windows phone 7: how to create an application theme?

Question

I would like to define a theme for my Windows Phone 7 application, to be applied at application launch regardless of the system theme set by the "Settings" phone menu. How can this be done?

I see on MSDN that Fill="{StaticResource PhoneAccentBrush}" allows the control using that brush to respond to system-wide theme changes. How can I do the same thing: to allow the control to get its brush, not from the system settings, but from my application settings?

And where should I put those settings, in order to have one style settings file that I can access from anywhere in my application?

Answer 1

There's no theme specific API in Silverlight. What you have is one or several resources dictionnary/ies that you can use to define a set of styles to be applied to your controls.

in Theme1.xaml file :

<Style x:Key="HeadingStyle" TargetType="{x:Type Label}">
     <Setter Property="Foreground" Value="Black"/>
</Style>

in Theme2.xaml file :

<Style x:Key="HeadingStyle" TargetType="{x:Type Label}">
  <Setter Property="Foreground" Value="Red"/>
</Style>

in App.xaml (the default theme or reference a default.xaml file):

<Application.Resources>
   <Style x:Key="HeadingStyle" TargetType="{x:Type Label}">
    <Setter Property="Foreground" Value="blue"/>
  </Style>
</Application.Resources>

To change the current "theme" :

Application.Current.Resources = Application.LoadComponent(new Uri("Theme2.xaml", UriKind.RelativeOrAbsolute));

I don't have right now the RTM tools installed so I can't test this code.