In a WPF application (as of .NET 3.5) you can set the background color for a text block as follows:
<TextBlock ... Background="Red" ...> </TextBlock>Despite being correct Silverlight 2 doesn't like this XAML code. Trying to set it programmatically leads to an exception. Therefore a different solution is needed.
Here is what works in my case. I use a Canvas and place a Rectangle and a TextBlock inside of that Canvas. Unless you set the ZIndex use this order so that the TextBlock is in front of the Rectangle.
I use the Rectangle as the background for the TextBlock. When the TextBlock changes its size I update the size of the Rectangle accordingly. This solution is pretty simple in the end. First the XAML code:
Next the C# code-behind:
<UserControl x:Class="Foo.LabelWithBackground"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Width="200" Height="20">
<Canvas>
<Rectangle Name="_labelBackground" Width="20" Height="20"
Fill="LightSkyBlue"/></Rectangle>
<StackPanel>
<TextBlock Height="20" HorizontalAlignment="Left" Name="_label"
VerticalAlignment="Center" Padding="4,2,4,0"
Text="The Label Text" MinWidth="20"></TextBlock>
</StackPanel>
</Canvas>
</UserControl>
Of course you can use this UserControl in either a page (Silverlight) or in a window (WPF). In both cases you will get a label with background.
public partial class LabelWithBackground : UserControl {
public LabelWithBackground() {
InitializeComponent();
_label.SizeChanged += LabelSizeChanged;
}
void LabelSizeChanged(object sender, SizeChangedEventArgs e) {
_labelBackground.Width = _label.ActualWidth +
_label.Padding.Left + _label.Padding.Right;
}
}
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