Setter.Value Property

XAML Values

• objectValue
  An object element that specifies the value of the property being set.

• attributeValue
  A string that specifies the attribute value of the property being set. The format and interpretation of the string provided for the attribute value depends on the property being set.

• extensionUsage
  One of several possible extension mechanisms that specify the property value to be obtained from an existing value. The most common of these is StaticResource.

• Whether to use attribute syntax or property element syntax depends both on the property type of the property being set, as well as whether you choose to use extension mechanisms such as referencing existing resources. For example, property element syntax might be required if you want the style to define a new ImageBrush as the value for a property that takes a Brush property type, but attribute syntax could be used if you chose a SolidColorBrush instead, or referenced an existing ImageBrush with a StaticResource usage.

• Generally, objectValue is a single object element, but multiple object elements are technically possible in the usage if you are setting a dependency property that takes an implicit collection type.

Property Value

Type: System.Object
The value to apply to the property that is specified by the Setter.

<StackPanel>
  <StackPanel.Resources>
    <!--Create a Style for a TextBlock to specify that the
              Foreground equals Navy, FontSize equals 14, and
              VerticalAlignment equals Botton.-->
    <Style TargetType="TextBlock" x:Key="TextBlockStyle">
      <Setter Property="Foreground" Value="Navy"/>
      <Setter Property="FontSize" Value="14"/>
      <Setter Property="VerticalAlignment" Value="Bottom"/>
    </Style>

    <!--Create a Style for a TextBlock that specifies that
              the Width is 200, Height is 20, Margin is 4,
              Background is LightBlue, and FontSize is 14.-->
    <Style TargetType="TextBox" x:Key="TextBoxStyle">
      <Setter Property="Width" Value="200"/>
      <Setter Property="Height" Value="30"/>
      <Setter Property="Margin" Value="4"/>
      <Setter Property="FontSize" Value="14"/>
      <Setter Property="Background">
        <Setter.Value>
          <LinearGradientBrush StartPoint="0,0.5" EndPoint="1,0.5">
            <GradientStop Color="White" Offset="0.0"/>
            <GradientStop Color="LightBlue" Offset="0.5"/>
            <GradientStop Color="Navy" Offset="1"/>
          </LinearGradientBrush>
        </Setter.Value>
      </Setter>
    </Style>
  </StackPanel.Resources>

  <!--Apply the TextBlockStyle and TextBoxStyle to each 
          TextBlock and TextBox, respectively.-->
  <StackPanel Orientation="Horizontal">
    <TextBlock Style="{StaticResource TextBlockStyle}">
              First Name:
          </TextBlock>
    <TextBox Style="{StaticResource TextBoxStyle}"/>
  </StackPanel>
  <StackPanel Orientation="Horizontal">
    <TextBlock Style="{StaticResource TextBlockStyle}">
              Last Name:
          </TextBlock>
    <TextBox Style="{StaticResource TextBoxStyle}"  
                   Margin="6,4,4,4"/>
  </StackPanel>
</StackPanel>

<UserControl x:Class="SL5DataBindingFeatures.StyleTestPage"
  xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml">

  <StackPanel x:Name="LayoutRoot">

    <StackPanel.Resources>
      <Style TargetType="TextBlock">
        <Setter Property="FontSize" Value="{Binding FontSize}"/>
      </Style>
    </StackPanel.Resources>

    <TextBlock Text="FontSize"/>
    <TextBox Text="{Binding FontSize, Mode=TwoWay}"
      TextChanged="TextBox_TextChanged"/>

  </StackPanel>

</UserControl>

Imports System.ComponentModel

Partial Public Class StyleTestPage
    Inherits UserControl

    Public Sub New()
        InitializeComponent()
        DataContext = New UserSettings() With {.FontSize = 35}
    End Sub

    Private Sub TextBox_TextChanged(sender As System.Object,
                                    e As TextChangedEventArgs)
        ' Update the data source whenever the text box value changes.
        CType(sender, TextBox) _
            .GetBindingExpression(TextBox.TextProperty).UpdateSource()
    End Sub
End Class

Public Class UserSettings
    Implements INotifyPropertyChanged

    Private _fontSize As Double
    Public Property FontSize As Double
        Get
            Return _fontSize
        End Get
        Set(value As Double)
            _fontSize = value
            RaiseEvent PropertyChanged(
                Me, New PropertyChangedEventArgs("FontSize"))
        End Set
    End Property

    Public Event PropertyChanged As PropertyChangedEventHandler _
        Implements INotifyPropertyChanged.PropertyChanged

End Class

using System;
using System.ComponentModel;
using System.Windows.Controls;

public partial class StyleTestPage : UserControl
{
    public StyleTestPage()
    {
        InitializeComponent();
        DataContext = new UserSettings() { FontSize = 35 };
    }

    private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
    {
        // Update the data source whenever the text box value changes.
        (sender as TextBox)
            .GetBindingExpression(TextBox.TextProperty).UpdateSource();
    }
}

public class UserSettings : INotifyPropertyChanged
{
    private Double _fontSize;
    public Double FontSize 
    {
        get { return _fontSize; }
        set 
        {
            _fontSize = value;
            PropertyChanged(this, new PropertyChangedEventArgs("FontSize"));   
        }
    }
    // Initialize to an empty delegate so that PropertyChanged is never null.
    public event PropertyChangedEventHandler PropertyChanged = delegate { };
}