The method I've used in my applications is to create a class that implements INotifyPropertyChanged and contains regular CLR properties for the values I'd like to change at runtime, create an instance of that class in my resources file, and then bind my
various elements to it.
The problem with the static resource approach suggested by others is that the change in color will only be reflected once the view has been recreated since static resources are only bound once.
This is my ApplicationPreferences.cs file. Note that I'm handling some other cases in here as well such as providing a default value for design time and a runtime default value if the user doesn't have a previously saved value:
using System;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using Windows.Storage;
namespace MyApp.Services
{
public class ApplicationPreferences : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
public String AccentColor
{
get
{
if (Windows.ApplicationModel.DesignMode.DesignModeEnabled) { return "#9E0B0E"; }
var storedValue = ApplicationData.Current.LocalSettings.Values["AccentColor"] as string;
return string.IsNullOrWhiteSpace(storedValue) ? "#9E0B0E" : storedValue;
}
set
{
var storedValue = ApplicationData.Current.LocalSettings.Values["AccentColor"] as string;
if (value != storedValue)
{
ApplicationData.Current.LocalSettings.Values["AccentColor"] = value;
OnPropertyChanged();
}
}
}
}
}
Then inside my resources file I have:
<services:ApplicationPreferences x:Key="Preferences"/>
And I bind to it in my views like this:
<TextBlock FontFamily="Segoe UI" FontSize="20" Foreground="{Binding AccentColor, Source={StaticResource Preferences}}">
Now any time I change AccentColor, it's immediately reflected everywhere.
Dan Rigby -
http://danrigby.com
