I want to change ALL the controls, I'd just have to change the "baseStyle" style, the rest would just inherit from it. (That's what BasedOn property those, you can also extend the base style if you create other setters inside of the inherited style)
FontSizeProperty is inherited from Parent Control. So you just need to change FontSize of your main window.
If you don't need dynamic behaviour this should work:
Add a style for Window to your ResourceDictionary
<Style TargetType="{x:Type Window}">
<Setter Property="FontSize" Value="15" />
</Style>
Apply the style to your main form (will not be applied implicit because its a derived type)
Style = (Style)FindResource(typeof (Window));
<Window> has a property FontSize.
So you can set desired fontsize in element if you want to change the fontsize in all the elements within that window.
<Window FontSize="12">
</Window>
Another option is to define the FontFamily and FontSize as resources.
<FontFamily x:Key="BaseFontFamily">Calibri</FontFamily>
<sys:Double x:Key="BaseFontSize">12</sys:Double>
That way you can use them in your setters.
Application.Current.MainWindow.FontSize = _appBodyFontSize;
This way you can change the Font Size at run time also.
TextElement.FontSize is an inherit property, which means you can simply set the font size at root element, and all the children elements will use that size (as long as you don't change them manually)
For any styles in WPF, you should have a separate resource dictionary that contains the styles for your app.
If you want to have a single Font Size that's reused throughout the app then just create a style for that font size. You can either give it a unique name/key to use explicitly or you can set a targetType that will transcend throughout the app.
Explicit Key:
<Style
x:Key="MyFontSize"
TargetType="TextBlock">
<Setter
Property="FontSize"
Value="10" />
</Style>
<Control
Style="{StaticResource MyFontSize}" />
*Note this style can be used with controls that have contentPresenters
For all textblocks in the app:
<Style
TargetType="TextBlock">
<Setter
Property="FontSize"
Value="10" />
</Style>
<TextBlock
Text="This text will be size 10" />
If you need to programmatically change global FontSize, not statically (XAML), to be applied once for all your windows, you can do:
TextElement.FontSizeProperty.OverrideMetadata(
typeof(TextElement),
new FrameworkPropertyMetadata(16.0));
TextBlock.FontSizeProperty.OverrideMetadata(
typeof(TextBlock),
new FrameworkPropertyMetadata(16.0));
This values are applied to any TextBlock, Labels and almost any text in any windows, whereas it has not a explicit FontSize defined. But this does not affect for TextBox, you have to write a similar code for it or any other special controls.
To dynamically change the font size globally with ctrl-mousewheel:
XAML:
<Window Name="MainWindow" ... PreviewMouseWheel="MainWindow_PreviewMouseWheel">
code behind:
private void MainWindow_PreviewMouseWheel(object sender, MouseWheelEventArgs e)
{
if ((Keyboard.Modifiers & ModifierKeys.Control) != 0)
{
if (e.Delta > 0)
++mainCtrl.FontSize;
if (e.Delta < 0 && mainCtrl.FontSize > 1)
--mainCtrl.FontSize;
}
}
Using Resources in XAML is the way to go. Although there are many great answers to this question, I would like to add my two cents to the SCOPE of the Resource.
For Global accessibility in all of the Windows and User Controls of the Project, you can have your resource in the App.xaml file
<Application.Resources>
<Style TargetType="{x:Type Control}" x:Key="GlobalFontSize">
<Setter Property="FontSize" Value="28"/>
</Style>
</Application.Resources>
For accessibility at a Window level, you can have your resource in your xaml file for Window
<Window.Resources>
<Style TargetType="{x:Type Control}" x:Key="GlobalFontSize">
<Setter Property="FontSize" Value="28"/>
</Style>
</Window.Resources>
You could even have it at a Control level, for example
<DockPanel.Resources>
<Style TargetType="{x:Type Control}" x:Key="GlobalFontSize">
<Setter Property="FontSize" Value="28"/>
</Style>
</DockPanel.Resources>
Let's have some BLACK MAGIC things:
Add a double resource into your Application resource
<Application.Resources>
<sys:Double xmlns:sys="clr-namespace:System;assembly=mscorlib" x:Key="GlobalFontSize">12</sys:Double>
</Application.Resources>
Add a static property in your App class
public static double GlobalFontSize
{
get => (double)Current.Resources["GlobalFontSize"];
set => Current.Resources["GlobalFontSize"] = value;
}
Use this resource any where you want by DynamicResource
FontSize="{DynamicResource GlobalFontSize}"
Access property App.GlobalFontSize in any way to change value, binding is okay!
App.GlobalFontSize = 20;
//Or
{Binding Path=(local:App.GlobalFontSize)}

Resources