How can I change property control by code? - wpf-controls

Question

I defined a button by xamp look like:
<Window.Resources>
<Style x:Key="mybutton" TargetType="Button">
<Setter Property="Width" Value="200"/>
<Setter Property="Height" Value="200"/>
<Setter Property="HorizontalAlignment" Value="Left"/>
<Setter Property="VerticalAlignment" Value="Top"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Border BorderThickness="5" BorderBrush="#7A2D37" CornerRadius="5">
<Rectangle x:Name="myele">
<Rectangle.Fill>
<LinearGradientBrush StartPoint="0 0" EndPoint="1 1">
<GradientStop Color="White" Offset="0.1"></GradientStop>
<GradientStop Color="#28009B" Offset="1"></GradientStop>
</LinearGradientBrush>
</Rectangle.Fill>
</Rectangle>
</Border>
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"></ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<Button Margin="100" Style="{StaticResource mybutton}" Click="Button_Click"></Button>
</Grid>
And Button_click event:
private void Button_Click(object sender, RoutedEventArgs e)
{
Button btn = (Button)sender;
btn.BorderBrush = Brushes.Yellow;
btn.BorderThickness = new Thickness(30);
}
But when I click the button, the border did not change.
Could you give me your advance. Thank you verry much.

Answer 1

In the ControlTemplate, use {TemplateBinding ...} for BorderBrush and BorderThickness. And provide those default values via Setter. Then you can change them by code.
<Style x:Key="mybutton" TargetType="Button">
<Setter Property="Width" Value="200"/>
<Setter Property="Height" Value="200"/>
<Setter Property="HorizontalAlignment" Value="Left"/>
<Setter Property="VerticalAlignment" Value="Top"/>
<Setter Property="BorderBrush" Value="#7A2D37"/>
<Setter Property="BorderThickness" Value="5"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Border BorderThickness="{TemplateBinding BorderThickness}" BorderBrush="{TemplateBinding BorderBrush}" CornerRadius="5">
<Rectangle x:Name="myele">
<Rectangle.Fill>
<LinearGradientBrush StartPoint="0 0" EndPoint="1 1">
<GradientStop Color="White" Offset="0.1"></GradientStop>
<GradientStop Color="#28009B" Offset="1"></GradientStop>
</LinearGradientBrush>
</Rectangle.Fill>
</Rectangle>
</Border>
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"></ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>