How to change the header background of a GroupBox?

Question

How can I change the Background of the header of a GroupBox? I'm trying to do that with:

<GroupBox Grid.Row="0">
   <GroupBox.Header>
       <Setter Property="Background" //<- no backgroundproperty

there is no Background property

Answer 1

You can define a Border in the Header and set the Background of it to your desired color:

<GroupBox >
    <GroupBox.Header>
        <Border Background="Red">
            <Label Content="Hello"></Label>
        </Border>
    </GroupBox.Header>
</GroupBox>