WPF STYLE: Can't change background of button?

Question

I trying to change background of one button when another button clicked.

i can't do this if i providing style to button.

See my below code.

MainWindow.xaml

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <Style TargetType="Button" x:Key="TransparentButton">
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border  CornerRadius="2,2,2,2"  HorizontalAlignment="Center" x:Name="borderTemplate" Background="Transparent">
                            <ContentPresenter/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="true">
                                <Setter TargetName="borderTemplate"  Property="Border.BorderBrush" Value="Gray" />
                                <Setter TargetName="borderTemplate"  Property="Border.BorderThickness" Value="1" />
                            </Trigger>
                            <Trigger Property="IsPressed" Value="true">
                                <Setter TargetName="borderTemplate"  Property="Border.BorderBrush" Value="Lime" />
                            </Trigger>
                            <Trigger Property="IsFocused" Value="true">
                                <Setter TargetName="borderTemplate"  Property="Border.Background" Value="#FD7" />
                            </Trigger>

                            <Trigger Property="IsEnabled" Value="false">
                                <Setter TargetName="borderTemplate"  Property="Border.Background" Value="LightGray"></Setter>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Window.Resources>
    <Grid>
        <Button Content="Button" Style="{StaticResource TransparentButton}" Height="23" HorizontalAlignment="Left" Margin="20,25,0,0" Name="button1" VerticalAlignment="Top" Width="75" />
        <Button Content="Button" Height="23" HorizontalAlignment="Left" Margin="143,177,0,0" Name="button2" VerticalAlignment="Top" Width="75" Click="button2_Click" />
    </Grid>
</Window>

MainWindow.xaml.cs

 public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void button2_Click(object sender, RoutedEventArgs e)
        {
            //This doesn't work if i providing style to button  ==> Style="{StaticResource TransparentButton}"
            button1.Background = Brushes.Red;
        }
    }

Thanks.....

Answer 1

I already answered this in your other question

Your style re-writes the Button's ControlTemplate, so the Background color is no longer used

The Default button template looks like this:

<Button Background="SomeColor">
    <Button.Content>
</Button>

And you are overwritting the template to say

<Border>
    <Button.Content>
</Border>

Change your ControlTemplate to

<Border Background="{TemplateBinding Background}">
    <Button.Content>
</Border>

and it will work

Answer 2

Looks like a style which is defined in template ( Background="Transparent" ) always overrides a value you've provided from code behind. Try to remove it from XAML and define in constructor as default background of a button. Just to check. In general I would not suggest to do it in code behind, move such logic in XAML instead.

Answer 3

On this line:

<Border  CornerRadius="2,2,2,2"  HorizontalAlignment="Center" x:Name="borderTemplate" Background="Transparent">

You fix the Background of the button to transparent. It is no longer linked to the Background property of the button control so changing that property no longer propagates down to the style.

If you use a "TemplatedParent" binding it will allow you to reattach the link between the control and it's style - like this:

<Border  CornerRadius="2,2,2,2"  HorizontalAlignment="Center" x:Name="borderTemplate" Background="{Binding  RelativeSoure={RelativeSource TemplatedParent}, Path=Background}">

And then you can set the background of the button:

<Button Name="button1" Background="Transparent" ..... />