Blue mouse over effect on button in Blend / WPF - wpf

Question

I just started getting used to WPF using Blend for Visual Studio. I created previous programs with the standart Windows Forms and now want to get to something more modern.
But I already encountered a main problem after like 5 Minutes.
I added a button with an background image with a transperancy. That worked like a charm, but the problem is that, when I run the application, the button always gets blue when the Mouse hovers it. I do not want this blue effect but can't find the option to disable it in Blend.
Hope someone can help me with this stupid question, Windows Forms was a little

Answer 1

What you're describing is the default state behavior for the button. You would have to create a custom template or style to change it. Example:
<Button Content="Button">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Black"/>
<Setter Property="Foreground" Value="White"/>
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
I am demonstrating two properties changes here: Background & Foreground. You may have as many as you want and change them to whatever value you wish. If you don't want any changes, simply remove Style.Triggers or a particular property within it.
Here's a demo for you, since you're new:
Here's the Resource Dictionary way:
Create a Resource Dictionary and add a style to it:
<Style x:Key="CustomButtonStyle" TargetType="Button">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Black"/>
<Setter Property="Foreground" Value="White"/>
</Trigger>
</Style.Triggers>
</Style>
Place this in your App.xaml or wherever you merge your resource dictionaries:
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="ButtonStyles.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
Then simply specify the style for your button:
Style="{StaticResource CustomButtonStyle}"